Selected Annotated 

Bibliography of the Uranium 

Geology of Igneous and 

Metamorphic Rocks 

in the United States

GEOLOGICAL SURVEY BULLETIN 1059-E

This compilation was done on behalf of 

the U. S. Atomic Energy Commission 

and is published with the permission of 

the Commission

Selected Annotated 

Bibliography of the Uranium 

' jeology of Igneous and

letamorphic Rocks

i the United States

V DIANE CURTIS

ELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

GEOLOGICAL SURVEY BULLETIN 10S9-E

This compilation was done on behalf of 

re U. S. Atomic Energy Commission 

vnd is published wttft the permissionj)f 

re Commission

NITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTO.N : 1958
UNITED STATES DEPARTMENT OF THE INTERIOR 

FRED A. SEATON, Secretary

GEOLOGICAL SURVEY 

Thomas B. Nolan, Director

For sale by the Superintendent of Documents, U. S. Government Printing Office 

Washington 25, D. C. - Price 55 cents (paper cover)
CONTENTS

	Pag* 

Abstract_____________.__________________________ 205

Explanation of the bibliography and index map._______________________ 205

Acknowledgments....--___________________________________________ 206

Annotated bibliography____________________________________ 207

Indexes_____________________________________________________ 257

Authors____________________________________________________ 257

Geographic areas____________________________________________ 259

Subjects..________________________________ 261

ILLUSTRATION

PLATE 2. Localities of igneous rocks in the United States.--------- In pocket

m

SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

SELECTED ANNOTATED BIBLIOGRAPHY OF THE URANIUM 

GEOLOGY OF IGNEOUS AND METAMORPHIG ROCKS IN 

THE UNITED STATES

By DIANE CURTIS

ABSTRACT

This bibliography consists of 117 references concerned with the uranium content 

and radioactivity of igneous and metamorphic rocks and minerals in the United 

States including Alaska and Hawaii. The annotations, arranged alphabetically 

by author, emphasize the geologic features of rocks and minerals for which uranium 

determinations have been made. An index map shows the location of igneous and 

metamorphic rocks and minerals that have been analyzed chemically for uranium.

Indexes are provided with entries listed according to author, geographic area, 

and subject.

EXPLANATION OF THE BIBLIOGRAPHY AND INDEX MAP

This bibliography is an annotated list of selected reports that 

pertain to the uranium content and (or) radioactivity of igneous and 

metamorphic rocks and minerals in the United States including 

Alaska and Hawaii, which were publicly available as of May 31, 1956. 

The annotations are listed alphabetically by author, and chronologically if there is more than one report by the same author. The 

references are numbered consecutively for indexing purposes. The 

statements on the stratigraphic classification and nomenclature 

are those of the various authors and do not necessarily follow usage 

of the U. S. Geological Survey. Material added in some annotations 

by the present author is enclosed in brackets.

A survey of the literature emphasized the paucity of published 

analytical data on this subject. Consequently, many reports that 

contain radioactivity data (particularly those with chemical analyses 

for uranium) are included in the bibliography, even though such 

reports may have little geologic information.

The uranium contents of igneous rocks as given in some of the 

reports were calculated by the authors of the reports from the radium 

content, on the assumption that equilibrium existed between the 

radioactive elements. The method of analysis used to determine the 

radium or uranium content has been indicated hi the annotation.

205
206 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Data inferred from radioactivity determinations have less quantitative 

significance than those derived from chemical analyses.

For consistency in this bibliography, analyses given in the reports 

as percent U3O8 have been converted to percent uranium, according 

to the following:

Percent U3O8 X0.85=percent U.

No papers specifically concerning the physical-chemical behavior 

of uranium during the crystallization of magmas were found in the 

current literature. However, a few general papers on the behavior 

of minor elements during crystallization were found, and the physicalchemical theory that they contain applies to uranium as well as to 

other minor elements. A selected few of these papers are included 

to provide some coverage of this important aspect of uranium in 

igneous rocks.

A number of abstracts from the foreign literature are included to 

provide a wide coverage of general concepts concerning the occurrence 

of uranium in igneous rocks. Papers relating to uranium in tuffaceous 

rocks are not included in this bibliography because they are in another 

bibliography of uranium in sandstone-type deposits (Melin, 1957, 

Selected annotated bibliography of the geology of sandstone-type 

uranium deposits in the United States: U. S. Geol. Survey Bull. 

1059-C).

The index map shows the location in the United States and Alaska 

of igneous rocks that have been analyzed chemically for uranium. 

The rocks are divided into granitic (including pegmatites), intermediate, extreme differentiates, and ultrabasic (including meteorites) types, 

and according to whether they are plutonic, volcanic, or metamorphic. 

The basis of classification of the different rock types is shown on 

plate 2.

The areas of igneous rocks in the United States, shown on plate 2, 

were compiled by E. Alien Merewether from the geologic map of the 

United States.

ACKNOWLEDGMENTS

The author appreciates the helpful suggestions and guidance given 

by George J. Neuerburg. Rosemary A. Robbins furnished a partial 

list of titles, and E. Alien Merewether assisted in the preparation of 

the index map.

The compilation was done by the U. S. Geological Survey on behalf 

of the Division of Raw Materials of the U. S. Atomic Energy Commission.
ANNOTATED BIBLIOGRAPHY

Adams, J. A. S., 1954, Uranium and thorium contents of volcanic rocks, 

in Faul, Henry, ed., Nuclear geology: New York, John Wiley & 

Sons Inc., p. 89-98.

On the basis of available analyses, the average uranium content of 

basic lavas is between 0.6 and 1.1 ppm. At Lassen [Lassen Volcanic 

National Park, Calif.] differentiation produced dacitic lavas with 4 times 

as much uranium as the most basic lava analyzed, and differentiation 

can be expected to produce acidic volcanic rocks with at least 6 times 

as much uranium as the average basic lavas. Obsidians with 15 ppm 

are known, and extreme differentiates may have even higher concentrations of uranium. Present data indicate that thorium is about 3 times 

more abundant than uranium in unweathered volcanic rocks and that 

this ratio probably holds constant during differentiation. Author's 

conclusions

Adams, J. A. S., 1955, The uranium geochemistry of Lassen Volcanic 

National Park, California: Geochim. et Cosmochim. Acta, v. 8, 

p. 74-85.

The uranium contents of samples of andesites, basalts, tuffs and dacites 

from Lassen Volcanic National Park, were determined fluorimetrically 

and ranged from 0.86 ppm in basalts to 3.6 ppm in a dacite. Values for 

the uranium content of similar samples determined fluorimetrically and 

by the direct fusion method (uranium recalculated from percent radium) 

are compared. The data indicate that the uranium and radium are in 

equilibrium.

There is a definite positive correlation between the amounts of uranium 

and potassium; the uranium content of the rocks increases with an increase 

in potash. This indicates that the potash-rich glassy phase of the rocks 

is the main carrier of potassium, uranium, radium, and probably thorium. 

The correlation between the amounts of uranium and potassium is a 

general expression of the correlation between the amounts of silica and 

uranium, because both silica and potassium increase in the residual magma 

during the first stages of magmatic differentiation. The author states 

that uranium is concentrated relative to potassium in the glassy groundmass in the later stages of magmatic differentiation by removal of some 

of the potassium into the crystalline phases.

The main Lassen sequence shows a positive correlation between uranium content and "relative alpha activity" ("a measure of a complex 

of phenomena involving over twenty different alpha-emitting nuclides in 

the U238, U235, and Th232 decay series"). A deviation from this trend 

shown by samples from the Cinder Cone (volcanic ash, andesite, and 

vesicular basalt) may be due to the selective leaching of uranium from 

some of the weathered samples.

The author believes that some of the uranium in the Lassen lavas is 

concentrated in zircon.

207
208 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

3 Adams, J. A. S., and Saunders, D. F., 1953, Uranium content of the lavas 

of Lassen Volcanic National Park, California [abs.]: Geol. Soc. 

America Bull., v. 64, p. 1389.

Nineteen samples of volcanic rocks from Lassen Volcanic National 

Park have been analyzed for uranium, sodium, potassium, and calcium. 

In addition, the alpha activities were measured with scintillometers. 

Uranium and potassium correlate positively, indicating that both tend 

to be enriched as differentiation proceeds toward more siliceous lavas. 

In the samples studied, the uranium is enriched about fourfold, while 

the potassium is enriched about threefold. The correlations with calcium, 

sodium, and total potassium plus sodium are less well defined than the 

potassium correlation. The correlation between potassium and alpha 

particle activity under standard conditions is rather well defined.

The correlation between alpha particle activity and uranium is not 

well defined when all samples are included. However, the samples that 

are furthest from the main trend may be considered special cases e. g., 

mudflows and rocks that were probably partially weathered and thus 

leached of part of their uranium. The main trend in the uranium content versus alpha particle activity indicates that the thorium/uranium 

ratio did not shift significantly during the differentiation of the Lassen 

lavas. Authors' abstract

4 Adams, J. A. S., Saunders, D. F., and Zeller, E. J., 1953, Uranium content, 

alpha particle activity, and K2O, Na2O, CaO analysis of obsidians, 

pitchstones, and tektites [abs.]: Geol. Soc. America Bull., v. 64, p. 

1389.

Seventy-four glassy rocks, including obsidians, pitchstones, and possible 

tektites have been analyzed for uranium fluorimetrically. Alpha activities 

have been measured with scintillometers. K2O, Na^O, and CaO have been 

determined on the flame photometer. The indices of refraction have also 

been measured. About half the samples are from the United States. The 

thermoluminescence of several samples was also measured, but no thermoluminescence was detected except in one obsidian from Ascension 

Island.

The uranium contents range from 0.77 ppm in an obsidian from Shizuoka 

Prefecture, Japan, to 16 ppm in an obsidian from Liparii, Italy. Few of 

these obsidians have as much as 0.50 percent CaO. A plot of alpha particle activity under standard conditions vs. uranium content has little 

scattering from linearity. This linearity indicates that the Th/U ratio 

is rather constant in the obsidians measured. Several geochemical interpretations of this linearity are advanced. Authors' abstract

5 Altschuler, Z. S., Clarke, R. S., Jr., and Young, E. J., 1954, Uranium in 

apatite [abs.]: Geol. Soc. America Bull., v. 65, p. 1225-1226.

Apatite contains only traces of uranium, yet as apatite is a minor constituent in most rocks and the major constituent of a few very large deposits it accounts, paradoxically, for both dispersal and concentration of 

uranium in nature.

Uranium is typically O.OOX percent of primary igneous apatite and 

O.OOX to 0.001X percent of sedimentary marine apatite. End-stage
URANIUM GEOLOGY OF IGNEOUS AND METAMOEPHIC ROCKS 209

igneous apatite may contain O.OX percent uranium. Analogously, marine 

reworked apatite becomes enriched in uranium from O.OOX to O.OX percent. This is demonstrated by the greater uranium contents of the 

texturally more complex phases within a single deposit.

Uranium can be secondarily leached from or introduced into apatite 

by ground water. These secondary changes are indicated by the existence 

of pronounced concentration gradients within single pebbles of apatite as 

well as by the redistribution of uranium among different mineral hosts in 

leached and altered sections of phosphorite.

It is proposed that uranium replaces calcium in the apatite structure. 

This is signified by several lines of investigation. Uranium and calcium 

contents parallel one another in sections of leached and altered phosphorite. 

Ionic radii of tetravalent uranium (1.05 A) and divalent calcium (1.06 A) 

are virtually identical, and most of the uranium in igneous, sedimentary, 

and bone apatite is tetravalent. Petrographic and chemical analyses and 

nuclear emulsion studies have shown that uranium in apatite is disseminated rather than locally concentrated. In addition, phosphate deposits 

are essentially devoid of uranium minerals. Authors1 abstract

Amstutz, G. C., 1951, Radioactivitatsmessungen an den Glarner Laven: 

Schweizer. naturf. Gesell. Verh., 131 Jahresvers., p. 138-139.

Two samples of quartz porphyry and four samples of spilite contain 

4.46, 3.08, 1.08, 1.12, 0.64 and 4.68 X 10~12 gRa perg, respectively (radium 

content calculated from the alpha activity of the rocks). The author 

believes that the radioactivity of these rocks is a function of their acidity, 

grain size, and proportion of minor accessories (sphene, apatite, and 

zircon). Part of the uranium and thorium is interstitial, the amount 

increasing with decreasing grain size. Structural defects in the rocks may 

contain much uranium or thorium, although most of the uranium and 

thorium probably substitutes for calcium in the minor accessory minerals.

Barth, T. F. W., 1938, Radium and the petrology of certain granites of 

Finland: Am. Jour. Sci., 5th ser., v. 35-A, p. 231-245.

The radium content of various types of Finnish granites is given and is

compared with the percentages of biotite, potash, and ferrous oxide in

these granites. In each group of granites, the total amount of radium

increases with the biotite content. No correlation was found between

radium and potash content or between radium and ferrous oxide content*

Becraft, G. E., 1956, Uranium deposits of the Boulder batholith, Montana:

Internat. Conf. on Peaceful Uses of Atomic Energy, Geneva

1955, Proc., v. 6, Geology of uranium and thorium, p. 270-274; U. S.

Geol. Survey Prof. Paper 300, p, 117-121.

This paper is a discussion of the geology of uraniferous vein deposits in 

the Boulder batholith area, but it has been included here for the following 

observation. At the W. Wilson mine, "a few secondary minerals, mainly 

metatorbernite, meta-autunite, and uranophane, are sparsely distributed 

along and adjacent to fractures [in quartz monzonite] outside of the ore 

bodies, indicating the transportation and redeposition of some of the 

uranium by meteoric water."

459423 58 2
210 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

9 Billings, M. P., and Keevil, N. B., 1946, Petrography and radioactivity of 

four Paleozoic magma series in New Hampshire: Geol. Soc. America 

Bull., v. 57, p. 797-828.

Four magma series are recognized in western and central New Hampshire. 

This paper describes the rocks of these series and their radioactivity in 

terms of alphas per milligram of rock per hour.

The White Mountain magma series of Mississippian(?) age consists of 

alkalic rocks ranging from gabbro to granite. Radioactivity is lowest in 

the gabbro, norite, and diorite, and increases 4.15 times to a high of 4.56 

alphas per mg per hr in samples of biotite granite. The radioactivity of 

individual rock specimens ranges within wide limits, indicating that the 

radioactive elements are irregularly distributed in the rocks. The increase 

of radioactivity in the granitic rocks is associated with a decrease in the 

potash feldspar, biotite, and apatite content; it is caused primarily by the 

presence of allanite and secondarily by an increase in the amount of zircon.

The rocks of the New Hampshire magma series of Late Devonian (?) age 

range from diorite to granite. The radioactivity increases 4.24 times from 

the dioritic to the granitic rocks of the series. The highest average radioactivity of the series (2.74 alphas per mg per hr) was detected in samples of 

the Long Mountain granite. There are not enough data on the percentages 

of the accessory minerals to explain this distribution of radioactivity.

The Oliverian magma series of Middle Devonian (?) age consists of quartz 

diorite, granodiorite, quartz monzonite, and granite. The average radioactivity increases from 1.04 alphas per mg per hr in the quartz diorite to 

2.67 alphas per mg per hr in the granite. The lack of data on the percentages of the accessory minerals precludes an explanation of this increase 

in radioactivity.

The rocks of the Highlandcroft magma series range from diorite to 

granite. The average radioactivity increases from 0.59 alphas per mg per 

hr in the diorite to 1.44 alphas per mg per hr in the granodiorite. No 

quartz monzonite or granite was available for study.

In all series there was a general increase in radioactivity toward the 

granitic end. This increase is not caused by an increase in potash or biotite 

content (references 7 and 21). Except for the White Mountain series, the 

available data are too few to determine whether or not the quantity of 

radioactive accessory minerals increases toward the granitic end. Perhaps 

some of the minerals in the granitic rocks have a higher percentage of 

radioactive elements than the same minerals in the gabbroic rocks, because 

of a relatively higher concentration of radioactive elements in the later 

magma.

10 Brown, Harrison, Blake, W. J., Chodos, A. A., Kowalkowski, Richard, McKinney, C. R., Neuerburg, G. J., Silver, L. T., and Uchiyama, Aiji, 

1953, Leaching studies of interstitial material in igneous rocks [abs.]: 

Geol. Soc. America Bull., v. 64, p. 1400-1401.

Chemical studies of a group of plutonic igneous rocks indicate that 

significant proportions of many of the minor elements may be readily 

removed by leaching in the pulverized state with cold, dilute acid under 

controlled conditions. Comagmatic rocks (southern California batholith) 

and rocks of widely diverse geographic location and geologic history yield 

soluble material of rather uniform gross composition. Minor elements 

extracted show considerable variation, but many are considerably concen-
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 211

trated with respect to the gross rock. Up to 40 percent of the radioactive 

elements and rare earths in a granite may be found in leachable material, 

representing considerably less than 1 percent of the total weight of the rock. 

Greatest trace-element enrichment occurs where ionic radius and charge 

hinder admission of the element to the major mineral phases.

Several sources may contribute to the acid leaches. These include, 

in addition to solution of major minerals, minor amounts of alteration 

minerals, such as calcite and zeolites; certain accessory minerals, particularly if metamict; and, apparently, submicroscopic material dispersed 

along fractures and grain boundaries. Mechanical fractionation according 

to particle size and mineral composition aids the recognition of the individual contributions from the various sources. Special efforts to control 

external contamination have been made.

The dispersed submicroscopic material, here called "interstitial," plays 

an important, generally unrecognized, role in the trace-element character 

of igneous rocks. It particularly affects trace-element determinations and 

age measurements on rocks and rock minerals and may yield important 

information on many rock-forming and rock-modifying processes. 

Authors' abstract

11 Brown, Harrison, and Silver, L. T., 1956, The possibilities of obtaining 

long-range supplies of uranium, thorium, and other substances from 

igneous rocks: U. S. Geol. Survey Prof. Paper 300, p. 91-95.

The authors discuss the distribution of uranium and thorium in igneous 

rocks and the possibilities of procuring a supply of these elements from 

igneous rocks.

The ionic radii and charges of uranium and thorium enable them to 

substitute for other elements (that is, zirconium and calcium) in the 

crystal lattice of certain accessory minerals of granite, such as zircon, 

allanite, sphene, and apatite.

Much of the uranium, thorium, and other minor elements in igneous 

rocks can be removed with a simple acid leach. The gross composition of 

leaches from some granites, granodiorites, and aplites are given.

Alpha-track autoradiograph studies of the distribution of the leachable 

radioactive elements in granites indicate that most of the radioactivity is 

concentrated in the microscopic accessory minerals, some of the activity 

occurs in the common rock-forming minerals, and a small part of the 

radioactivity is caused by interstitial material such as microscopic 

discrete minerals and submicroscopic particles.

The more soluble accessory minerals, such as apatite, allanite (particularly if metamict and altered), thorite, and bastnaesite, contribute most 

of the radioactive elements to the leach extractions. Allanite and its 

alteration products appear to be an important constitutent of interstitial 

material in granites and the principal source of radioactivity in granite.

12 Coats, R. R., 1956, Distribution of uranium and certain other trace 

elements in felsic volcanic rocks of Cenozoic age of the Western 

United States: Internat. Conf. on Peaceful Uses of Atomic 

Energy, Geneva 1955, Proc., v. 6, Geology of uranium and thorium, 

p. 248-251.

 1956, Uranium and certain other trace elements in felsic volcanic 

rocks of Cenozoic age in Western United States: U. S. Geol. Survey 

Prof. Paper 300, p. 75-78.
212 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Samples of rhyolites and dacites from Washington, Oregon,, Idaho, 

Montana, Wyoming, Colorado, Utah, Nevada, California, and Arizona 

were analyzed fluorimetrically for uranium, chemically for fluorine, and 

spectrographically for boron, beryllium, lanthanum, lithium, niobium, 

xenon, tin, lead, and zirconium. The geographical distribution pattern 

and the statistical relations of these elements are discussed.

The data were assembled in an attempt to determine whether or not 

uranium provinces exist in volcanic rocks of the Western United States. 

The author concludes that such provinces do exist and discusses the 

probable causes of these regional variations in uranium content of rhyolitic 

and dacitic rocks.

13 Dalton, J. C., Golden, J., Martin, G. R., Mercer, E. R., and Thompson, 

S. J., 1953, Recent studies on iron meteorites III, Determination of 

the uranium and thorium contents: Geochim. et Cosmochim. Acta, 

v. 3, p. 272-287.

The authors describe the following methods for the determination of the 

uranium and thorium content of 10-to-100 gram samples of iron meteorites: 

radon-thoron, fluorimetric, and alpha-particle counting with a scintillation 

counter. The uranium and thorium contents of 15 meteorites, determined 

by the various methods (not every sample was tested by all methods) are 

presented in tabular form. Two of the 15 samples are from the United 

States. The Carthage meteorite (Tennessee) and the Brenham Township 

meteorite (Kansas, iron phase) have uranium contents of 0.41 ± 0.05 X10~8 

g per g and 0.06 ± 0.02 X10~8 g per g, respectively (determined by the 

fluorimetric method).

The authors believe that the results obtained by the fluorimetric and 

scintillation counting methods are the most reliable.

14 Davidson, C. F., 1951, The distribution of radioactivity: Mining Mag. 

[London], v. 85, p. 329-340. See p. 330-331.

This paper is mainly a summary of information about the distribution of 

radioactivity in various rock types.

Radioactive elements in igneous rocks are concentrated in the more acid 

phases of the lithosphere. Exclusive of potassium, the radioactive elements 

in granite are concentrated manly in the accessory minerals, particularly 

in monazite, xenotime, allanite, zircon, apatite, sphene, thorite, and rarer 

refractory minerals of the niobate-titanate type. Biotitic rocks are somewhat more radioactive than hornblendic rocks. The roof and marginal 

phases of granite masses are likely to be the most radioactive. It can be 

shown by autoradiographs that most of the radioactivity in an unaltered 

granite is confined to the heavy minerals, whereas in rocks altered by 

pneumatolysis or by ground waters, the radioactive elements are distributed 

along cracks within and as coatings on the feldspars and quartz. Much of 

the uranium in granite seems to be relatively soluble in percolating ground 

waters and can be leached away to be redeposited as films of secondary 

uranium minerals along joint planes and fissures. In North America, 

the average thorium/uranium ratio of granitic rocks seems to be 3.4:1 

and that of intermediate rocks, 4.0:1.

15 Davis, G. L., 1947, Radium content of ultramafic igneous rocks I, 

Laboratory investigations: Am. Jour. ScL, v. 245, p. 677-693.

This reference is concerned mainly with the description of the direct-
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 213

fusion vacuum technique used to measure the radium content of some 

ultramafic rocks. The results of analyses of a group of these rocks and 

minerals are presented in tabular form. The radium content is expressed 

in terms of the unit, 10~12 grams of radium per gram of rock. The following average radium contents of various magma suites are given:

AVERAGE NUMBER 

RADIUM OF 

CONTENT SAMROCK TYPE 10~M g/g PLES

Ultramafic magma suite (dunites, partially serpentinized dunites and serpentine)_______________ 0. 009 19

Ultramafic magma suite (contact rocks serpentine) _ . 059 5 

Ultramafic rocks of basaltic magma suite, crystal accumulates_______________________ ______ . 010 3

Secondary peridotite magma suite _____________ . 009 4

Meteorite:

Metal portion_______ ______ _ ______ .0059 1

Olivine portion.-_______________________ .0004 1

The minerals and mineral separates that were analyzed include chromite, 

diopside, bronzite, olivine, tremolite, and serpentine minerals.

Measurements of the radium content of the chromite and olivine fractions 

of a sample of dunite from Addie, N. C., indicate that much of the radium 

of the rock is contained in one or more of the minor minerals, tremolite, 

serpentine, talc, and chromite: that is, serpentine and talc account for 30 

percent of the total radium, although these minerals comprise only about 5 

percent of the rock.

16 Davis, G. L., 1950, Radium content of ultramafic igneous rocks III, 

Meteorites: Am. Jour. Sci., v. 248, p. 107-111.

The radium content of some pallasites and iron meteorites was measured 

by a refinement of the vacuum fusion technique (reference 15), and is expressed in the units, 10~12 grams of radium per gram of sample. The 

uranium content (calculated from the radium content) is given as units of 

10~8 grams per gram.

TTRANIRADIUM 10~12 UM 10-" 

ROCK TYPE LOCALITY g/g ff/g

Average 

0. 0011 0. 33

Medium octahe- Mesa Verde, Colo___ 

drites_________. Carthage, Tenn______

Tunda, Q ueensland _ _. 

Octahedrites______ Edmonton, Ky_._____

Glorieta, N. Mex_____ 

Hexahedrites..____ Sierra Gorda, Chile.__

Cedartown, Ga_______

Pallasites--------- Salta, Argentina..______ 1 Average of metal fracAntofagasta, Chile..____ [ tion.

Brenham, Kans______ JO. 0042 1. 23

Amphoterite____ Shaw, Colo_________ . 0164 ±. 0007 4. 8 

Stone.._______ Cumberland Falls, Ky_ . 0034±. 0013 1.0

The results indicate that (a) the radium content of meteorites is low or lower 

than that of most ultramafic rocks, and (6) the metal portion of pallasites contains 

more radium than the silicate portions.
214 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

17 Davis, G. L., and Hess, H. H., 1949, Radium content of ultramafic igneous 

rocks II, Geological and chemical implications: Am. Jour. Sci., v. 

247, p. 856-882.

The radium and uranium content of the ultramafic igneous rocks and 

their constituent minerals given in this article are the same as those 

presented in reference 15.

The analyses demonstrate the decrease in radium content with an 

increase in the mafic character of the rocks. The authors believe that 

most of the uranium in samples of ultramafic rocks (formed by accumulation of early crystals from a basaltic magma) was contained originally in 

the small amount of interstitial liquid trapped between the crystals.

In ultramafic rocks of the secondary peridotite suite, the radium content 

decreases with an increase in iron. In rocks of the primary peridotite 

suite, there seems to be a general correlation between the water and radium 

contents.

Analyses of minerals of ultramafic rocks indicate that most of the radium 

content of the rocks is concentrated hi the late-stage minerals tremolite, 

talc, and kammerite.

Petrographic descriptions of the rocks are appended.

18 DeVore, G. W., 1955, The role of adsorption in the fractionation and 

distribution of elements: Jour. Geology, v. 63, p. 159-190.

This article is included because it is of general theoretical application, 

although it does not discuss uranium.

Adsorption is advanced as a principal factor in the distribution and 

fractionation of minor constituents in minerals. The effects of adsorption 

on the processes of nucleation and crystal growth are considered as important factors in controlling compositional relationships between coexisting 

minerals and possibly determining certain mineral assemblages. The 

possibility that adsorption during crystal growth may cause slight disequilibrium conditions is indicated. The changes of the trace element 

content in certain metamorphic rocks between different metamorphic 

facies are illustrated, and the possibility is discussed that such metamorphic 

transformations may provide a liberation of ore-forming materials. 

Author's abstract

19 Eckel, E. B., and Lovering, T. S., 1935, Microlite from Ohio City, Colorado 

Exhibit V: Natl. Research Council, Rept., Comm. on Measurement 

of Geol. Time, 1935, p. 77-79.

A variety of microlite was identified in a group of lepidolite-bearing 

pegmatite dikes, in schists, in the Ohio City area, Gunnison County, Colo. 

The microlite, associated with lepidolite and albite, occurs as rounded 

dark-brown grains. A chemical analysis of the microlite is given, which 

includes a uranium content of 1.49 percent.

20 Emmons, R. C., Reynolds, C. D., and Saunders, D. F., 1953, Genetic and 

radioactivity features of selected lamprophyres: Geol. Soc. America 

Mem. 52, p. 89-99.

The authors believe that lamprophyre dikes and their associated radioactive materials are "(1) the products of very late reactions in the cooling
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 215

history of an igneous rock, (2) derived from the walls of a fracture under 

the influence of differential pressures created dilatantly, and (3) commonly 

gathered from small tributary fractures into larger fractures, providing a 

gradation from small dark 'deuteric veinlets' through dikelets to sizeable 

dikes."

Radioactivity data of some lamprophyres in Wisconsin are presented in 

support of this theory.

21 Evans, R. D., and Goodman, Clark, 1941, Radioactivity of rocks: Geol. 

Soc. America Bull., v. 52, p. 459-490.

Although numerous previous measurements of the radioactivity of 

terrestrial materials have been made, most of these researches are of 

qualitative value only in their applications to geology, geophysics, and 

cosmology because of inadequate recognition of the analytical care necessary in order to obtain reliable results. In the present study of the 

radioactivity of terrestrial materials, a systematic program of standardization, calibration, and interchecking has been followed throughout. As 

a general program of helium-age research, several hundred radioactivity 

measurements have been made. These results represent the most reliable 

collection of radioactivity determinations which have yet been made 

within the range of concentrations involved. By combining these newer 

measurements with the limited number of well-authenticated earlier 

analyses available, average values have been obtained as follows: 1.37± 

0.17X10-12 gRa per g for 43 acidic igneous rocks, 0.51 ±0.05X10-" 

gRa per g for 7 intermediate igneous rocks, 0.38 ± 0.03 X10~12 gRa per g 

for 54 basic igneous rocks, and 0.57±0.08X10~12 gRa per g for 28 sedimentary rocks; 3.0±0.3X10-6 gU per g, 13±2.0X10-« gTh per g, and a 

Th/U ratio of 2.6 for 6 intermediate igneous rocks; 0.96±0.11X10-* gU 

per g, 3.9±0.6X10-6 gTh per g, and a Th/U ratio of 4.0 for 34 basic 

igneous rocks. These values are substantially lower than those obtained 

by Jeffreys in a compilation of most of the measurements reported prior 

to 1936. The present averages show a more marked decrease of radioactivity with increasing basicity; the Th/U ratios are considerably greater 

than those compiled by Jeffreys and are in better agreement with those 

to be expected from geochemical considerations. Two ultrabasic rocks 

were found to have radioactivities comparable to the low values for iron 

meteorites. Specific inaccuracies in earlier investigations have been 

discovered. Estimates are made of the rate of production of heat by 

radioactive decay based on the above average values for the different 

rock types. Authors' abstract

22 Evans, R. D., and Williams, Howel, 1935, The radium content of lavas 

from Lassen Volcanic National Park, California: Am. Jour. Sci., 5th 

ser., v. 29, p. 441-452.

Chemical analysis and radium contents are given for 17 samples of lavas 

from Lassen Volcanic National Park, Calif. The lavas range in composition from basaltic to rhyolitic (dacites and andesites predominate) and in 

age from Tertiary to Recent. Brief petrographic descriptions of the samples 

are given.

The radium content was determined using the direct-fusion furnace
216 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

technique. The average radium content of the various rock types is as 

follows:

NUMBER

OF RADIUM 

ROCK TYPE SAMPLES 10 12 g/g

Basalt ___ _________ _ _ ___ _____

Andesites ____ ___ ____ __

Dacites ___ ____ _ _ ___ _

___ ___ __ 2

3

4

7

0. 33

.34

.48

.80

An illustration comparing the radium, silica, and potash content of the 

lavas indicates that the radium content increases with the alkalies, especially potash, and that it is not directly proportional to the silica content.

A clean separation of constituent minerals of the Lassen lavas was not 

possible, although partial fractionation was achieved with two samples, 

as shown.

RADIUM RADIUM 

CHAOS CRAGS DACITE 10~12 g/g OLD LASSEN DACITE- 10~12 g/g

Plagioclase phenocrysts__ 0. 47 Lava as a whole________ 0. 81

Strongly magnetic heavies Light separates (plagio-

(magnetite, hornblende, clase, pale glass)____ _ .81

some glass)____________ .85 Heavy separates (iron

Weakly magnetic heavies ores, biotite, horn-

(biotite, minor horn- blende)______________ . 68

blende)__________ .83

Residual glass,___________ ! !(?)

Dacite [in above fraction]__ .67

Dacite [another sample;

same locality]____ . 93

In the Chaos Crags dacite the residual glass (acid, potash-rich) was the 

most radioactive. No marked concentration of radium in the micas was 

noted. The variation in radium content of the two mineralogically 

similar dacite samples implies a pronounced inhomogeneity of radium 

distribution within a single lava protrusion.

The authors found no marked concentration of radium in the heavy 

minerals of the Old Lassen dacite; they state that much of the radium is 

probably in the residual glass or its microlithic inclusions.

23 Foye, W. G., and Lane, A. C., 1934, Correlations by radioactive minerals 

in the metamorphic rocks of southern New England: Am. Jour. 

Sci., 5th ser., v. 28, p. 127-138.

Three samples of uraninite taken from pegmatite within a few feet of 

the pegmatite-schist contact in the Strickland quarry, Portland, Conn., 

have an average uranium content of 78.78 percent. Five samples of 

uraninite from pegmatite from the Hale quarry, also in Portland, Conn., 

have an average uranium content of 71.32 percent.

Four layers of a single crystal of uraninite were analyzed chemically. 

The uranium content ranges from 79.00 percent in the interior of the 

crystal to 80.14 percent in the outer layer.

The paper is mainly concerned with the application of the data to age 

determination studies.
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 217

24 Furcron, A. S., 1955, Prospecting for uranium in Georgia, Part I: Georgia 

Mineral Newsletter, v. 8, p. 38-46.

Uranophane, thinly coated by hyalite, occurs as a yellow coating on 

joint planes of the Stone Mountain granite, in quarries in the vicinity of 

Stone Mountain, Ga. Two samples of the yellow material contained 

40.10 and 52.08 percent uranium, respectively.

Uranium minerals also have been found in several pegmatites in Georgia. 

In Lamar County, yellow and green secondary uranium minerals occur 

as incrustations on joints and in cracks of a coarse-grained pegmatite. 

Soddyite and beta-uranophane in close association occur as inclusions in 

muscovite. A sample of the pegmatite contained 0.22 percent uranium. 

A brownish-black heavy primary uranium ore mineral occurs as veinlets 

and segregations in fresh pegmatite in Greene and Jasper Counties. An 

X-ray examination of the mineral showed it to be metamict.

25 Gabriel, V. G., 1951, The significance of radioactivity measurements in 

separating granites from granitized (metamorphic) rocks: Mines 

Mag. [Colorado], v. 41, p. 33-34, 39.

The author proposes that the radioactivity of intrusive igneous rocks 

should be significantly different from that of granitized sediments. On 

the basis of published radioactivity measurements, he states that granitic 

rock bodies should have a higher concentration of radioactive elements at 

the border, whereas the radioactivity of metamorphic rocks should be 

evenly distributed throughout the rock mass.

26 Goldschmidt, V. M., 1954, Geochemistry: Oxford, England, Clarendon 

Press, 730 p.; edited by Alex Muir. See p. 562-567.

Part 1 of this book discusses the scope and development of geochemistry, the distribution of the elements during the evolution of the earth, 

the evolution of magmatic rocks, a quantitative treatment of geochemical processes, the chemical composition of the cosmos and of its various 

separate mass concentrations, and some principles of crystal chemistry in 

relation to geochemistry. The second part is devoted to the geochemistry 

of the elements.

The ionic radius of quadrivalent uranium determines its distribution 

in the primary minerals of igneous magmas. A higher concentration of 

uranium generally is found in acidic granitic magmas than in syenites or 

felspathoid syenites. That uranium enters zircon in the 4-valent state is 

demonstrated by the characteristic absorption band spectrum of uraniferous zircon, which is very closely related to the absorption line spectrum 

of the U+* ion.

27 Gottfried, David, 1953, Distribution of uranium in igneous complexes, 

in Geologic investigations of radioactive deposits Semiannual progress report, June 1 to Nov. 30, 1953: U. S. Geol. Survey TEI-390, 

p. 240-244, issued by U. S. Atomic Energy Comm. Tech. Inf. Service 

Ext., Oak Ridge, Tenn.

The pertinent section of this article is reprinted in its entirety as follows: 

A total of 300 uranium determinations on 150 rock samples have been 

completed on carefully selected rocks from the following areas: Southern 

459423 58 3
218 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

California batholith; Sierra Nevada; Idaho batholith; San Juan lavas; 

White Mountain magma series, New Hampshire; and Front Range, Colo.

These igneous complexes underlie vast areas and are fairly typical of 

the average rocks exposed in the earth's crust. A general comparison of 

these areas indicates that for rocks of similar composition, the southern 

California, Sierra Nevada, and Idaho batholiths are similar in uranium 

content. The distribution of uranium in the San Juan lavas appears to 

be nonsystematic and a plot of their uranium content against their composition is erratic. The White Mountain magma series is highest in 

uranium content, approximately twice that of the southern California 

batholith. These soda-rich granites contain from 10 to 14 ppm uranium. 

A study of their accessory minerals showed abundant and highly radioactive zircon, monazite, xenotime, allanite, pyrochlore, and the rare mineral chevkinite. The Front Range granites appear to contain 1% times 

more radioactivity than the southern California batholith. To determine 

the variability of uranium content in an apparently uniform rock type, 

a 12-mile traverse was made across a stock of the Boulder Creek granite 

near Boulder, Colo. Samples were collected at half-mile intervals. The 

uranium content of the granite at the contact was 15 ppm U, and gradually decreased to 1.0 ppm U for the sample, 12 miles away from the contact.

Monomineralic concentrates of the major and minor accessory minerals 

have been made on almost all of these rocks. In view of the large number 

of uranium determinations required, only a few of the major minerals 

have been analyzed individually for uranium. The radioactivity of the 

accessory minerals has been studied in greater detail, as they contribute 

significantly to the total radioactivity of the rock. This has been made 

possible by alpha counting techniques which measures accurately and 

rapidly the radioactive content of these minerals. Among all the accessories, zircon is most common to all the igneous rocks thus far studied, 

although monazite, xenotime, and thorite appear to be more common 

than previous work has indicated. In addition the rare radioactive minerals such as pyrochlore and chevkinite were found in granites of the 

White Mountain magma series. The radioactivity of the zircons separated from a related group of rocks such as the southern California 

batholith has been investigated. There is a marked increase of the alpha 

activity of the zircon as the rocks from which they were separated became 

more acidic.

28 Gross, W. H., 1952, Radioactivity as a guide to ore: Econ. Geology, v. 47, 

p. 722-742.

The author suggests that the distribution of radioactivity in stocks and 

batholiths can serve as a useful guide to ore. Of the Canadian intrusives that were examined, those with associated ore bodies exhibited higherthan-normal radioactivity in the igneous rocks near ore structures; no 

such concentration was found in those intrusives barren of ore. The method 

is based on the following theoretical considerations and supporting evidence.

1. "Late solutions, which include the pegmatite and hydrothermal stages 

in a crystallizing intermediate to acid magma, will be relatively high in the 

radioactive elements." Evidence of the association and concentration of 

radioactive minerals with the products of late crystallization (such as 

siliceous rocks reference 23 and pegmatites) and the concentration of 

radioactive elements around the grain boundaries of essential rock-forming 

minerals (references 33 and 81), supports the validity of this proposition.
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 219

2. "Late solutions from crystallizing magmas will tend to flow to areas of 

lower pressure. Normally, these solutions will be moving down a temperature gradient so that deposition from the solution will take place." In an 

intrusive, the direction of flow of late magmatic solutions will be toward 

areas of concentration of the late-crystallizing products of the magma, and 

hence toward areas of higher-than-normal radioactivity.

3. "Late solutions which are relatively high in radioactivity may or may 

not be ore carriers, but normally they will move along the same structural 

channelways as the ore." A comparison of the alpha activity of samples of 

associated intrusive rocks, ore, and pegmatites indicates that the igneous 

rocks have a higher radioactivity than the ore and a lower radioactivity 

than the pegmatites.

4. "The primary distribution of radioactivity in stocks and batholiths 

will not be seriously affected by alteration changes of later hypogene 

solutions." The radioactivity in and around six Canadian intrusives 

examined decreases from the granitic intrusive rocks through the altered 

intrusive to the ore.

"If the four assumptions made above are valid, it can be expected that 

in such igneous bodies as stocks and batholiths there will be a broad area of 

higher-than-normal radioactivity in the vicinity of relatively low pressure 

areas, such as major fault and fracture zones, which occur nearby. The 

association of radioactivity in igneous rocks to major structures will occur 

whether the so-called igneous body and the ore is formed from cooling 

magma or from heated and recrystallized sediments. Finally, the structures 

that are indicated by areas of higher-than-normal radioactivity may act as 

channelways for ore solutions or, in fact, as a locus for the ore itself. It 

follows, then, that zones of higher-than-normal radioactivity in large 

igneous-like masses will occur in the vicinity of related ore bodies that are 

controlled by major structural features."

29 H6e, Arlette, Derville, R. P., and Jarovoy, Michel, 1954, Determination of 

the radioactivity of the Quincy granite by the photographic method: 

Am. Jour. Sci., v. 252, p. 736-744.

Approximate uranium and thorium contents of powdered Quincy (Mass.) 

granite have been determined with nuclear photographic emulsions. 

[Results of analyses of two powdered samples: 5.1 and 2.1X 10~6 gU per gj 

Compared with previous results, obtained by different methods, the new 

values have a wide range, because the radioelements are concentrated in 

distinct centers scattered haphazardly through the rock. The radioactive 

centers have been localized in thin sections by the emulsion technique; 

they are found chiefly in sphene and ilmenite associated with riebeckite. 

The nuclear emulsion technique, which delineates the distribution of radioactive atoms in various accessory minerals, may be useful in the study of 

the problem of geologic age of rocks. Authors' abstract

30 Hewett, D. F., and Glass, J. J., 1953, Two uranium-bearing pegmatite 

bodies in San Bernardino County, California: Am. Mineralogist, v. 

38, p. 1040-1050.

The paper is a mineralogic description of two uranium-bearing pegmatites 

in San Bernardino County, Calif.

The Cady Mountains pegmatite body, near Hector, is in the central part 

of a quartz monzonite mass. The presence of betafite (a niobate and titanate of uranium) is of interest because of its rarity in American pegmatites.
220 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

This mineral contains 10.68 percent uranium. Spectrographic analyses are 

given of the betafite, cyrtolite, and niobian anatase found in the Cady 

Mountains pegmatite.

The Pomona Tile quarry pegmatite locality is in quartz monzonite. 

The uranium-bearing minerals found were euxenite and an unidentified 

mineral. Two samples of the euxenite contained 13.9 and 14.5 percent 

uranium, respectively. The unidentified uranium-bearing mineral contains, as determined by qualitative spectrographic analysis, from 6 to 10 

percent uranium. Spectrographic analyses of the two minerals are given.

31 Holmes, Arthur, 1931, Radioactivity and geological time, in Physics of 

the earth IV, The age of the earth: Natl. Research Council Bull. 

80, pt. 4, p. 321-355.

This report is concerned mainly with the application of radioactivity 

data to age determinations. Uranium analyses, taken from published 

literature, are given for the following minerals from pegmatites. Uranium 

content, in percent, is shown in parentheses. Uraninite (55.18, 56.44), 

mackintoshite (19.75) yttrialite (1.45, 0.69), fergusonite (6.07) from 

Baringer Hill, Llano County, Tex.; uraninite (66.90) from the Ingersoll 

claim, Keystone, S. Dak.; samarskite (3.55, 3.72) from Devil's Head 

Mountain, Douglas County, Colo.; samarskite (7.14) from Petaca, N. Mex.; 

uraninite (74.30, average of 5) from Branchville, Conn.; uraninite (71.32, 

average of 5) from Glastonbury, Conn.; allanite (0.11) from Blueberry 

Mountain, Boston, Mass.; and uraninite (76.96, 77.77) from the Spruce 

Pine district, North Carolina,

32 Hurley, P. M., 1950, Distribution of radioactivity in granites and possible 

relation to helium age measurement: Geol. Soc. America Bull., v. 61, 

p. 1-8.

Granulated samples of acidic igneous rocks have been found to give a 

much higher rate of emission of alpha particles than corresponds to the 

known total contents of uranium and thorium. Abnormally large residual 

ranges of the alpha particles suggest a surficial distribution of the radioactive elements on the surfaces of the granules in the form of secondary 

mineral coatings. Most of the alpha-particle activity can be removed by 

dilute hydrochloric acid, leaving an activity corresponding to the low 

content of uranium and thorium found in sandstones and arkoses, in which 

the essential mineral grains of granites have been rounded and cleaned 

by attrition. The proportion of surficial activity appears to be less for 

granite samples taken from considerable depth below the surface than 

for samples from the zone of surface-water saturation. Losses of activity by 

acid treatment appear to be related to the degree of retentivity of helium in 

different igneous rocks types. Determination of the helium-age ratio before 

and after acid treatment suggests that the essential rock minerals contain 

as much helium as they should commensurate with their age and with the 

quantity of radioelements uniformly distributed within them, and not 

removable by acid. The low ratio of helium to radioactivity for the rock 

as a whole may be due either to loss of helium from highly radioactive 

areas that are easily affected by acid and thus also probably by ground 

waters or to actual supergene enrichment of radioelements late in the 

history of the rock. Author's abstract
URANIUM GEOLOGY OF IGNEOUS AND METAMORPH3C ROCKS 221

33 Hurley, P. M., and Fairbairn, H. W., 1955, Ratio of thorium to uranium 

in zircon, sphene, and apatite [abs.]: Geol. Soc. America Bull., v. 66, 

p. 1578.

Zircon, sphene, and apatite are important host minerals for uranium and 

thorium in igneous and metamorphic rocks. Several dozen samples from 

widely scattered localities were analyzed for these elements to observe 

variations in their relative abundance. Analyses were made by scintillation 

spectrometer.

The ratio Th/U is remarkably constant for accessory zircons separated 

from individual granite plutons. Average values for the following areas 

are: Eastern Massachusetts, 0.6; Nova Scotia, 0.2; Northern Maine, 0.6; 

Sudbury, Ontario, 0.3; miscellaneous, 0.6. In granite zircons in general, 

therefore, 90 percent of the radioactivity is due to the uranium series.

In large crystals of zircon from pegmatites the ratio is more varied with 

a tendency to be higher in the more radioactive samples. Average ratios 

for areas are: Ontario, 0.5; Carolinas, 2.2; Oklahoma, 5; Ceylon, 0.1; 

miscellaneous, 1.2.

Samples of sphene were found to be quite varied but with average values 

similar to pegmatite zircons. Coarsely crystalline apatite samples were 

found to be relatively rich in thorium with ratios commonly exceeding 10. 

The average ratio for accessory apatite is 1.3. If igneous rocks have an 

average Th/U ratio of about 3, there must be an enrichment of thorium 

relative to uranium elsewhere in the rock, other than in these minerals. 

Authors' abstract

34 Hutchinson, R. M., Jaffe, H. W., and Gottfried, David, 1954, Magmatic 

trends and absolute age determinations of Precambrian intrusives of 

central Texas [abs.]: Geol. Soc. America Bull., v. 65, p. 1266.

Harker variation diagrams have been plotted for 17 intrusions: 8 Town 

Mountain type with 1 associated aplite; 1 Oatman type; 2 Sixmile type; 

5 aplogranites, and 1 granite porphyry (llanite).

Town Mountain type granites occupy positions of lower and intermediate 

silica content. Aplogranites are restricted to high-silica positions. The 

aplite falls within the aplogranite range suggesting the aplogranites may 

be late-stage differentiates of Town Mountain type granites. Llanite falls 

within the more acid of the Town Mountain type granites and probably 

is the approximate aphanitic equivalent.

Oatman type granite is intermediate between aplogranites and Town 

Mountain granites. Sixmile granites fail to fit the curves, suggesting a 

separate line of magmatic descent.

Age determinations are as follows: 

Town Mountain type intrusions:

Wolf Mountain phacolith________________ 917 million years

Legion Creek mass.._--___________________ 893 million years (av.)

Enchanted Rock pluton________________ 815 million years (av.)

Sixmile type: Sixmile mass _____________________ 822 million years

Oatman type: Sharp Mountain mass____________ 857 million years (av.)

Zircon samples from Wolf Mountain phacolith and Legion Creek mass 

gave low-alpha counts compared with those from Enchanted Rock pluton
222 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

and suggest a different period of intrusion or possibly fractionation with the 

uranium and thorium having concentrated in the younger fraction. Highalpha counts of zircon from Sixmile mass and Sharp Mountain mass also 

indicate possible fractionation. The Town Mountain type granites 

probably had a common magma source, with different periods of intrusion. 

Field relations confirm the age determinations. Sixmile mass crosscuts 

and contains xenoliths of Wolf Mountain phacolith. Enchanted Rock 

pluton contains xenoliths of schist recrystallized by intrusion of the Legion 

Creek mass. Authors' abstract

35 Button, C. O., 1951, Allanite from Yosemite National Park, Tuolumne 

County, California: Am. Mineralogist, v. 36, p. 233-248.

The article is mainly a mineralogic description of allanite from two 

localities in Yosemite National Park, Calif. One of the samples from 

quartz-orthoclase pegmatite boulders in scree in the south slope of Ragged 

Peak contains 0.015 percent uranium. A chemical analysis of the mineral 

is given. An autoradiograph demonstrated inhomogeneity in the crystal. 

A few dense spots on the plates indicated areas of intense radioactivity in 

the allanite, but these radioactive areas could not be correlated with 

specific particles in the mineral.

36 Jahns, R. H., 1953, Distribution of rare elements within granites and 

granitic pegmatites [abs.]: Geol. Soc. America Bull., v. 64, p. 1440.

The distribution and mode of occurrence of rare elements in a given 

igneous rock are governed by several well-known factors, chiefly: (1) composition of the magma, including concentrations of the rare-element ions; 

(2) pressure-temperature conditions during crystallization of the magma; 

and (3) charge, size, polarizability, and other properties of the rare-element 

ions.

During crystallization of a magma under a given set of conditions, a 

rare-element ion may enter the structure of a common mineral (gallium 

in feldspar) or a rarer mineral (cesium in beryl); it may enter, or be 

trapped by, a much less appropriate mineral structure (tin in muscovite), 

followed in some instances by transfer to an exsolved mineral; it may be 

concentrated in the residual fluid until it forms a mineral of its own (cesium 

in pollucite); or it may remain dispersed in the residual fluid until ultimately 

it is bound to the surface of the nearest crystal lattice.

The first three mechanisms seem to account satisfactorily for the distribution of beryllium, cesium, rubidium, thallium, lithium, niobium, 

tantalum, the rare earths, tin, titanium, tungsten, molybdenum, uranium, 

thorium, and other rare elements in granitic pegmatites and some granites. 

The fourth mechanism evidently becomes prominent during crystallization 

of other granitic rocks, especially those formed from magmas of relatively 

high viscosity. It results in end-stage attachment of numerous rareelement ions to the crystal surfaces of common silicate minerals. The 

binding is relatively weak, and these ions are readily mobilized if the host 

granites are altered or weathered. Despite their low concentrations, 

enormous quantities of rare elements might thus be leached from a single 

large body of granitic rock. Author's abstract

37 Jeffreys, Harold, 1936, On the radioactivities of rocks: Gerlands Beitr. 

Geophysik, Band 47, p. 149-171.

This is a statistical summary and discussion of work done on the radio-
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 223

activity of igneous rocks up to the time of the writing of the paper. The 

radium content is given for samples of granites, granodiorites, granitites, 

hornblende granites, quartz trachytes, diorites, andesites, dacites, basalts, 

dolerites, diabases, norites, gabbros, plateau basalts, eclogites, peridotites, 

and dunites from many parts of the world. The data were compiled from 

published references.

It seems that the random error of observation is of minor importance 

and that most of the variation is between the rocks themselves. The 

regional variation of radioactivity is small for the same rock type.

The author suggests that plateau basalt may be the common parent of 

granite and basalt. The statistics presented confirm the general rule that 

increasing acidity is associated with increasing radioactivity. The 

tendency of radioactive elements to concentrate in the residual portion of 

magma would explain the higher radioactivity of the granitic rocks.

38 Johnson, D. H., 1951, Reconnaissance of radioactive rocks of Massachusetts: U. S. Geol. Survey TEI-69, 17 p., issued by U. S. Atomic 

Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

A radiometric reconnaissance using car-mounted Geiger-counter equipment was made along many of the roads in Massachusetts. A northtrending belt of rocks in the south-central part of the State was found 

to be abnormally radioactive. The schists, granites, and glacial material 

that constitute this belt had a uniformly distributed, average radioactivity 

of about 0.003 percent equivalent uranium, a uranium content of less 

than 0.001 percent, and a thorium content as high as 0.032 percent. 

The radioactivity is not confined to former sedimentary rocks (that is, 

schist) nor is it associated exclusively with any igneous rock. Most of 

the radioactivity is probably due to thorium.

Pegmatite layers in gneiss near Southbridge are the most radioactive 

rocks found within the central belt. A channel sample across one of the 

pegmatite bands contained 0.011 percent equivalent uranium, 0.030 percent ThC>2 and only minor amounts of uranium. The radioactivity of the 

gneiss is consistently low.

The highest radioactivity noted in rocks outside the central belt is in 

a road cut on Highway U. S. 20 south of Worcester. A channel sample 

across one of the pegmatite layers in schist and gneiss contained 0.011 

percent equivalent uranium, 0.001 percent uranium, and 0.032 percent 

Th(>2. The radioactivity in the pegmatite seems to increase in the areas 

of sulfide minerals. Neither the adjacent gneiss nor the schist is 

appreciably radioactive.

Descriptions and analyses for uranium and thorium are given for 

samples of the Quincy and Ayer granites.

39 Joly, John, 1909, Radioactivity and geology: London, Archibald Constable 

& Co., Ltd., 287 p. See p. 35-45, 64-69.

The author presents an account of the influence of radioactive energy 

on terrestrial history. He discusses the foundations of the science of 

radioactivity, the principles underlying the measurement of radium in 

terrestrial materials, the radium in the earth's surface materials, underground temperature and radioactivity, the instability of the earth's crust 

and the ocean floor, the relation of radioactivity to mountain structure 

and the interior of the earth, the radioactivity in the exterior parts of
224 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

the earth and in the atmosphere, uranium and the age of the earth, and 

methods of radium analyses.

The mean radium content of igneous rocks is given as 4.2X10~12 

grams of radium per gram of rock. Studies of pleochroic halos in minerals of certain rocks (for example, biotite in granite) indicate that the 

halos are cuased by the radioactivity of minute inclusions of zircon and, 

more rarely, apatite.

40 Joly, John, 1930, The surface history of the earth: Oxford, England, Clarendon Press, 2d ed., 211 p. See p. 186.

The author states that the surface history of the earth dealt with in 

this volume is based directly on two recent advances in knowledge of the 

earth's crust, namely, radioactivity of rocks and isostasy. The nature 

and influence of both are explained. The author also reviews much of 

his own and other work on the radioactivity of rocks through 1929.

A correction is made in the figures given in Poole's 1927 paper (reference 86) for the radium and thorium content of the Oregonian plateau 

basalts from Oregon because only 6 of the 12 samples used in the original 

study were later found to be true Oregonian basalts. The corrected 

results read:

RADIUM THORIUM

10-12g/g 10-8 g/g

Oregonian basalt (mean of 6 samples)._______ 0. 75 0. 57

The figures for the Deccan and Hebridean basalts remain unchanged.

41 Keevil, N. B., 1942, The distribution of helium and radioactivity in rocks 

II, Mineral separates from the Cape Ann granite: Am. Jour. Sci., 

v. 240, p. 13-21.

The Essex County granite at Cape Ann, Mass., and its common mineral constituents have been thoroughly studied by the helium age method. 

The granite is more radioactive than usual, probably due to active accessories associated with the femic minerals. The relative radioactivities of 

the femics, quartz and feldspar, are about 23:2:1. Author's abstract, 

in part

The radium content of this alkaline granite ranges from 18.8 to 

21.3X10-Kgperg.

42 Keevil, N. B., 1943, The distribution of helium and radioactivity in rocks 

V, Rocks and associated minerals from Quebec, Ontario, Manitoba, 

New Jersey, New England, New Brunswick, Newfoundland, Tanganyika, Finland, and Russia: Am. Jour. Sci., v. 241, p. 277-306.

Helium and radioactivity data are presented for samples of granitic 

intrusives along the eastern coast of North America. The results tabulated include values for helium (X 10~5 cc per g), radium (X 10~1S g per g), 

thorium (X10~6 g per g), radioactivity (alphas per mg per hr). Radium 

and thorium analyses are given only for some samples.

The radioactivity of a sample of the Fitchburg granite, from the Rollstone quarry, Fitchburg, Mass., is 2.63 alphas per mg per hr. Its minerals 

have the following activity (alphas per mg per hr): Quartz, 0.1; feldspar, 

0.4; and tourmaline, 0.8.
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 225

A sample of migmatite in the Chelmsford granite from the Fletcher 

quarry, North Chelmsford, Mass., had an activity of 7.82 alphas per mg 

per hr. A sample of pegmatite (for the most part feldspar) from the quarry 

had an activity of only 0.78 alpha per mg per hr.

A radioactivity of 1.89 alphas per mg per hr was detected in a sample of 

the Quincy granite (a riebeckite granite) from the Swingle quarry, Quincy, 

Mass. The alpha activity of some of the constituent minerals is as follows: Quartz, 0.93; feldspar, 0.98; cognate xenolith, 3.45; and riebeckite 

and aegirite, 4.07. There is appreciable radioactivity in other minerals, 

probably minor accessories, that were not analyzed.

Cape Ann granite (an alkali granite) from the Johnson quarry, Cape 

Ann, Mass., had an activity of 3.35 alphas per mg per hr. Alpha activity 

of the minerals is as follows: Feldspar, 0.78; quartz, 1.34; and mafics, 10.8.

The average activity of three samples of biotite granite from a quarry 

near Franklin, Maine, was 2.14 alphas per mg per hr.

The younger rocks are generally more radioactive than the older rocks, 

and show a greater contrast in activity between their mafic and felsic 

portions than the older rocks. The higher radioactivity of the younger 

rocks may be due to later deuteric processes such as that which caused the 

albitization of the Quincy granite.

There is a large range in the radioactivity of rocks and minerals from 

Franklin and Sterling Hill, Sussex County, N. J., the highest being 10.5 

alphas per mg per hr in the mafic portion of a Precambrian basic pegmatite and the lowest being 0.00 in some of the minerals.

The alpha activity of the minerals from the rocks examined varies widely. 

Amphibole is about as radioactive as biotite and magnetite, pyroxene is 

generally less radioactive, and the feldspar and quartz are the least 

radioactive. The mafic constituents are probably about three times as 

radioactive as the felsic. The contrast between the radioactivity of the 

mafic and felsic fractions of a rock tends to be greater, the higher the 

radioactivity of the rock as a whole. The authors conclude that the radioactive elements are not distributed uniformly throughout the rocks, and 

that much of the radioactivity may be concentrated in the minor accessory 

minerals, such as apatite and zircon.

43 Keevil, N. B., 1943, Helium indexes for several minerals and rocks: Am. 

Jour. Sci., v. 241, p. 680-693.

The paper is concerned mainly with the helium index and age of several 

rocks and minerals.

The following rock and mineral specimens were investigated: Silicates, 

oxides, carbonates, and a sulphate, a borate, and a phosphate from Franklin and Sterling Hill, Sussex County, N. J.: magnetite from Port Henry, 

N. Y., and Magnet Cove, Ark.; garnet crystals from Hot Springs, Ark., 

and Wrangel, Alaska; diabases and basic rocks from Yellowstone National 

Park (Wyo.), Michigan, and New Jersey; and rhyolite and basalt from 

North Attleboro, Mass.

The radioactivity of these rocks and minerals is expressed in terms of the 

alphas per milligram per hour. Radium (X10~13 g per g) and thorium 

(X10~* g per g) contents are given only for the diabases, basic rocks, 

rhyolite, and basalt. 

459423 58 4
226 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

44 Keevil, N. B., 1944, Thorium-uranium ratios in rocks and minerals: Am. 

Jour. Sci., v. 242, p. 309-321.

The uranium content (calculated from the radium content), thorium 

content, and the thorium-uranium ratio are given for one hundred samples 

of igneous rocks and minerals, mostly from the United States and Canada. 

A Th/U ratio of 3.2 is indicated for mafic, felsic, and intermediate rocks, 

but a regional grouping of the results suggests that the value may be as 

high as 3.5.

45 Keevil, N. B., 1950, Radioactivity and mineral deposits: Am. Mineralogist, 

v. 35, p. 816-833.

The article discusses the applications of radioactivity data to the solution 

of various problems in geology, such as geologic age and the location of 

mineral deposits.

The radioactivity (in alphas per mg per hr) of rocks and minerals from 

Franklin and Sterling Hill, Sussex County, N. J., is summarized. (The 

radioactivity data are taken from reference 43). The radioactivity is 

fairly characteristic of the rock types represented. The Precambrian 

gneiss has a low activity which, the author notes, is consistent with its age. 

Pegmatitic minerals were found to be the most radioactive. Such results 

are not unexpected as radioactive elements are known to be concentrated 

in the later pegmatitic stages of differentiation of granitic magmas. The 

purest crystals of minerals have the lowest activity, whereas complex 

aggregates tend to be more highly radioactive.

Results of radioactivity determinations (alphas per mg per hr) of'ore 

and country rock are summarized for the following mining districts: Coeur 

d'Alene, Idaho, Oilman, Colo., Superior, Ariz., and Austinville, Va.

46 Keevil, N. B., Keevil, A. R., Ingham, W. N., and Crombie, G. P., 1943, 

Causes of variations in radioactivity data: Am. Jour. Sci., v. 241, 

p. 345-365.

Because of the geochemical and geothermal importance of radioactivity 

data, a report is made of recent observations on the variations in the 

radioactivity of rocks. Variations by a factor of fifty or more are sometimes found in the radioactive content from specimen to specimen. The 

greatest differences occur in certain granitic rocks, the least in some 

sedimentary sections. Regional variations are not so pronounced, but 

relatively highly radioactive provinces are indicated in Colorado and Great 

Slave-Great Bear Lake areas and relatively barren areas in parts of Ontario 

and Quebec. Some laws governing the distribution of radioactive elements 

are indicated by the discovery that the radioactive elements are more 

concentrated near the border than at the core of the Bourlamaque batholith 

[Canada], and by additional evidence of a relationship between radioactivity and proportion of accessory minerals, chiefly apatite and zircon. 

Variations in the radioactivity of granitic rocks, at least, may be due 

entirely to differences in the amounts of such minerals in which radioactive 

elements are concentrated. The need for more radioactivity data is 

emphasized. Authors' abstract

Radioactivity (alphas per mg per hr) is reported for the following: 

Diabase from the Palisades of New York and New Jersey; alkali riebeckite 

granite from Quincy, Mass.; average of granitic, other acidic, intermediate, 

and basic rocks from Maine, New Jersey, New York, Pennsylvania, North
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 227

Carolina, Tennessee, Virginia, Yellowstone Park (Wyo.), California, 

Nevada, Michigan, and Wisconsin.

47 Keevil, N. B., Larsen, E. S., Jr., and Wank, F. J., 1944, The distribution of 

helium and radioactivity in rocks VI, The Ayer granite-migmatite 

at Chelmsford, Mass.: Am. Jour. Sci., v. 242, p. 344-353.

Granite migmatite, taken from the Fletcher quarry at Chelmsford, Mass., 

has a radium content of 53X10~13 g per g. The rock is believed to have 

been formed by granitization of earlier sediments and schists.

Radioactivity data (alphas per mg per hr) are given for samples of the 

Chelmsford granitic rocks and associated minerals. Half the radioactivity 

is due to accessory minerals; and zircon, apatite, epidote, and biotite have 

more than five times the radioactivity of the parent rock. The fact that 

all the radioactive minerals in the granite migmatite were formed during 

the late hydrothermal stage of granitization suggests that the late hydrothermal fluids were relatively highly radioactive. The zircons present 

have a higher radioactivity than any other zircons from granitic rocks 

tested to date.

48 Lane, A. C., 1933, Age of the Fitchburg granite: Science, v. 78, p. 435.

A microchemical analysis is given of a sample of uraninite from a granite 

quarry at Fitchburg, Mass. The uranium content of the uraninite is 

50.20 percent.

49 Lane, A. C., and Urry, W. D., 1935, Ages by the helium method I, 

Keweenawan: Geol. Soc. America Bull., v. 46, p. 1101-1120.

The paper is mainly a discussion of the results of a detailed application 

of the helium-age method to a suite of rocks taken at widely distributed 

points within a single horizon. A suite of basalts from the Keweenawan flows 

of upper Michigan was studied. The helium, radium, and thorium contents of 25 samples are presented in tabular form. The radium content 

of the samples ranges from 0.74 to 7.23 units (radium X 10~IS g per g). 

Exact locations of the samples are given, but there are no geologic or 

petrographic descriptions. Approximately the same group of samples are 

described in reference 101.

50 Larsen, E. S., Jr., 1954, Distribution of uranium in igneous complexes, 

in Geologic investigations of radioactive deposits Semiannual progress report, June 1 to Nov. 30, 1954: U. S. Geol. Survey TEI-490, p. 

255-261, issued by U. S. Atomic Energy Comm. Tech. Inf. Service 

Ext., Oak Ridge, Tenn.

The uranium content is given for rocks and minerals from the following 

igneous suites: Modoc lavas, California; Boulder batholith, Montana; 

Highwood and Bearpaw Mountains, Mont.; Sierra Nevada, Bishop, Calif. ; 

alkalic rocks, Sussex County, N. J.; and the Idaho batholith.

The uranium content of samples from the Boulder Creek batholith, 

Colorado, is higher in the more mafic rocks and low in the most silicic 

rocks. Rocks of the western border facies have as much as ten times the 

uranium content of other rocks of the batholith.

Results of a study of the red and green phases of the Conway granite, 

New Hampshire, indicate that the red phase has a consistently higher 

uranium content and radioactivity than the green phase. Weathered 

rock has a higher radioactivity than fresh rock.
228 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

51 Larsen, E. S., Jr., and Keevil, N. B., 1942, The distribution of helium 

and radioactivity in rocks III, Radioactivity and petrology of some 

California instrusives: Am. Jour. Sci., v. 240, p. 204-215.

Radioactivity measurements (radium and thorium content and alpha 

activity) were made on samples and mineral separates of the Lakeview 

tonalite, Bonsall tonalite, and Riverside granodiorite from the southern 

California batholith. The rocks are about one-third as radioactive as 

average granitic rocks. Inclusions of small grains of apatite, zircon, and 

sphene, which are highly radioactive, probably account for nearly all the 

radioactivity of the common rock minerals.

52 Larsen, E. S., Jr., and Keevil, N. B., 1947, Radioactivity of the rocks of 

the batholith of southern California: Geol. Soc. America Bull., v. 58, 

p. 483-493.

Determination of radioactivity has been made on 43 rocks, carefully 

selected from the different mapped units of the complex Cretaceous batholith of southern California; they range from gabbro to granite. The 

activity of the gabbro averages about 0.3 alphas per mg per hr, that of 

the tonalites, 0.8, the granodiorite 1.3, and the granites over 2.0. The 

activity of the average rock of the batholith is about 0.9 alphas per mg 

per hr. Most of the rocks have been analyzed, and modal compositions 

are given. The radioactivity and the percentages of K2O, SiC>2, and PbO 

are plotted on a variation diagram. The variation curve for activity 

nearly parallels that for K2O, and the ratio of activity to K2O is about 

0.5. The radioactivities of some rocks fall far from the variation curve, 

and degree of activity correlates with K2O content. A less-marked correlation between activity SiO2 and PbO was also noted. The K2O, SiO2, 

PbO, and radioactivity concentrate in the residual liquid during crystallization and differentiation. PbO follows K2O closely, as it is concentrated in the K2O minerals, but radioactivity is very low in the K2O 

minerals and is greatly concentrated in the accessory minerals. Authors' 

abstract

53 Larsen, E. S., Jr., Keevil, N. B., and Harrison, H. C., 1952, Method for 

determining the age of igneous rocks using the accessory minerals: 

Geol. Soc. America Bull., v. 63, p. 1045-1052.

The article is mainly a discussion of the method of determining the age 

of igneous rocks using the accessory minerals. The radioactivity (in 

alphas per mg per hr) is given for samples of the following minerals: Zircon 

from Oklahoma, Statesville, N. C., New Hampshire, the southern California batholith, and the Snoqualmie batholith, Washington; sphene from 

Vermont marble and the southern California batholith; and apatite from 

the southern California batholith and the Snoqualmie batholith, Washington.

54 Larsen, E. S., Jr., and Phair, George, 1954, The distribution of uranium and 

thorium in igneous rocks, in Faul, Henry, ed., Nuclear geology, p. 

75-89: New York, John Wiley & Sons Inc., 414 p.

This article describes the present state of progress in the study of the 

distribution of uranium and thorium in igneous rocks.
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 229

The range and (or) average of the uranium content of igneous rock types 

in North America is summarized as follows:

Uranium 

Rock type (ppm)

Stony meteorites..______________________ 0.35-1.0

Ultramafic rocks________________________ .3

Gabbroic rocks___________________ .94-.96±0.11 

Intermediate rocks________________ 1.4±.2-3.03 

Granitic rocks..___________________ 2.77-4.02

Preliminary evidence suggests that volcanic and hypabyssal rocks have a 

higher average radioactivity and uranium content than do plutonic rocks of 

similar composition.

As much as 40 percent of the uranium in fresh-appearing rocks is readily 

leachable. The distribution of leachable radioactivity is not completely 

known but may occur: "(1) in metamict phases of primary silicates, (2) 

as interstitial material derived from late-magmatic, deuteric, or hydrothermal solutions, (3) in certain nonmetamict partly soluble radioactive 

accessories, such as apatite, and (4) as adsorbed ions in disseminated 

weathering products, such as iron oxide."

Results of a study of the distribution of uranium and radioactivity in 

rocks of the southern California batholith show that, generally, rocks rich, 

in Mg, Fe, and Ca and poor in silica and alkalis tend to be poor in radioactive elements. Thus the radioactivity would be low in the dark gabbros, 

moderate in the diorites, and highest in the silica-rich rocks.

Much of the radioactivity in igneous rocks is concentrated in zircon, 

sphene, and apatite. The uranium content in parts per million is given for 

the common rock-forming minerals and radioactive accessory minerals of 

the Woodson granodiorite, California batholith; the Rattlesnake granite, 

California batholith (calc-alkalic granite); and the Conway granite, New 

Hampshire (a sodic granite).

Acid rocks generally have a higher concentration of radioactive elements 

than basic rocks, although there are exceptions. For example, lamprophyric dike rocks may contain large amounts of uranium inconsistent with 

their low silica content. Calc-alkaline granites commonly contain less 

uranium than the alkali granites and syenites tested to date. The 

authors feel that "perhaps the safest generalization that can be made at 

this time is that the maximum concentration of uranium and thorium is 

found in the youngest member of a series, regardless of the particular liquid 

line of descent that the magma may have followed/'

55 Larsen, E. S., Jr., Phair, George, Gottfried, David, and Smith, W. L., 

1956, Uranium in magmatic differentiation: Internat. Conf. on 

Peaceful Uses of Atomic Energy, Geneva 1955, Proc., v. 6, Geology of uranium and thorium, p. 240-247; U. S. Geol. Survey Prof. 

Paper 300, p. 65-74.

"The results reported here indicate that the change in uranium content 

of the successive members of any one magma series is less systematic than 

is the change in major oxides. How much of this variability is real 

growing out of the diverse paths open to trace elements during magmatic 

differentiation and how much is apparent inherent in the traditional 

methods of sampling igneous rocks remains to be determined. The
230 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

most variable rocks are those of intermediate composition; there is little 

or no overlap between the uranium contents of the gabbroic and granitic 

extremes in any one magma series. Even in the least favorable instances 

it is generally possible to define a trend by assembling uranium data on a 

relatively large number of samples. In all those series studied in which 

fractional crystallization may be assumed to have been the major factor 

in differentiation the trends are similar: uranium is enriched in the youngest 

rocks, these being generally high in SiC>2 and E^O and low in CaO and MgO. 

The maximum enrichment (>20 ppm) is found in extreme differentiates 

very poor in CaO. More data are needed on those series in which 

processes other than fractional crystallization are believed to have played 

important roles. In such rocks the uranium content developed may 

depend upon local geological conditions."

Uranium contents are listed for the following igneous rock suites: 

Southern California batholith, Sierra Nevada batholith, Idaho batholith, 

Bearpaw and Highwood Mountains of Montana, San Juan lava series of 

western Colorado, Modoc lava series of northern California, Conway 

(N. H.) granite, and the Boulder Creek batholith, Colorado.

Results of leaching experiments indicate that leachable uranium is 

coated on the surface of mineral grains, and therefore deposited in the 

late stages of magmatic differentiation. The results of leaching experiments on samples of coarse granite show that "most of the uranium 

associated with the common rock-forming minerals is leachable and that 

such uranium is released by removal of relatively small amounts of the 

mineral." Authors' summary, in part

56 Larsen, E. S., Jr., Waring, C. L., and Berman, Joseph, 1953, Zoned zircon 

from Oklahoma: Am. Mineralogist, v. 38, p. 1118-1125.

This article is mainly a mineralogic description of zoned zircons from 

a pegmatite body cutting the Quanah granite in the Wichita Mountains of 

Oklahoma. The crystals have recurrent zones of fresh and metamict 

zircon. Chemical and spectrographic analyses of the various zones in 

the zircon are given. The uranium content was determined by the 

fluorimetric method. A sample of fresh zircon contained 0.013 percent 

uranium, whereas two samples of metamict zircon contained 0.117 and 

0.165 percent uranium, respectively.

57 Love, J. D., 1954, Pinedale area, in Geologic investigations of radioactive 

deposits Semiannual progress report, June 1 to Nov. 30, 1954: 

U. S. Geol. Survey TEI-490, p. 230, issued by U. S. Atomic Energy 

Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

"Extensive masses of Precambrian granite in the vicinity of Fremont 

Butte, on the southwest flank of the Wind River Mountains, show radioactivity that is several times background." One sample of radioactive 

granite from this area contained 0.015 percent equivalent uranium and 

0.002 percent uranium; another sample contained 0.030 percent equivalent 

uranium and 0.002 percent uranium.

58 McKeown, F. A., 1951, Reconnaissance of radioactive rocks of Vermont, 

New Hampshire, Connecticut, Rhode Island, and southeastern New 

York: U. S. Geol. Survey TEI-67, 46 p., issued by U. S. Atomic 

Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

Traverses using car-mounted Geiger-counter equipment were made of
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 231

rocks in Vermont, Connecticut, Rhode Island, New Hampshire, and 

southeastern New York.

Rocks of the Grenville series, metamorphic rocks of sedimentary 

origin, and many granitic intrusives characterize the Hudson and Housatonic Highlands of southeastern New York and western Connecticut. The 

radioactivity of the Grenville rocks ranges from 0.001 to 0.240 percent 

equivalent uranium, with a maximum uranium content of 0.095 percent. 

The maximum radioactivity observed in the metamorphic rocks was 

0.013 percent equivalent uranium, and that in the granite was 0.006 percent 

equivalent uranium. The most radioactive deposits are in pegmatites. 

Analyses of samples from the area show that most of the radioactivity 

is due to thorium-bearing minerals.

The bedrocks of the Bear Mountain area within the Highlands, N. Y., 

are pegmatite, gneiss, schist, and gneissic granite. Mineral analysis of 

a quartz-feldspar pegmatitic gneiss near Hessian Lake showed that it 

contains abundant zircon, lesser amounts of opaque minerals, and an 

unidentified uranium-bearing mineral or aggregate of minerals coating 

various grains of the pegmatite with a dull yellowish crust. Samples of 

the uranium mineral contain 0.004 to 0.065 percent uranium. The zircon 

also is radioactive. Near Highland Falls, N. Y., dark-gray quartzf eldspar-biotite gneiss is interbanded with lesser amounts of pinkish quartzfeldspar-biotite gneiss. Quartz-feldspar-biotite pegmatite masses and 

lenses are distributed irregularly throughout the gneiss. The pegmatite 

is the most radioactive rock in the area, containing 0.002 to 0.057 percent 

equivalent uranium and 0.001 to 0.005 percent uranium. The rocks south 

of Hessian Lake, and west of Camp Smith, N. Y. are massive fine-grained 

quartz-feldspar-biotite gneisses, probably in the Storm King granite. 

Radioactivity is limited to a few massive layers (3 to 5 feet thick) that contain 0.006 to 0.013 percent equivalent uranium and 0.003 to 0.005 percent 

uranium. The radioactive elements are believed to be syngenetic with the 

enclosing metasedimentary rocks.

A belt of abnormally radioactive rocks extends from western Rhode 

Island and eastern and central Connecticut through central Massachusetts 

into eastern Vermont and western and northern New Hampshire. The 

rocks have a low uranium content (a maximum of 0.001 percent uranium), 

and the radioactivity is due mainly to thorium. Pegmatites have a 

radioactivity comparable to the surrounding rocks. That part of the belt 

in Massachusetts is described in reference 38.

Analyses of many samples for equivalent uranium and uranium are 

presented in tabular form.

59 McKeown, F. A., and Klemic, Harry, 1953, Reconnaissance for radioactive 

materials in northeastern United States during 1952: U. S. Geol. 

Survey TEI-317A, 66 p., issued by U. S. Atomic Energy Comm. Tech. 

Inf. Service Ext., Oak Ridge, Tenn.

The authors examined iron ore deposits and associated rocks in the 

Adirondack Mountains of New York and in the Highlands of New Jersey.

The large low-grade magnetite ore body at the Benson mines, St. Lawrence County, N. Y., is a replacement body of magnetite and hematite in 

microcline granite gneiss. Garnet-rich zones are the most radioactive parts 

of the ore body. Field tests and analyses for radioactivity indicate that the 

rock and ore contain from 0.002 to 0.006 percent equivalent uranium with 

an average of 0.005 percent equivalent uranium. Torbernite has been re-
232 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

ported from pegmatite in the northwestern part of the mine. The outcrop 

of pegmatite had been stripped away at the time this examination was 

made, but several pieces of it in the waste rock contained allanite.

Magnetite ore at the Rutgers mine, Clinton County, N. Y., is in pink 

syenite gneiss and plagioclase syenite gneiss of the Lyon Mountain granite 

gneiss, which contain numerous schlieren of pyroxene skarn. The ore 

contains from 0.005 to 0.010 percent equivalent uranium, and the gneiss 

and schlieren contain less than 0.002 percent equivalent uranium. The 

radioactive minerals of the ore are apatite and zircon. The authors infer 

that the radioactive elements are disseminated through the ore body and 

are not concentrated locally.

The Mineville group of magnetite mines is in the Mineville district, 

near Mineville, Essex County, N. Y. The Miller, Old Bed, and "21"- 

Bonanza-Joker are three faulted parts of one complexly folded ore bed in 

the Mineville group. The ore is massive and granular; apatite is a constituent of the gangue in rich as well as lean ore. Granular high-grade ore 

generally contains the least amount of apatite and other gangue minerals. 

Medium- to fine-grained ore (magnetite grains less than about 2 millimeters across) contains radioactive fluorapatite-rich layers and stringers as 

well as disseminated fluorapatite. Chemical analysis of a sample of handpicked apatite grains shows a uranium content of 0.018 percent. The 

amount of radioactivity of various samples (ore, rock, etc.) seems to be a 

function of the amount, as estimated visually, of red- or flesh-colored 

apatite in the sample.

At the Canfield phosphate mine, Morris County, N. J., the ore is a 

granular aggregate of magnetite and greenish-gray apatite; quartz, feldspar, and biotite are minor constituents. Among the rocks on the dump, 

those with the highest apatite content are also the most radioactive. 

Monazite is also present in small amounts and is radioactive.

Anomalous radioactivity was noted within the Pickering gneiss and at 

or near the contact of the gneiss with the Franklin limestone, in the Chestnut 

Hill-Marble Mountain area (Northampton County, Pa., and Warren 

County, N. J.). The contact between the gneiss and limestone has been 

injected with pegmatite in some places. Thin coatings of autunite(?) 

were found on slickensided surfaces and on joints in serpentine in the 

Williams quarry. A phlogopite-rich zone along the west side of the quarry 

is also radioactive. The most radioactive rock in the Marble Mountain 

area is an aphanitic rhyolitelike-quartz sericite schist, samples of which 

contain as much as 0.044 percent equivalent uranium and 0.005 percent 

uranium. The radioactive elements were probably derived from pegmatite, 

and their concentration controlled by structure and lithology.

Analyses for uranium of samples from other magnetite-apatite mines and 

prospects, which are not significant as possible sources of radioactive elements, are presented in tabular form.

60 Marble, J. P., 1935, Age of allanite from Amherst County, Virginia, 

U. S. A.: Am. Jour. Sci., 5th ser., v. 30, p. 349-352.

Three samples of fresh allanite from a pegmatite in hypersthene granodiorite in Amherst County, Va., contain an average of 0.083 percent 

uranium. A weathered part of the allanite contains 0.031 percent 

uranium.
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 233

61 Marble, J. P., 1940, Allanite from Baringer Hill, Llano County, Texas: 

Am. Mineralogist, v. 25, p. 168-173.

A sample of allanite from pegmatite at Baringer Hill, Llano County, 

Tex., contains 0.033 percent uranium. An autoradiograph demonstrates 

that the radioactive elements in the mineral are sparse and uniformly 

distributed. Petrographic studies show that the mineral has become 

isotropic and is metamict. A chemical analysis of the mineral is given.

62 Marble, J. P., 1943, Possible age of allanite from Whiteface Mountain, 

Essex County, New York: Am. Jour. Sci., v. 241, p. 32-42.

This article is mainly a study of the use of allanite for "age-index" 

purposes.

Allanite crystals in granitic pegmatite were collected from several 

localities at Whiteface Mountain, Essex County, N. Y. Crushed, gneissic 

anorthosite containing as much as 5 percent of dark minerals is the host 

rock. The pegmatite is comprised of microcline, plagioclase, and hypersthene and accessory magnetite and allanite. There is some quartz and 

locally minor biotite or phlogopite. The potassium feldspar has a slight 

radiating tendency and a deeper pink color around the allanite crystals.

Microscopic examination of fragments of the allanite revealed that the 

mineral is anisotropic and strongly pleochroic, which indicates freshness 

and absence of alteration. Autoradiographs of the allanite show a generally 

uniform distribution of the radioactive elements. Five samples of the 

allanite contain an average of 0.069 percent uranium. A chemical analysis 

of the mineral is also given.

The author analyzed a sample of allanite from pegmatites in the nontitaniferous magnetites near Mineville, Essex County, N. Y. Three 

samples of this mineral contain an average of 0.0086 percent uranium. A 

chemical analysis of the mineral is given. The large water content and 

nearly complete optical isotropy of the mineral indicate a change to the 

metamict state with consequent alteration.

63 Marble, J. P., 1950, Lead-uranium ratio and possible geologic age of 

allanite from Greenwich, Massachusetts: Am. Mineralogist, v. 35, 

p. 845-852.

Anisotropic allanite from a pegmatitic lens in the Monson granodiorite 

at Greenwich, Mass., contains 0.095 percent uranium. A chemical 

analysis and optical and mineralogic descriptions of the allanite are given. 

The article is mainly a discussion of the lead-uranium ratio and possible 

age of the mineral.

This locality is now flooded by the Quabbin Reservoir.

64 Morgan, J. H., and Auer, M. L., 1941, Optical, spectrographic, and 

radioactivity studies of zircon: Am. Jour. Sci., v. 239, p. 305-311.

The three varieties of zircon in granites of the Lake Superior region are the 

Keweenawan or normal, hyacinth, and malacon. They are distinguished 

by their optical characteristics, color, and crystal form. The normal 

variety has a low radioactivity, the highest optical indices, and the strongest birefringence. The hyacinth variety has a higher radioactivity, lower 

optical indices, and weaker birefringence than the normal type. The 

malacon variety has the highest radioactivity, the lowest optical indices, 

and the weakest birefringence of the three varieties. The radioactivity was 

measured with a Geiger counter.
234 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

The results of spectrographic analyses of 24 samples of zircon show no 

apparent relationship between yttrium content and radioactivity, nor 

between yttrium content and hafnium content.

The type of zircon present in a granite may depend on the amount of 

uranium available at the time of crystallization of the zircon. "This may 

imply that the concentration of uranium is greater in some magmas than in 

others, and may sometimes be indicative of concentration of uranium in 

the late stages of magmatic intrusion.

"The concentration of uranium in granite magmas of one intrusive 

period may be similar over wide areas, since granite intrusives of similar 

time relationships can be distinguished by the zircon variety present in 

them. Such similarity in concentration of uranium may mean a common, 

deep-seated source for the magma."

65 Moxham, R. M., and Nelson, A. E., 1952, Radioactive pegmatite minerals 

in the Willow Creek mining district [Alaska]: U. S. Geol. Survey Giro. 

184, pt. 2, p. 7-10.

Samples from 11 pegmatites in the Fishhook Creek-Archangel Creek 

area in the Willow Creek mining district, Alaska, have an average of 0.004 

percent equivalent uranium. The pegmatites, intruded into schist and 

quartz monzonite, probably represent end phases in the consolidation of the 

Talkeetna batholith. The radioactivity of the pegmatites is due to one 

or more of the following minerals: Uraninite, thorite, cyrtolite, and allanite. The greatest concentration of these minerals is found in association 

with biotite.

Six analyses of heavy-mineral separates of the pegmatites average 0.034 

percent uranium.

66 Moxham, R. M., and West, W. S., 1953, Radioactivity investigations in 

the Serpentine-Kougarok area, Seward Peninsula, Alaska, 1946: 

U. S. Geol. Survey Circ. 265,11 p.

Radioactive minerals in small quantities were found in the bedrock and 

alluvium within the outcrop area of granite at the head of Serpentine River.

Tests of radioactivity at outcrops of the granite indicate that small 

amounts of radioactive material is disseminated .throughout the mass. 

Four variants of the normal granite have been recognized: early and late 

differentiates, and pegmatitic and fine-grained facies. All variants except 

the early differentiates show radioactivity in excess of the normal granite. 

The average equivalent uranium content of 29 samples of the granitic 

variants is 0.008 percent. The heavy-mineral portions of these samples 

average 0.034 percent equivalent uranium.

The radioactivity of the placer material and bedrock is attributable to 

zircon, sphene, allanite, hydrogoethite, and two unidentified secondary 

minerals. Neither the bedrock nor placer deposits contain sufficient 

radioactive materials to be of present commercial interest. Authors' 

abstract

67 Muench, O. B., 1931, The analysis of cyrtolite for lead and uranium: Am. 

Jour. Sci., 5th ser., v. 21, p. 350-357.

A sample of hafnium-rich cyrtolite from a pegmatite dike at Bedford, 

N. Y., was found to contain 7.29 percent uranium. The chemical method 

used for the determination of uranium is described in detail. The analysis 

(plus one for lead) was made for age-determination studies.
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 235

68 Muench, O. B., 1934, The analysis of Bedford cyrtolite for lead and uranium: Am. Chem. Soc. Jour., v. 56, p. 1536.

A specimen of cyrtolite from the same pegmatite as that described in 

reference 67, at Bedford, N. Y., was analyzed for lead and uranium to 

determine whether or not different specimens of minerals from the same 

pegmatite dike might give different ages due to a reopening of the dike 

from time to time. The average uranium content of 5 samples of this 

cyrtolite is 6.73 percent. "The lead-uranium ratio is practically the same 

as was obtained by the earlier determination (0.051). [Reference 67.] 

The result indicates that the material is uniform in age and does not favor 

the possibility that the dike has been reopened and material intruded."

69 Muench, O. B., 1950, Recent analyses for age by lead ratios: Geol. Soc. 

America Bull., v. 61, p. 129-132.

This article is mainly a discussion of the determination by the leaduranium ratio of the age of a sample of monazite and euxenite from 

pegmatite. The results of analyses for uranium are given as follows:

Average

percent Number of 

Mineral Location uranium samples

Monazite______ Bull Creek, near Las Vegas, 0. 122 1

N. Mex. 

Euxenite______ Trout Creek Pass, Colo____ 3.41 1

70 Narten, P. F., and McKeown, F. A., 1952, Reconnaissance of radioactive 

rocks of the Hudson Valley and Adirondack Mountains, New York: 

U. S. Geol. Survey TEI-70, 54 p., issued by U. S. Atomic Energy 

Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

A radiometric reconnaissance using car-mounted Geiger-counter equipment was made of the Paleozoic rocks of the Hudson Valley and the 

Precambrian rocks of the Adirondack Mountains in New York State. 

The log of localities examined and analytical data are presented in tabular 

form. Some of the more radioactive rocks are described in detail. Those 

mentioned below are only those not discussed in reference 58.

The most radioactive material on the dump of an active talc mine 

southwest of Edwards is a coarsely crystalline pegmatite. The highest 

radioactivity is associated with a black material scattered through the 

feldspar. A selected grab sample of this material contains 0.050 percent 

equivalent uranium, 0.043 percent uranium, and 0.02 percent ThC>2. 

Trace amounts of allanite and uraninite are present.

Abnormally radioactive biotite granite-gneiss lenses were found in 

fine-grained mafic rock about 7 miles south of De Peyster. A grab sample 

of one of the more radioactive lenses contains 0.007 percent equivalent 

uranium and 0.002 percent uranium. Trace amounts of zircon and 

monazite are present, and their thorium content probably accounts for 

most of the radioactivity of the rock.

North of the town of Lake George, a dark-gray pegmatitic zone in 

gabbro, the latter intrusive into syenite, is radioactive, A grab sample of 

the pegmatite contains 0.024 percent equivalent uranium, 0.013 percent 

uranium, and 0.03 percent ThO2 . A grab sample of the syenite contains 

0.004 percent equivalent uranium, 0.002 percent uranium, and 0.002 

percent ThO2 . The gabbro is estimated to contain 0.002 percent or less 

equivalent uranium.
236 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Pegmatite in gneiss about 6 miles southwest of Graphite is abnormally 

radioactive. A 3-inch zone of minerals in one of the pegmatites was the 

most radioactive. A sample from the zone contains 0.016 percent 

equivalent uranium, 0.002 percent uranium, and 0.05 percent ThOj.

The abnormal radioactivity of Precambrian rocks in the northwest 

and southeast parts of the Adirondacks is most apparent near the contacts 

of igneous and metamorphic rocks. Pegmatites, however, are the only 

known rocks in this area with concentrations of radioactive elements.

71 Nelson, J. M., and Narten, P. P., 1951, Reconnaissance of radioactive 

rocks of Maine: U. S. Geol. Survey TEI-68, 44 p., issued by U. S. 

Atomic Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

In the summer of 1948, the authors traversed the State of Maine using 

car-mounted Geiger-counter equipment. The maximum radioactivity 

noted was 0.008 percent equivalent uranium and 0.003 percent uranium. 

A log of localities estimated to contain 0.003 percent equivalent uranium 

or more, all sample localities, and field and laboratory analyses of samples 

are presented in tables.

The State was divided into two areas on the basis of radioactivity. 

Area 1 is abnormally radioactive and comprises about 1,400 square miles 

extending from Lewiston westward to New Hampshire. This area is 

one of gneiss and schist, much intruded by pegmatite. The radioactivity 

of the rocks of 128 outcrops ranged from 0.001 to 0.008 percent equivalent 

uranium with a maximum uranium content of 0.003 percent.

Area 2 comprises the remainder of the State and has low radioactivity. 

Granitic rocks of the coastal belt of rocks have a maximum equivalent 

uranium content of 0.005 percent.

Small granitic stocks are abundant in area 1, and there is an approximate correlation between the amount of radioactivity and areas where 

these stocks are most numerous. In the coastal belt of area 2, granitic 

intrusions are larger and the radioactivity is lower. The rest of area 2 

has the fewest number of granitic intrusions and the least radioactivity.

The authors suggest that the probability of finding concentrations of 

radioactive minerals is greatest in areas containing large numbers of small 

granitic intrusives. The relation might be explained by assuming that 

the additional heat generated by radioactive elements would cause an 

intrusive body to stay fluid longer and thus enable it to rise higher in the 

intruded rocks. The concentrations of radioactive elements in granitic 

rocks could be a result of magmatic differentiation, formation in place 

from rocks originally high in radioactive constituents, or a combination 

of these factors.

The most radioactive metamorphic rocks in Maine are the high-grade 

gneiss and schist in the area west of Lewiston (area 1). In contrast, the 

widespread exposures of slate in northern Maine (area 2) have the lowest 

average radioactivity of any of the rocks examined in the State.

Included with the report is a table listing the equivalent uranium, 

uranium, and in few cases thorium, contents as determined by laboratory 

analysis of 21 samples of various igneous and metamorphic rocks from 

Maine. Of the samples analyzed, 10 contain less than 0.000 percent 

uranium, 8 contain 0.001 percent uranium, 2 contain 0.002 percent 

uranium, and 1 contains 0.003 percent uranium.

The authors conclude from their data that, in Maine, the granitic 

rocks have the highest radioactivity in their respective areas, that areas
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 237

with high-grade metamorphic rocks tend to be more radioactive than 

areas with low-grade metamorphic rocks, and that the mafic rocks have 

the lowest average radioactivity.

72 Neuerburg, G. J., 1955, Occurrences of uranium in veins and igneous 

rocks, in Geologic investigations of radioactive deposits Semiannual 

progress report, Dec. 1, 1954 to May 31, 1955: U. S. Geol. Survey 

TEI-540, p. 150-152, issued by U. S. Atomic Energy Comm. Tech. 

Inf. Service Ext., Oak Ridge, Tenn.

The labile uranium contents of igneous rocks are considered to represent that part of the total uranium content that is most likely to have 

changed during the rock's history and that may, therefore, provide clues 

to the movement of uranium during the formation of ore deposits. Likewise, it is thought that Th/U ratios may provide additional information 

on the movement of uranium during a rock's history.

The leaching procedure consists of the following: 4 grams of rock, pulverized to minus 20 mesh, are leached in 800 ml of 0.05 M HNOs on a 

steam bath at a temperature of 80-85 °C for one-half hour. This procedure was adopted on the basis of experiments that showed it entailed 

virtually complete solution of pitchblende and a variety of hexavalent 

uranium minerals while dissolving less than 10 percent apatite and 

negligible amounts of the common minor accessory minerals.

Analyses of a few zeolites showed uranium contents ranging from 0.9 

ppm to 27.6 ppm. In 1937 Goldschmidt predicted that zeolites should 

not accommodate uranium in their structure. The finding of appreciable 

uranium in these zeolites may mean that it is held in cation exchange position. This is also implied by associated amygdaloidal analcite and natrolite, containing 0.05 ppm and 4.4 ppm uranium, respectively, on the 

assumption that analcite should adsorb no uranium while natrolite may 

readily adsorb it. If uranium is readily adsorbed by zeolites, surveys of 

areas containing zeolites may serve to identify volumes of rock through 

which uraniferous solutions have passed. Extracts from author's report

73 Neuerburg, G. J., 1956, Uranium in igneous rocks of the United States of 

America: Internat. Conf. on Peaceful Uses of Atomic Energy, 

Geneva 1955, Proc., v. 6, Geology of uranium and thorium, p. 231-239.

Neuerburg, G. J., 1956, Uranium in igneous rocks of the United States: 

U. S. Geol. Survey Prof. Paper 300, p. 55-64.

Uranium is an ubiquitous and exceedingly small component of all 

igneous rocks. The uranium content of igneous rocks largely reflects the 

chemistry of the rock; silicic igneous rocks generally contain more uranium 

than do the mafic igneous rocks within any given petrographic association. 

Equivalent rocks from separate petrographic associations differ in uranium 

content. The quantity of uranium also varies within seemingly homogeneous rock masses. There is uncertain evidence for a regional variation 

in uranium content of igneous rocks beyond that which can be assigned to 

petrographic character.

Uranium is distributed among six major environments in igneous rocks: 

(a) uranium minerals as such, (b) uranium disposed in the structure of the 

rock minerals by diadochy and in structural defects in crystals, (c) uranium 

held in cation exchange positions, (d) uranium in unknown form adsorbed 

on surfaces of crystals, (e) uranium dissolved in fluid inclusions within rock 

minerals, and (f) uranium dissolved in intergranular fluids.
238 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

The uranium content of these six environments varies from rock to rock, 

and each is thought to have differing geologic histories, such that the total 

uranium content of an igneous rock represents the interplay of a complex 

series of events taking place during and since crystallization of the rock. 

Thus, the total uranium contents of igneous rocks are dynamic quantities 

that cannot be referred to any single event. The uranium in the six 

environments displays differing degrees of reactivity toward and accessibility to solutions passing through the rock.

Current techniques permit crude determinations of the amounts of 

uranium in the different environments or in groups of the environments. 

Such information is of potential value to theoretical considerations and to 

prospecting for uranium ore deposits. Dilute mineral acids dissolve 

nearly all the uranium except that held structurally in the rock minerals. 

The quantity of uranium held structurally can be referred to the last 

crystallization or recrystallization of the rock minerals and is the quantity 

of prime importance to geochemical studies. The readily dissolved, or 

labile uranium of a rock is a measure of that part of the uranium content of 

a rock most likely to have been changed after final consolidation. If 

uranium aureoles exist around ore deposits, they will be measured by the 

quantity of labile uranium.

From study of fabric distribution of uranium, it is evident that the total 

uranium content of an igneous rock reflects in no way the uranium content 

of the melt from which it crystallized. The total uranium content of an 

igneous rock is the sum of (a) the amount of uranium fixed in the rock at the 

time of final consolidation, and (b) the amount of labile uranium that 

probably was changed after consolidation of the rock.

Studies of the occurrence and quantity of uranium in igneous rocks is 

important for two reasons: (a) these rocks are potential low-grade ores, 

and (b) uranium in currently minable concentrations has originated both 

directly and indirectly from igneous activity.

74 Neuerburg, G. J., and Gottfried, David, 1954, Age determinations of the 

San Gabriel anorthosite massif, California: Geol. Soc. America Bull., 

v. 65, p. 465.

The radioactivity of zircons from altered norite from the anorthosite 

massif in the San Gabriel Mountains, Calif., is 18 alphas per mg per hr 

and is the lowest value yet obtained for zircons separated from igneous 

rocks. Samples of zircon from pegmatite in the massif have a radioactivity 

of 50 alphas per mg per hr.

75 Neumann, Henrich, Mead, Judson, and Vitaliano, C. J., 1954, Trace 

element variation during fractional crystallization as calculated from 

the distribution law: Geochim. et Cosmochim. Acta, v. 6, p. 90-99.

The distribution of trace elements in rocks formed by crystallization is 

governed by (a) the laws of crystallization and (b) the laws of distribution 

of trace elements, that is, an element's diadochical properties, its ionic 

radii and chemical bonding.

The distribution law states there is a constant ratio between concentrations of any given component in any two phases of a system in equilibrium 

at constant temperature and pressure. This law is only approximate for 

essential or varietal elements, owing to widespread solid solution, but for 

trace elements (less than 1 percent) the error is negligible.
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 239

Distribution coefficients may be expressed as functions of the partial 

vapor pressure of the trace element; therefore, coefficients vary with 

changing temperature and composition of the solidifying magma.

The age relationships between different minerals in a crystallizing magma 

are equally as important as the distribution factors in considering the 

distribution of trace elements between minerals. For example, a trace 

element may have a greater distribution coefficient in mineral B than in 

mineral A, yet mineral A might contain nearly all of the trace element if it 

crystallized before mineral B and was removed from reaction in the system.

Variation with temperature may change a distribution coefficient to the 

extent that a mineral crystallizing from a magma may remove a trace 

element from that magma at high temperature, whereas at a lower temperature the magma may be enriched in the same trace element by further 

crystallization of the same mineral.

Variation of distribution coefficients with pressure is considered to be 

negligible. Thus extreme care must be used if distribution coefficients are 

determined by a study of naturally occurring rocks, and a determination 

may, in many cases, be impossible.

76 Ockerman, J. B., and Daniels, Farrington, 1954, Alpha-radioactivity of 

some rocks and common materials: Jour. Phys. Chemistry, v. 58, p. 

926-927.

The alpha activity of 300 samples of various types of materials is 

reported. The materials tested include granites, limestones, bentonites, 

building materials, well-water residues, and plant litter. Bentonite clays 

with adsorbed uranium and other alpha emitters were more radioactive 

than granites.

77 Ordway, R. J., 1951, Radioactivity of some Maine pegmatites: Maine 

State Geologist Rept., 1949-50, p. 91-106.

No commercial concentrations of uranium-bearing minerals were found 

in any of the pegmatites studied. About two-thirds of all the pegmatites 

checked with the Geiger counter were found to contain black radioactive 

mineral grains, probably uraninite in most instances. Invariably these 

black mineral grains were found to be surrounded by smoky quartz and 

(or) stained feldspar, with the dark color fading out gradually away from 

the radioactive mineral grains. Evidently the invisible rays given off by 

the radioactive material caused the quartz and feldspar to become dark 

colored. When the counter probe was moved a foot or so from these 

radioactive minerals, a normal pegmatite reading was obtained. Most of 

these uranium-bearing minerals were found in wall zones or core-margin 

zones.

Several pegmatites were found to contain certain areas which consistently 

were too radioactive for reading on the most sensitive scale of the Geiger 

counter. A sulfide vein cutting the Melrose pegmatite is representative 

of these areas. Analysis by the Trace Elements Section of the U. S. 

Geological Survey showed an equivalent uranium content of a 1-lb sample 

to be 0.09 percent very low.

An attempt was made to delineate zones in pegmatites on the basis of 

radioactivity. Potassium is feebly radioactive and is present in perthite 

which is abundant in core and core-margin zones; potassium is absent in 

the plagioclase feldspars which predominate in border and wall zones.
240 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Nearly 100 counts were made on different zones in the Red Hill pegmatites 

in Rumford with results which are summarized in figure 4. The average 

count in each zone varied from 1.5 to 2.0 times the background count the 

border zone giving the 2.0 count. These results appear not to be significant.

In every pegmatite checked with the Geiger counter, large masses of 

perthite gave readings which were about double the background count or 

slightly more, whereas large quartz crystals (not smoky) gave readings 

which were about equal to the background count or less.

Readings taken along the margins of inclusions of wall rock or along 

wall rock contacts with pegmatites were double the background count or 

more in parts of some pegmatites, but gave normal counts in other parts 

of the same pegmatites and in other pegmatites. Author's summary, in 

part

78 Page L. R., 1950, Uranium in pegmatites: Econ. Geology, v. 45, p. 12-34.

Both primary and secondary uranium minerals are common constituents 

of pegmatites, but they rarely occur in sufficient quantities to be an 

economic source of uranium. The physical properties and chemical 

composition of the more common uranium-bearing minerals in pegmatites 

are presented in tabular form.

Uranium-bearing pegmatites are made up of units of contrasting mineralogy and (or) texture. These units are classified as zones, fracture 

filling units, and replacement units. Uranium minerals are most common 

in intermediate zones and cores of pegmatites, although they may occur 

in any of the structural units. The potash-rich pegmatites are the most 

likely sources of uranium minerals, and soda-rich and lithia-rich pegmatites 

are somewhat less favorable.

This article describes some of the uranium-bearing pegmatites in the 

United States. At the Ruggles mine, in Grafton, N. H., uraninite associated with secondary alteration products occurs in part of a perthitequartz-plagioclase zone surrounding a perthite pegmatite core. Uranium 

minerals are also in quartz fracture-filling units that cut the pegmatite.

The uranium-bearing zone at the Palermo pegmatite, Groton, N. H., is 

composed mainly of plagioclase, quartz, muscovite, and perthite, and 

contains unusual amounts of beryl and rare phosphate minerals. Uraninite 

and its alteration products are the principal uranium minerals.

The Bob Ingersoll Dike 2 pegmatite in Keystone, S. Dak., contains 

uraninite and its alteration products in an irregular lens of muscovite-albite 

(cleavelandite)-quartz, which may be a replacement unit.

Microlite occurs in lepidolite-quartz-cleavelandite cores in the Brown 

Derby pegmatite (Gunnison County, Colo.) and the Pidlite mine (Mora 

County, N. Mex.) and in lepidolite-rieh lenses at the Harding mine (Taos 

County, N. Mex.).

Uranium-bearing pegmatites in Africa, Mozambique, India, Brazil, 

Norway, Russia, and Canada are briefly described.

"In summary, the uranium minerals in foreign pegmatites, as well as in the 

United States, appear to be most common in those bodies that contain an 

abundance of potash feldspar. Uraninite shows a close association with 

muscovite and biotite; betafite and allanite with biotite; euxenite and 

monazite with beryl and in a few deposits with muscovite; and samarskite 

with columbite and fergusonite. Minor amounts of uranium minerals 

associated with lithium minerals have been noted. Nearly all the uranium
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 241

minerals are associated with some albite, but albite is rarely the dominant 

feldspar. [In part, the secondary uranium minerals are] apparently the 

result of alteration associated with the late stages of pegmatite formation 

rather than of weathering."

79 Patterson, C. C., Tilton, G. R., and Inghram, M. G. 1955, Age of the earth: 

Science, v. 121, P. 69-75.

This paper is mainly a discussion of a new method of age determination.

Evidence that there is a uniformity of elemental isotopic composition in 

both the earth and meteorites suggests that the concentrations of lead and 

uranium in chondrites may be a rough measure of the concentration of these 

elements in the earth as a whole. The uranium content of the following 

meteorites was determined:

Uranium

Canyon Diablo troilite.. ____ _ _____ ____ _ ___ 0. 009

Modoc total stone_____________________________________ . Oil

Norton County total stone ___ _________________________ . 010

Assuming that the earth is made of chondritic material, that it has a 

surface one-half covered by a 10-km-thick basaltic layer, one-half covered 

by a 10-km-thick granitic layer underlain by a 30-km-thiek basaltic layer, 

and using commonly accepted values for the concentration of uranium in 

granites and basalt, the authors present the following:

Earth's total 

Uranium uranium 

Material (ppm) (percent)

5 km of granite ___ __ _ _ _________________ 4 50

30 km of basalt- ___ _________________ _ .8 40

Interior_____________________________________ _ ___ 10

(Lead content and earth's total lead is also given but is not reported here.) 

The data suggest that nearly all the uranium in the earth is concentrated 

near the surface.

The mineral and chemical composition is given of a sample of Quaternary 

flood basalt from the Snake River Plains of Southern Idaho. The basalt 

contains 0.65 ppm uranium.

80 Phair, George, 1952, Radioactive Tertiary porphyries in the Central City 

district, Colorado, and their bearing upon pitchblende deposition: 

U. S. Geol. Survey TEI-247, 53 p., issued by U. S. Atomic Energy 

Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

Results of analyses [chemical and radiometric] of 117 samples indicated 

that the Tertiary porphyry sequence in the middle part of the Front 

Range ranks among the most radioactive igneous series in the world, according to the present literature. With the intrusion of nonporphyritic 

lime-poor quartz bostonite dikes in the western half of the Central City 

district, the magmatic enrichment in both uranium and thorium reached a 

peak of more than 20 fold over the best available averages for granitic 

rocks.

The sequence of events in the Central City district is thought to be as 

follows: (1) Intrusion of slightly to moderately radioactive monzonite 

throughout the eastern half of the district, (2) intrusion of excessively
242 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

radioactive, nonporphyritie varieties of quartz bostonite in the western 

half of the district north of what was to become the area of pitchblende 

deposition, (3) intrusion of the highly radioactive quartz bostonite porphyry dikes with which 15 of the 17 known occurrences of pitchblende 

are now associated (within 500 feet), (4) deposition of pitchblende as a local 

and unusual variant in the regional pyritic-gold ore deposition near, but 

not in, the quartz bostonite porphyry dikes. The implication of the field 

and chemical evidence is that uranium-rich solutions given off by a cooling 

quartz bostonite mass at depth became further enriched by leaching 

uranium from the quartz bostonite channelways while en route to higher 

levels. Zircon, the probable host for much of the uranium and part of the 

thorium in the rocks, separated in reduced amounts from the youngest 

quartz bostonite liquids a change which, in effect, tended to throw uranium into the residual liquid. Possible mechanisms by which uranium 

became concentrated with respect to thorium in the derived aqueous solutions are considered. In this connection the late magmatic introduction of 

fluorite and of ferric oxides may be of special significance. Author's abstract

81 Phair, George, 1955, Distribution of uranium in igneous complexes, in 

Geologic investigations of radioactive deposits Semiannual progress 

report, Dec. 1, 1954 to May 31, 1955: U. S. Geol. Survey TEI-540, 

p. 237-244, issued by U. S. Atomic Energy Comm. Tech. Inf. Service 

Ext., Oak Ridge, Tenn.

The results of heavy-mineral separations made on samples of Precambrian batholiths in the Colorado Front Range show the following: Monazite occurs only in the youngest batholiths; allanite is common in the Boulder 

Creek batholith (the oldest), occurs rarely in the "Silver Plume" correlatives, and is lacking in the Sherman and Pikes Peak batholithic rocks.

The average uranium content of samples of rocks of the White Mountain 

(N. H.) igneous series ranges from 4.7 ppm in the monzonites to 11.7 ppm 

in a biotite granite, the uranium content increasing from the oldest to 

youngest rocks. Zircon is the most uraniferous mineral in the Conway 

granite member of the White Mountain series.

The uranium content of allanites from acid and intermediate igneous 

rocks (exclusive of pegmatites) is variable.

"The main conclusions drawn from studies of the alkalic rocks in Sussex 

County, N. J., are (1) the relatively high-uranium contents (19-44 ppm) 

of these rocks show no relationship to the amounts of zircon or sphene, 

constituents in which the rocks appear to be abnormally enriched; and (2) 

in both the stock rocks and dike rocks uranium increases with SiO2."

82 Picciotto, E. E., 1950, Distribution de la radioactivity dans les roches 

eruptives: Soc. Beige geologic, paleontologie et hydrologie Bull., 

tome 59, p. 170-198.

This article presents the results of a study of thin sections of two granites 

an anorthosite, and a norite. Several generalizations are made about 

radioactivity in granitic rocks, based on previous work done by other 

authors. There seems to be no direct relation between radioactivity and 

concentration of major chemical constituents of the rocks; biotite is
UKANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 243

generally more radioactive than quartz, certain accessory minerals are the 

most radioactive, and part of the radioactivity is localized on the surface 

of the mineral grains of the rock.

The radioactivity data given in this article were obtained from stripping 

films and are expressed in units of alpha particles emitted per square 

centimeter per second.

Radioactivity in the Vosges granite is distributed in three ways: 54 

percent of the total radioactivity is concentrated in microscopic crystalline 

inclusions of accessory minerals (sphene, apatite, zircon), 28 percent of the 

radioactivity is dispersed among the essential minerals (quartz, biotite, 

feldspar), but much of it is probably caused by ultramicroscopic inclusions 

or atomic dispersion of the radioelements. It is possible that some of the 

radioactivity of quartz is due to liquid or gaseous inclusions. Eighteen 

percent of the radioactivity is concentrated in fractures cutting the minerals 

or in interstitial material.

The radioactivity in the accessory and essential minerals is of primary 

origin. Most of the radioelements separate out from the magma in the 

first stages of crystallization, zircon, apatite, and sphene being the first 

minerals formed in granite. A residual part of the radioelements is 

dispersed in the essential minerals, either in their crystal structure, by 

association with inclusions of zircon and apatite, or by association with 

the liquid or gaseous inclusions of residual magmatic fluids.

The radioactivity of the fracture fillings and interstitial material, which 

are composed of black opaque minerals and epidote, is of secondary origin.

A sample of granite from He d'Elbe contains quartz, orthoclase, plagioclase, and biotite as the essential minerals, and sphene, tourmaline, apatite, 

and opaque minerals as the accessory minerals, The quartz and feldspar 

have been crushed by tectonic action and exhibit the common effects of 

mechanical stress. Seventy-nine percent of the radioactivity is concentrated in the inclusions of accessory minerals; 18 percent is dispersed in 

the essential minerals; and 3 percent is confined to fracture fillings and 

interstitial material a low percentage considering the numerous cracks 

resulting from stress.

The radioactivity of a specimen of anorthosite from Egersund, Norway, 

is lower than that of the two granites studied, is much more homogeneously 

distributed, and is not due to inclusions. The ferromagnesian minerals 

are more radioactive than the feldspars.

A sample of norite from veins in the anorthosite massif has a slightly 

higher total radioactivity than the anorthosite.

83 Piggot, C. S., 1929, Radium in rocks I, The radium content of some 

representative granites of the eastern seaboard of the United States: 

Am. Jour. Sci., 5th ser., v. 17, p. 13-34.

This article presents the results of radium determination of seven 

igneous rocks from eastern United States. The apparatus, procedure, and 

calibration of the apparatus are described in detail. According to the 

author, "the radium determination is made by decomposing a weighed 

amount of pulverized rock by fusion in a flux of sodium and potassium 

carbonates, collecting the radium emanation thereby liberated, and determining it by means of an electroscope." The radium content is expressed
244 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

in terms of the unit, 10~12 grams of radium per gram of rock. The average 

radium contents of the rocks are given below.

84

LOCALITY

Stone Mountain, Ga__ 

Mount Airy, N. C____

Ilchester, Howard

County, Md. 

Woodstock, Baltimore

County, Md. 

Milford, Mass______

Roekport, Cape Ann,

Mass. 

Hurricane Island,

Maine.

BOCK TYPE

Fine-grained gray biotite-muscovite granite.

Coarse-grained light-gray biotite granite.

Gray biotite diorite with accessory epidote.

Gray biotite granite with 

much allanite and epidote.

Very light pink mottled biotite 

granite.

Hornblende-biotite granite_

Coarse even-grained pinkishbuff medium-gray biotite 

granite.

AVEEAGE

KADIUM

CONTENT io-» g/g

4.826

.655

1.935

1.448

.378

.955

NUMBER

OF

MEASUKEMENTS

16

4

5

5

5

5

3.740

The 48+100 mesh fraction of a sample of the Stone Mountain granite 

was separated into its constituent minerals according to density by suspension in Kline's solution, and a determination made of the radium content 

of each mineral. The results indicated that much of the radium is associated with the denser minerals, particularly with biotite and muscovite. 

The total radium content of all the minerals, however, is much less than 

the average radium content of the rock as a whole (4.826 X10~12 grams of 

radium per gram of rock). This indicates that much of the radioactivity 

is on the surface of the mineral grains and was leached during the separation 

process of the minerals. To test the theory, the author boiled a part of a 

powdered sample in distilled water and, after testing the radioactivity of 

the leached sample, found that a considerable portion of the radioactivity 

had been removed by the leaching. Further experiments by the author 

on the leaching of the radioactivity of granites are described in reference 86.

Piggot, C. S., 1931, Radium in rocks II, Granites of eastern North 

America from Georgia to Greenland: Am. Jour. Sci., 5th ser., v. 21, 

p. 28-36.

The radium content of granite samples discussed in reference 83 has 

been redetermined. The new values are as follows:

RADIUM 

LOCATION 10~12 K/K

Stone Mountain, Ga_____

Mount Airy, N. C_____-___-

Ilchester, Md_____________

Woodstock, Md__.._______

Milford, Mass___________

Rockport, Cape Ann, Mass__. 

Hurricane Island, Maine__ _

3.81

.49

.91

1.09

.26

.72

2.79
URANIUM GEOLOGY OF IGNEOUS AND METAMOEPHIC ROCKS 245

In addition, a sample of biotite-muscovite granite from North Jay, 

Maine, was examined. Five samples of this granite have an average 

radium content of 3.39X10"12 g per g. The author noted that the 

biotite in the granite contained many pleochroic halos, and he predicted 

correctly that because of this the granite might have a somewhat higher 

uranium content.

The radium content is given also for samples of igneous rocks from 

Labrador, Baffin-Land, and Greenland.

85 Piggot, C. S., 1931, Radium in rocks III, The radium content of Hawaiian 

lavas: Am. Jour. Sci., 5th ser., v. 22, p. 1-8.

The radium content of 13 samples of lavas from the Hawaiian Islands 

ranges from 0.75 to 1.47X 10~12 grams of radium per gram of sample, with 

an average of 0.96X10" 12 g per g. There was no correlation between 

radium content and age of flow all the samples representing a series of 

ancient to recent flows from Kilauea Crater had about the same radium 

content nor was there any correlation between radium content and the 

chemical composition of the lavas.

The basalts tested have as high an average radium content as that of 

any granites examined to date by the author.

86 Piggot, C. S., and Merwin, H. E., 1932, Radium in rocks IV, Location 

and association of radium in igneous rocks: Am. Jour. Sci., 5th ser., 

v. 23, p. 49-56.

Samples of granite from Stone Mountain, Ga., and North Jay, Maine, 

contain 3.8X10"12 and 3.39X10"12 grams of radium per gram of rock, 

respectively. The authors found no trace of radioactive minerals in the 

granite samples they examined, although both granites are known to have 

come from areas where such minerals have been identified.

Each sample was separated into a quartz and feldspar, a biotite, and a 

muscovite fraction. The radium content was determined for each fraction. 

The results of these analyses indicate that the radium content of the 

granites is associated more with the micas than with the other constituents.

Samples of the granites and of the various fractions were leached (boiled 

in distilled water, allowed to settle, and decanted). The residue was 

filtered and dried, and each sample divided into two parts. The radioactivity of one part was determined immediately, whereas the radioactivity 

of the other part was determined after 30 days. The results of these 

experiments showed that some of the radioactivity was leached from the 

samples, but that the loss was only temporary, as the radioactivity of the 

leached samples was completely restored after 30 days. Apparently, 

leaching removes only the radioactive material, which is weakly adsorbed 

on the sample or easily accessible in it, and has no effect on the original 

radium or parent uranium contained in the sample.

Preliminary experiments on the Stone Mountain granite are described 

in reference 83.

87 Poole, J. H. J., 1927, The radioactivity of the earth's basaltic magma: 

Philos. Mag., ser. 7, v. 3, p. 1246-1252.

This paper is for the most part a continuation of a study made by Poole 

and Joly in 1924 (reference 88). Poole makes a special study here of 

eclogites from Europe, the plateau basalts from Oregon, northwest Europe,
246 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

and India, and the island basalts from islands in the Atlantic and Pacific 

oceans. The electric method was used for the determination of the radium 

content and the solution method for the thorium content. Only the 

results of studies on the plateau basalts are included here.

The plateau basalts are divided into three groups: Oregonian from 

Oregon, Hebridean from northwest Europe, and Deccan from India. 

Poole's studies yielded the following results:

RADIUM THORIUM io-'2 g/g io-s g/g

Oregonian (mean for 12 samples)_________ 0. 70 0. 57

Deccan (mean for 6 samples)_____________ .77 .46

Hebridean (mean for 8 samples)------------ .77 .49

Mean for plateau basalts________________ .75 .51

88 Poole, J. H. J., and Joly, John, 1924, The radioactivity of basalts and 

other rocks: Philos. Mag., ser. 6, v. 48, p. 819-832.

The radium content (determined by the electric furnace-emanation 

method) and thorium contents are given for the following (only those 

rocks from the United States are listed here, although the report includes 

samples from other countries): Basalt from Colorado, Washington, and 

Montana; diabase from New Jersey, Massachusetts, and New York; 

hornblende gabbro from Virginia; peridotite from Rhode Island and New 

York; andesite from Colorado and Massachusetts; granodiorite from 

Minnesota; anorthosite from Oklahoma and New York; and dacite from 

Colorado.

Ultrabasic rocks are noted to have a lower radium content than mafic 

rocks. The paper is mostly concerned with the use of the radioactivity 

data as a means of arriving at an estimate of the radium content of the 

subcrustal magma of the earth.

89 Quirke, T. T., and Finkelstein, Leo, 1917, Measurements of the radioactivity of meteorites: Am. Jour. Sci., 4th ser., v. 44, p. 237-242.

Twenty-two meteorites were analyzed for radium using the emanation 

method. Among the samples tested were stone meteorites from Arizona 

and Kansas, an ironstone meteorite from Iowa, and iron meteorites from 

Kansas and Arizona. The other samples are from foreign sources. The 

authors found that all the siliceous meteorites were radioactive, in contrast 

to the iron meteorites which are almost free of radioactivity. From the 

data, it seems that the average stony meteorite is one-quarter or less as 

radioactive as the average granite.

90 Rankama, Kalervo, and Sahama, Th. G., 1950, Geochemistry: Chicago, 

111., Univ. Chicago Press, 912 p. See p. 178-180, 632-639.

The first part of this book is devoted to a general survey of the field 

of geochemistry and to the general laws and regularities that determine 

the abundance and mode of occurrence of each particular element. Part 

II is concerned with the geochemistry of the individual elements.

Heavy elements, such as uranium and thorium, are concentrated in 

the upper crust of the earth because of their property of becoming enriched 

in low-density rocks, such as granites and pegmatites.

Many complex pegmatites contain high concentrations of uranium 

because the ionic properties of uranium are not suitable for its incorporation into the structure of rock-forming minerals; and the uranium, 

therefore, becomes enriched in residual magmatic solutions. Uranium-
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 247

91

92

rich minerals are formed during the late stages of pegmatite deposition. 

Granite pegmatites have a higher concentration of uranium than 

nepheline syenite pegmatites.

Granitic rocks are richer in uranium than other igneous rocks. During 

crystallization the acidic rocks become enriched in uranium with respect 

to thorium.

Rodgers, John, 1952, Absolute ages of radioactive minerals from the 

Appalachian region: Am. Jour. Sci., v. 250, p. 411-427.

The author has assembled what he considers to be all the reliable analyses (for U, Pb, and Th) and determinations that have been made on 

minerals from the Appalachian region, in order to recalculate the age of 

the minerals "in the light of presently accepted formulae and constants."

Only those analyses not reported in any other annotation in this bibliography are listed below. All the uranium analyses except one were 

made using standard gravimetric chemical methods. The uranium content of uraninite from the Strickland quarry (item three) was determined 

by microanalytical methods. All the minerals are from pegmatites.

Uranium 

(percent)

6.91

Uraninite 71.32 Average of 5 

do_ ____ 78.78 Average of 3_

Location Mineral 

Spinelli quarry Samarskite. 

Glastonbury, 

Conn.

Hale quarry, Portland, Conn. 

Strickland quarry, 

Portland, Conn. 

Rock Quarry Land- ____do_____ 74. 39

ing, Haddam 

(Neck), Conn. 

Branchville, Conn. __do______ 74.67

(3 different anal- 66. 00 

ysts). 81. 50 

Deer Park mine, _.._do_____ 74.20 

Spruce Pine, 

N. C.

Flat Rock mine, __do_____ 67.00 1. 

Spruce Pine, 

N. C. 

Do-_______ Uraninite (be- 76.96

fore leaching . 

with HC1). 

Do _________ Uraninite (after 77. 77

leaching with 

HC1). 

Marietta, S. C_ __ Uraninite___ 71.19 1.

Number of samples 

Best mean of 2.

Average of 3. 

1_____________

Average of 2___ 

1_____________

Date of 

analysis

1937

1891

1933

1938

1891

1907

1880

1938

1907

1891

1891

1892

Senftle, F. E., and Keevil, N. B., 1947, Thorium-uranium ratios in the 

theory of genesis of lead ores: Am. Geophys. Union Trans., v. 28, 

p. 732-738.

(1) The analyses of group samples of over 1,500 igneous rocks indicate 

an average value for the thorium-uranium ratio of 3.4 for granitic rocks 

and 4.0 for intermediate rocks. Such values would give an atomic
248 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

weight of rock lead approximately that of ore lead and thus do not support Holmes' theory that lead ore deposits have a deep-seated source. 

(2) Experimental data indicate that the acidic magmas, while known to 

contain quantitatively more uranium and thorium than basic magmas, 

retain relatively more uranium than thorium than do intermediate magmas 

in the same region. (3) There is also some evidence that a regional 

distribution of thorium and uranium exists on the North American continent. The thorium-uranium ratios of the Canadian Shield are lower 

than in the United States. There is roughly a 20 percent higher uranium 

content in the intermediate rocks of the Canadian Shield, but this difference is not shown by the results in granitic composite samples. Authors' 

summary and conclusions

93 Shaub, B. M., 1938, The occurrence, crystal habit, and composition of the 

uraninite from the Ruggles Mine, near Grafton Center, New Hampshire: Am. Mineralogist, v. 23, p. 334-341.

Uraninite in pegmatite at the Ruggles mine occurs in all stages of alteration, from pitchy black crystals to an impalpable yellowish-white powder, 

together with an intermediate suite of uranium-bearing minerals which are 

distinct alteration products. The uraninite at this locality is unique in 

that it occurs chiefly as a three-dimensional dendritic intergrowth with 

perthitic feldspar, and also as skeleton crystals in the same material, but 

more commonly in albite intimately associated with perthite. Where the 

uraninite is intergrown with muscovite or occurs with smoky quartz, 

both the muscovite and the quartz are decidedly darker around the uraninite. This effect is probably a result of the radiation effects of uranium and 

its alteration products. A sample of fresh uraninite contains 76.38 percent 

uranium. A chemical analysis of the mineral is given.

94 Shaub, B. M., 1940, Age of the uraninite from the McLear pegmatite near 

Richville Station, St. Lawrence County, New York: Am. Mineralogist, 

v. 25, p. 480-487.

This article reports on a study of uraninite from a pegmatite in highly 

metamorphosed limestone of the Grenville series near Richville Station, 

N. Y. The uraninite is found as small cubes most commonly imbedded in 

white quartz. The author remarks that this is most unusual as the 

uraninite in quartz that he has observed at other localities has been associated with smoky rather than white quartz. No orange and yellow alteration products occur with the uraninite crystals which are generally fresh 

and unaltered. A microchemical analysis of one of the uraninite crystals is 

given, indicating a uranium content of 66.90 percent.

95 Sims, P. K., 1954, Radioactive Precambrian pegmatite, in Geologic 

investigations of radioactive deposits Semiannual progress report, 

June 1 to Nov. 30, 1954: U. S. Geol. Survey TEI-490, p. 137-139, 

issued by U. S. Atomic Energy Comm. Tech. Inf. Service Ext., Oak 

Ridge, Tenn.

A type of pegmatite, abnormally radioactive over a wide area in Clear 

Creek and Gilpin Counties [Colo.], appears promising locally as a substantial source of low-grade uranium ore. The uranium mineral is 

uraninite.

A radioactive pegmatite on the Highlander claim in Virginia Canyon, 

about a mile north of Idaho Springs, is being mined from the Hudson tunnel
URANIUM GEOLOGY OF IGNEOUS AND METAMOEPHIC BOCKS 249

and is one of several radioactive pegmatites in this part of Virginia Canyon. 

The pegmatites individually are lenticular bodies from a foot or less to about 

30 feet thick and a few tens to perhaps & hundred feet long. They crosscut the metasedimentary rocks they intrude. They consist predominantly 

of perthite, quartz, plagioclase, and biotite. The uraninite largely isassociated with the biotite. At and near the surface uranophane and 

autunite are present. Other minerals include pyrite and molybdenite.

Geiger-counter radioactivity measurements on the pegmatite gave ao 

average of 0.2 mr per hr and a maximum of 0.5 mr per hr. Another pegmatite, 25 feet thick, gave similar readings. Preliminary data suggest that 

the pegmatites in the tunnel contain on the average slightly more than 

0.1 percent uranium. A higher grade product can be obtained by hand 

sorting; some pegmatite containing 1 percent or more uranium is present.

Other bodies of the same type of pegmatite, equally as radioactive, are 

known. They include the pegmatite on the Waterloo dump in Russell 

Gulch.

The radioactive pegmatite is thought to be related to the biotite-museovite granite of the area, which is also more radioactive than the other 

granitic rocks and metasediments. Extracts from author's report

96 Smith, W. L., and Flanagan, F. J., 1956, Use of statistical methods to 

detect radioactivity change due to weathering of a granite: Am. Jour. 

Sci., v. 254, p. 316-324.

Forty-four samples of the Conway granite were collected from the red 

and green phases of the rock at the Redstone, New Hampshire, quarries. 

A large variation in radioactivity as measured by ^-counting is shown between individual samples.

Inspection of the data shows that the red phase is higher in radioactivity 

than the green. An analysis of variance with a single variable of classification shows that the means of the fresh and weathered red phases are not 

significantly different, whereas a "t" test using differences between pairs 

of the fresh and weathered green samples shows that the means of these 

two sets differ significantly. From these tests and a comparison of the 

variances of the respective sets, it is inferred that weathering has had a 

significant effect on the green phase only.

It has been shown, by comparing the variance of the subsets of data 

with the known variance of the method of measurement, that some external factor such as variations in mineralogic composition or differential 

leaching or adsorption may be responsible for the variations in radioactivity. Authors' abstract

97 Stewart, R. H., 1951, Radiometric reconnaissance examination in southeastern Pennsylvania and western New Jersey: U. S. Geol. Survey 

TEM-255, 13 p., issued by U. S. Atomic Energy Comm. Tech. Inf. 

Service Ext., Oak Ridge, Tenn.

A radiometric reconnaissance with a car-mounted Geiger counter was 

made of 350 miles of road in southeastern Pennsylvania and western New 

Jersey.

A mineralized diabase dike in Flemington, N. J., had the lowest uranium 

content (0.00 percent) of any of the igneous or metamorphic rocks examined. A chip sample of a Preeambrian granite dike at Glen Gardner, 

Hunterdon County, N. J., contains 0.002 percent uranium. Granite 

gneiss, the host rock of the dike, contains 0.001 percent uranium. The
250 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

uranium content of samples of the Picketing gneiss in the Chestnut HillMarble Mountain area near Easton, Northhampton County, Pa., ranged 

from 0.004 to 0.008 percent.

"98 Stow, M. H., 1955, Report of radiometric reconnaissance in Virginia, 

North Carolina, eastern Tennessee, and parts of South Carolina, 

Georgia, and Alabama: U. S. Atomic Energy Comm. RME-3107, 

33 p., issued by U. S. Atomic Energy Comm. Tech. Inf. Service Ext., 

Oak Ridge, Tenn.

The author conducted a radiometric reconnaissance of 10,000 miles of 

road in Virginia, North Carolina, South Carolina, Tennessee, Georgia, 

and Alabama. Igneous, sedimentary, and metamorphic rocks are represented in the area examined. Localities with an abnormal radioactivity 

of more than twice background (both a Geiger and a scintillation counter 

were used) are described briefly and are shown on the index and generalized 

geologic maps that accompany the report. Background was 0.025 mr per 

hr.

The Lovingston granite gneiss is abnormally radioactive at two places 

in Virginia; north of Culpeper, Culpeper County, and northeast of Charlottesville, Albemarle County. The rock at both localities is biotite-quartz 

monzonite and augen gneiss. Analyses of two samples from the Culpeper 

area gave 0.068 and 1.2 percent equivalent uranium and 0.009 and 0.083 

percent uranium, respectively. Monazite was determined to be the source 

of the radioactivity. At the Charlottesville locality, the radioactivity is 

concentrated in a zone of weathered schist and gneiss. One sample contains 0.40 percent equivalent uranium and 0.006 percent uranium. The 

radioactivity is probably due mainly to thorium.

Analyses of two samples of magnetite-bearing schist near Chestnut Knob, 

Henry County, Va., gave the following results: 0.054 and 0.065 percent 

equivalent uranium and 0.003 and 0.004 percent uranium.

Anomalous radioactivity as high as 0.40 mr per hr was detected in the 

Grayson granite gneiss at several localities in Grayson County, Va.

The Cranberry granite was abnormally radioactive wherever it was 

tested. All the radioactive areas are in proximity to prominent fault 

zones. In the vicinity of Hampton, Carter County, Tenn., analyses of 

several samples of the granite ranged from 0.043 to 0.15 percent equivalent 

uranium and from 0.018 to 0.11 percent uranium. In Burke County, 

N. C., the radioactive minerals are localized in schistose zones and shear 

zones. Uraninite has been identified in veins and schistose zones in 

the Cranberry granite in Avery County, N. C. The author concludes 

that favorable conditions for concentration of uranium minerals exist 

in the Cranberry granite where it has been faulted and sheared.

Samples of Precambrian hornblende schist and gneiss in the vicinity of 

Jefferson, Ashe County, N. C., contain 0.068 to 0.33 percent equivalent 

uranium and 0.57 to 0.22 percent uranium.

99 Taylor, A. O., and Powers, J. F., 1955, Uranium occurrences at the Moonlight mine and Granite Point claims, Humboldt County, Nevada: 

U. S. Geol. Survey TEM-874A, 16 p., issued by U. S. Atomic Energy 

Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn. See p. 4-7, 

14-16.

The Granite Point claims are at the base of a rhyolite cliff in sees. 4 and 

5, T. 45 N., R. 34 E., Humboldt County, Nev. A soft green intensely
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 251

altered diabase intrusive rock is exposed in three places under the rhyolite 

cliff and is believed to be one of a group of small discontinuous dikes. 

The highest radioactivity at the property was noted in the rhyolite at the 

base of the cliff and ranges from 0.013 mr per hr to 0.30 mr per hr with an 

. average of 0.10 mr per hr. A sample from the most radioactive part of 

the rhyolite contained 0.02 percent uranium. The radioactivity of the 

diabase ranges from 0.013 mr per hr to 0.03 mr per hr.

100 Tomkeieff, S. I., 1946, The geochemistry of uranium: Sci. Prog., v. 34, 

p. 696-712.

Available evidence indicates that the radioactive elements are concentrated in the outer shell of the earth's crust, and that granitic rocks and 

rare-earth pegmatites contain more uranium than other types of igneous 

rocks. Uranium is concentrated in the accessory minerals of granitic 

rocks rather than in the common rock-forming minerals.

Uranium-bearing minerals may be classified genetically as orthomagmatic 

and pegmatitic, hydrothermal and supergenic, and biogenic. Uraniumbearing minerals also can be grouped into high- and low-temperature 

assemblages. The high-temperature minerals are characterized by thorium, lead, rare earths, tantalum, niobium, and titanium and are found 

in pegmatites and as accessory minerals in granite. The low-temperature 

minerals are not commonly found in igneous rocks.

"The concentration of uranium in pegmatites and hydrothermal veins 

is probably determined by the nature of the elements likely to form stable 

compounds with uranium, the relative abundance of these elements, and 

temperature-pressure factors."

101 Tourtelot, H. A., 1952, Reconnaissance for uraniferous rocks in northeastern Wind River Basin, Wyoming: U. S. Geol. Survey TEM-445, 

14 p., issued by U. S. Atomic Energy Comm. Tech. Inf. Service 

Ext., Oak Ridge, Tenn.

A reconnaissance search for uraniferous rocks in the northeastern part 

of the Wind River Basin was made in July and August 1951 in the course 

of other work. In addition to Tertiary tuffs and associated lignite, coal, 

and carbonaceous rocks, some radioactivity anomalies, chiefly in granite, 

which had been detected by airborne equipment in November 1950, were 

checked on the ground. A tuff of middle or late Eocene age containing 

0.003 percent uranium was as high in uranium as any rock found. One 

sample of [Precambrian] granite [Fremont County] also contained 0.003 

percent uranium. The equivalent uranium content of the granite was two 

to five times as large as the uranium content, presumably due to the 

presence of thorium. Author's abstract, in part

102 Urry, W. D., 1933, Radioactivity measurements I, The radium content of 

the Keweenawan basalts and some accessory minerals: Am. Acad. 

Arts and Sci. Proc., v. 68, p. 125-136.

The radium content of 23 samples of basaltic and felsitic flows, and accessory minerals from the copper mines of Keweenaw Point, Mich., was 

determined by the emanation method. An increase of radioactivity with 

depth was noted at the Champion, and Calumet and Hecla mines. Samples of felsitic flows contain more radium than the basaltic flows. The 

radium content is higher in the younger flows than in the older flows, 

indicating that there is a definite correlation between radium content and
252 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

the age of the flow. The plateau basalts of the Keweenaw district have an 

average radium content (mean value) of 1.29X10"13 grams of radium per 

gram of rock.

The radium content of samples of the copper arsenides algodonite and 

domeykite is almost directly proportional to the amount of arsenic in the 

mineral. The author suggests that this is evidence of "a regular order in 

the radium content of the accessory minerals in the copper lodes according 

to the method of precipitation from the mineralizing solutions."

103 Urry, W. D., 1933, Radioactivity measurements II, The occurrence of 

radium, uranium, and potassium in the earth: Am. Acad. Arts and 

Sci. Proc., v. 68, p. 137-144.

The author presents the following pattern of the distribution of uranium 

and radium throughout the earth, basing his calculations on Washington's 

proposed mineralogical and chemical structure, 1 and using published analyses of various rock types.

RADIAL RADIUM URANIUM 

THICKNESS 10~14 10~7

(Km) g/g g/g

Central core_____________________ 3400 2.5 0.74

Lithosporic shell________________ 700 7.0 2.06

Ferrosporic shell..______________ 700 12.0 3.53

Peridotitic shell....________________ 1540 20.0 5.88

Basaltic shell____ ___ ____________ 40 28.0 8.24

Granitic shell..__________________ 20 140.0 41.18

The analyses indicate that radioactivity decreases with depth.

104 Urry, W. D., 1936, Ages by the helium method II, Post-Keweenawan: 

Geol. Soc. America Bull., v. 47, p. 1217-1233.

This article is primarily a discussion of age determinations by the helium 

method.

The radium content (X 10~ 13 g per g), thorium content (X 10~6 g per g), 

and the helium content (X10~6 cc per g) is given for samples of basic 

igneous rocks representative of most of the geologic horizons from Cambrian through Pliocene. The specimens include basalts from Washington, Oregon, Tennessee, Pennsylvania, and Massachusetts; trap rock from 

New Jersey, Connecticut, and New York; and diabase from Pennsylvania. 

Brief geologic and mineralogic notes are given for most of the specimens.

105 Watson, T. L., 1902, On the occurrence of uranophane in Georgia: Am. 

Jour. Sci., 4th ser., v. 13, p. 464-466.

At Stone Mountain, Ga., uranophane is an incrustation on joint planes 

of the Stone Mountain granite. The uranophane is "tipped" or coated 

with hyalite and contains 52.08 percent uranium.

106 Wedow, Helmuth, Jr., 1954, Reconnaissance for radioactive deposits in 

the Eagle-Nation area, east-central Alaska, 1948: U. S. Geol. Survey 

Circ. 316, 9 p.

Reconnaissance of radioactive deposits in sedimentary rocks of Proterozoic and Paleozoic age, and granite of Mesozoic(?) age together with 

its Tertiary sedimentary derivatives, was conducted in the Eagle-Nation

Washington, H. S., 1925, The chemical composition of the earth: Am. Jour. Sci., 5th ser., v. 9, p. 351-378.
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 253

area, east-central Alaska, in 1948 * * *. Samples of the granite of 

Mesozoic(?) age and its Tertiary sedimentary derivatives average 0.005 

and 0.004 percent equivalent uranium, respectively. Biotite is the chief 

radioactive mineral in the granite, and its radioactivity is ascribed to the 

presence of uranium and thorium, which occur either as impurities or in 

minute inclusions of other, as yet unidentified, minerals. Traces of uranium and thorium in zircon, sphene, and monazite also contribute to the 

total radioactivity of the granite. Zircon and monazite are the major 

uranium- and thorium-bearing minerals of the Tertiary sedimentary rocks 

derived from the granite. Author's abstract, in part

107 Wedow, Helmuth, Jr., and Matzko, J. J., 1954, Areas adjacent to highways 

in the Tanana and Upper Copper River valleys, Chap. A of Reconnaissance for radioactive deposits in eastern interior Alaska, 1946: 

U. S. Geol. Survey Circ. 331, p. 1-32.

Graphitic schists in the Tanana and Upper Copper River valleys in 

eastern interior Alaska contain a maximum of 0.004 percent equivalent 

uranium. Other types of schist have a lower radioactivity as much as 

0.003 percent equivalent uranium. Granite and mafic rocks tested have 

maximums of 0.006 and 0.005 percent equivalent uranium, respectively. 

The radioactivity of the igneous rocks is probably due to traces of uranium 

and thorium in accessory minerals, such as zircon and allanite.

108 Wedow, Helmuth, Jr., and Tolbert, G. E., 1954, Wilson Creek, My Creek, 

Ben Creek, and Chicken areas, Fortymile district, Chap. E of Reconnaissance for radioactive deposits in east-central Alaska, 1949: 

U. S. Geol. Survey Cire. 335, p. 13-22.

A maximum of 0.005 percent equivalent uranium was found in felsic 

igneous rocks of the Wilson Creek and Ben Creek areas. The radioactivity 

of these rocks in the Wilson Creek area is probably due to traces of radioactive elements in the common accessory minerals of the igneous rocks; 

in the Ben Creek area it is probably due chiefly to thorium in monazite 

and allanite, which were identified in concentrates from gravels of streams 

draining areas underlain by the igneous rocks. Authors' abstract, in part

109 Wells, R. C., 1934, Allanite from Wyoming: Am. Mineralogist, v. 19, p, 

81-82.

A chemical analysis was made of a sample of allanite from a pegmatite 

northwest of Wheatland, Wyo. The mineral contains 0.017 percent 

uranium.

110 West, W. S., and Matzko, J. J., 1954, Hope Creek and Miller HouseCircle Hot Springs areas, in Nelson, A. E., West, W. S., and Matzko, 

J. J., Reconnaissance for radioactive deposits in eastern Alaska, 1952: 

U. S. Geol. Survey Cire. 348, p. 7-15.

The equivalent uranium content ranges from 0.001 to 0.005 percent for 

granite samples and from 0.002 to 0.004 percent for aplitic dike samples 

in the Miller House-Circle Hot Springs area, Alaska. The author's summary, in part, is as follows:

A wide variety of radioactive minerals were found to occur in granite. 

Certain uranium-bearing minerals in the Miller House-Circle Hot Springs 

area, which are also belived to contain uranium in the Hope Creek area, 

appear to be primary accessory minerals in the granite. Other minerals,
254 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

such as fluorite, topaz, and several metallic sulfides in both areas, and 

cassiterite and wolframite in the Miller House-Circle Hot Springs area, 

were probably formed as a result of pneumatolytic action after the crystallization of the magma or during the late stages of crystallization. Some 

of the minerals in the latter group are known to be uranium bearing; 

therefore, it seems likely that hydrothermal solutions were partly responsible for the introduction of uranium during the process of pneumatolysis.

111. West, W. S., and White, M. G., 1952, The occurrence of zeunerite at 

Brooks Mountain, Seward Peninsula, Alaska: U. S. Geol. Survey Circ. 

214, 7 p.

Zeunerite occurs near the surface of a granite stock on the southwest 

flank of Brooks Mountain, Alaska. The largest deposit is at the Foggy 

Day prospect. Zeunerite is disseminated in hematite which partially or 

totally fills openings and vugs in a highly oxidized lens-shaped body of 

pegmatitic granite and, to a minor extent, in openings and cracks in the 

weathered granite enclosing the lens. Although a few specimens from the 

pegmatitic lens contain as high as 2.1 percent equivalent uranium, the 

average content of the lens rocks is between 0.1 and 0.2 percent equivalent 

uranium and that of both the lens material and the surrounding zeuneritebearing granite is about 0.07 percent equivalent uranium. Authors' 

abstract, in part

The granite of Brooks Mountain has an average equivalent uranium 

content of about 0.005 percent. The amount of radioactivity is directly 

proportional to the quantity of zircon, monazite, and xenotime in the 

granite.

Analytical data are given for selected samples.

112 White, M. G., 1952, Reconnaissance for radioactive deposits along the 

upper Porcupine and lower Coleen Rivers, northeastern Alaska: 

U. S. Geol. Survey Circ. 185, p. 6-9.

A radiometric reconnaissance was made of a granitic intrusive and of 

lava flows in the Porcupine River area, Alaska. The rhyolitic rocks are 

slightly more radioactive than the granite. The radioactivity of the 

samples collected was due to one or more of the following: Biotite, elarkeite, 

hematite with uranium as an impurity, surficial weathered parts of pyrite,. 

rutile, and three unknown minerals.

The Tertiary lava flows are not radioactive.

113. White, M. G., 1952, Radioactivity of selected rocks and placer concentrates from northeastern Alaska: U. S. Geol. Survey Circ. 195, p. 1-7.

Radiometric examination of 13 samples collected in the Mount Michelson 

area, northeastern Alaska, in 1948, shows that four samples of gneissic 

granite contain an average of 0.007 percent equivalent uranium. The 

heavy-mineral fractions from 3 of these 4 samples contain an average 0.052 

percent equivalent uranium and 0.03 percent uranium. The heavy-mineral 

fractions of panned concentrates from gravels of streams draining relatively 

large areas of granitic rock, contain an average of 0.028 percent equivalent 

uranium, whereas similar heavy fractions of panned concentrates from
URANIUM GEOLOGY OP IGNEOUS AND METAMORKEHC ROCKS 255>

streams that drain areas other than those largely underlain by graniticrock contain an average of only 0.005 percent equivalent unranium.

Mineralogic study of all heavy-mineral fractions having more than 0.01 

percent equivalent uranium indicates that the radioactive material apparently is confined to biotite, which in one sample contains 1.19 percent, 

uranium. Fluorite, hematite, zircon, sphene, galena, and molybdenite, 

commonly associated elsewhere with uranium, apparently are disseminated 

in the granite with the biotite.

The presence of uranium in the biotite of the granite and of other minerals, associated with uranium elsewhere, suggests that this area should beconsidered in relation to others in Alaska as a possible locality to search for 

high-grade uranium deposits. Author's abstract

114 White, M. G., and Killeen, P. L., 1953, Reconnaissance for radioactivedeposits in the lower Yukon-Kuskokwim highlands region, Alaska: 

U. S. Geol. Survey Ore. 255, p. 1-10.

Radioactivity in the vicinity of Flat, Alaska, was found to be concentrated in zircons disseminated in a coarse-grained light-colored facies of 

monzonite. The zircons contain as much as 0.14 percent equivalent uranium and 0.12 percent uranium. The radioactive elements seem to be concentrated in reddish-brown inclusions in the zircon crystals.

Apatite is also radioactive the equivalent uranium content ranges fromi 

0.008 to 0.01 percent. The biotite fraction of the monzonite is slightly 

radioactive (0.004 percent equivalent uranium), but the radioactivity isprobably due to minute inclusions of zircon and allanite (?).

115 White, M. G., and Stevens, J. M., 1953, Reconnaissance for radioactive 

deposits in the Ruby-Poorman and Nixon Fork districts, west-central 

Alaska: U. S. Geol. Survey Circ. 279, p. 1-9.

Reconnaissance for radioactive deposits in the Ruby-Poorman district, 

Ruby quadrangle, central Alaska, during July 1949, showed that two small! 

bodies of granite in the Long area, about 30 miles south of Ruby, contain 

an average of 0.005 percent equivalent uranium. This radioactivity isdue chiefly to a uraniferous thorium silicate, tentatively identified asuranothorite, which is disseminated in the granite. Other minerals, such assphene, allanite, and zircon, that contain radioactive elements as impuritiesalso contribute to the total radioactivity of the granite. The uranothorite(?) contains about 57 percent thorium and 8 percent uranium. 

Authors' abstract, in part

116 White, M. G., and Tolbert, G. E., 1954, Miller House-Circle Hot Springsarea, Chap. B of Reconnaissance for radioactive deposits in eastcentral Alaska, 1949: U. S. Geol. Survey Circ. 335, p. 4-6.

Granite of Mesozoic(?) age in the Miller House-Circle Hot Springs area,, 

east-central Alaska, contains 0.005 to 0.007 percent equivalent uranium.. 

The radioactivity is mostly caused by uranium in such primary accessory 

minerals of the granite as allanite, garnet, scheelite, sphene, and zircon*. 

However, the presence of metallic sulfides, cassiterite, and uraniferousfluorite, malachite, and topaz in the granite or associated placers suggests^ 

the possibility of a post-emplacement or late-stage mineralization of the-
256 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

granite, presumably of hydrothermal origin, as a source for at least part of 

the uranium. Additional reconnaissance in the area to determine the 

presence or absence of hydrothermal uraniferous deposits of commercial 

grade appears warranted. Authors' abstract

117 Young, R. W., and Muench, 0. B., 1953, The Chemical analysis of an 

euxenite for age determination: Am. Jour. Sci., v. 251, p. 784-788.

The average uranium content of two samples of euxenite from a pegmatite 

at Bull Creek, near Pecos, N. Mex., was 4.010 ±0.050 percent. Other 

constituents of the mineral also were determined. An autoradiograph 

showed the mineral to be very uniform in radioactivity.
INDEXES

AUTHORS

Reference 

No.

Adams, J. A. S_.__.....___.____ 1,2,3,4 

Altschuler, Z. S_______..__._.__ 5 

Amstutz, Q. O__________________ 6 

Auer, M. L__________________ 64

Barth, Tom. F. W_........................ 7

Becraft, O. E___._______........__ 8

Berman, Joseph________________ 56 

Billings, M. P.____.....__............... 9

Blake, W. J.................................. 10

Brown, Harrison_________________ 10,11

Chodos, A. A_____.______.___._ 10

Clarke, R. S., Jr.. ........................ 5

Coats, R. R__. __. ___. ___.. ____ 12

Crombie, O. P_________.___.__ 46

Dalton, J. O.._________._______ 13 

Daniels, Farrington_______________ 76 

Davidson, O. F__....______.____ 14 

Davis, O. L............................... 15,16,17

Derville, R. P____.___..___.___._ 29 

DeVore, Q. W_...__...._._.___.. 18

Eckel, E. B___...______._.____ 19 

Emmons, R. C__________________ 20 

Evans, R. D......_............_......... 21,22

Fairbairn, H. W. 

Finkelstein, Leo., 

Flanagan, F. J... 

Foye, W. Q__.. 

Furcron, A. S_.

Gabriel, V. O________________... 25

Glass, J. J___.._______________ 30

Golden, J._. _____________. __ 13

Goldschmidt, V. M___________.__ 26

Goodman, Clark________________ 21 

Gottfried, David,...______......_ 27,34,56,74

Gross, W. H.................................. 28

Harrison, H. C__________________ 53

Hee, Arlette.................................. 29

Hess, H. H___________________ 17

Hewett, D. F___.______________ 30

Holmes, Arthur________________ 31

Hurley, P. M._...........__._.____ 32,33

Hutchinson, R. M__.____________ 34

Hutton, C. O___....___________ 35

Ingham, W. N..............__..__.__ 46

Inghram, M. G___________.____ 79

Reference 

No.

Jafle, H. W.. . _ ......... . _ ....... 34

Jahns, R. H_. _______ .... ___ . _ ... 36

Jarovoy, Michel _______________ ...- 29 

Jeffreys, Harold.............. ___ . __ .... 37

Johnson, D. H... ......... _ .... _ . _ ..... 38

Joly, John...-..............-......... . 39,40,88

KeevD, A. R. _________________ .. 46 

Keevil, N. B .... 9, 41, 42, 43, 44, 45, 46, 47, 51, 52, 53, 92

Killeen, P. L ... _ ... .. _ ................ 114

Klemic, Harry __________________ 59' 

Kowalkowski, Richard __________ 10-

Lane, A. C. ...... .................. 23.48,49

Larsen, E. S., Jr. . 47, 50, 51, 52, 53, 54, 55, 56 

Love, J. D.-_- ____ . ___ .. _____ . 57 

Lovering, T. S ____ . ___ . ________ 19

McKeown, F. A _______________ 68,59,70 

McKinney, C. R ________ . ________ 10' 

Marble, J. P..... . 60,61,62,63

Martin, G. R___ . .. .. . . 13 

Matzko, J. J............ ........ __ ....... 107, 110-

Mead, Judson ________ . _______ 76 

Mercer, E. R _________________ 13 

Merwin, H. E........ _ .... _ .._. 86

Morgan, J. H ________________ 64 

Moxham, R. M __ . ________ .... ___ 65,6fr

Muench, 0. B......................... 67,68,69,117

Narten, P. F. .......... __ . ________ .. 70,71

Nelson, A. E................................. 65-

Nelson, J. M ............................. 71

Neuerburg, G. J.... _ .. __ . _ ...... 10,72,73,74

Neumann, Henrich ____________ 75-

Ockerman, J. B ______________ ... 76 

Ordway, R. J _____ . _ 7T

Page, L. R. . 78 

Patterson, C. C ... .. . 79 

Phair, George _ . ___________ 64,55,80,81 

Picciotto, E. E ________________ ... 82- 

Piggot, O. S _ . . ..- 83,84,85,86 

Poole, J. H. J-... ... ....... ..... .. 87,88

Powers, J. F _________________ 99-

Quirke, T. T

Rankama, Kalervo. 

Reynolds, C. D.... 

Rodgers, John......

90- 

20> 

91

257
258 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Reference 

No.

Bahama, Th. O________________ 90 

Saunders, D. P.._______.... ...-....- 3,4,20

Senftle, F. E_............................. 92

 Shaub, B. M................................. 93,94

Silver, L. T...__......__..___................ 10,11

Sims, P. K._______._._._.__... 95 

Smith, W. L__............................. 55,96

Stevens, J. M_________________ 115 

Stewart, B.H.______.________________________ 97

Stow, M. H__.............................. 98

Taylor, A. O _______....._._. _ 99

Thompson, 8.J.............................. 13

Tilton, O. B.___......................... 79

Tolbert, Q. E__........ ..___._._._..__ 108,116

TTomkeieff, S.I............................... 100

Tourtelot, H. A.............................. 101

Reference 

No.

Uchiyama, Aijl__......____ . 10

tlrry, W. D......................... 49,102,103,104

Vitaliano, O. J............................... 7fi

Wank, F. J......................__.__ 47

Waring, C. L.__....... . ... 56

Watson, T. L ___.. .. . 105 

Wedow, Helmuth, Jr........... ..... 106,107,108

Wells, B. C..........._.... ............ 109

West, W. 8... . . . 66,110,111 

White, M. O...-..... ... 111,112,113,114,115,116

Williams, Howel - . 22

Young, E. J_____.._.- . . 5 

Young, B. W_... ..- . 117

Zeller, E. J.
URANIUM GEOLOGY OF IGNEOUS AND METAMORPHIC ROCKS 259

GEOGRAPHIC AREAS

Reference 

No.

Alabama___________________ 98

Alaska.

Ben Creek area.._____________ 108 

Eagle-Nation area_____________ 106 

Flat area__________________ 114 

Hope Creek area..____________ 110 

Miller House-Circle Hot Springs area.. 110,116 

Mount Michelson area__________ 113 

Ruby-Poorman district__________ 115 

Seward Peninsula:

Brooks Mountain___________ 111 

Serpentine-Kougarok area______ 66 

Tanana and Upper Copper River valleys. 107 

Upper Porcupine River area_______ 112 

Willow Creek mining district_______ 65 

Wilson Creek area.____________ 108 

WrangeL.___.___._________ 43

Argentina.

Salta meteorite______________ 16

Arizona.

General..__.__ ________ 12 

Canyon Diablo meteorite_________ 79 

Superior district________._____. 45

Arkansas.

Hot Springs.__..._____.__._ 43 

Magnet Cove_______________ 43

Ascension Island_______________ 4

Australia.

Queensland, Thunda meteorite 16

California.

General___-_._.____..____ 12, 46 

Los Angeles County, San Gabriel Mountains _______.__ ... 74 

Modoc County, Modoc lavas______ 50, 55 

San Bernardino County:

Cady Mountains___________ 30 

Pomona Tile quarry.. _____ 30 

Shasta County, Lassen Volcanic National

Park_..__________ 1, 2, 3, 21 

Sierra Nevada.____________ 27, 50, 55 

Southern California batholith. 27, 51-55 

Tuolumne County, Yosemite National

Park............................. 35

Canada.

General..... . __...... 28, 44, 92

Bourlamaque batholith .... . . 46

Nova Scotia._-_-_-_.. . 33

Ontario.-... ._._.___.____ 33

Sudbury________________ 33

Ceylon_____.___.._ . 33

Chile.

Antofagasta meteorite.._______ . 16 

Sierra Gorda meteorite. 16 

Colorado.

General-. .._......_.___.... 12, 40

Chaffee County, Trout Creek Pass. 69 

Douglas County, Devil's Head Mountain._____ 31 

Eagle County, Oilman.....__.... 45

Reference 

No.

Colorado Continued

Front Range...__.__....____ 27, 81,95

Boulder Creek batholith.. _ 50, 55, 81 

Central City district_________ 80 

Gunnison County:

Brown Derby pegmatite. _____ 78

Ohio City . . . 19

Montezuma County, Mesa Verde____ 16

Park County, Trout Creek Pass..._._ 69

San Juan Mountans._ ...-_.- ... 27, 55

Shaw meteorite______________ 16

Connecticut.

General 58,104

Branchville____-________ 31,91 

Glastonbury__-_-__________ 31, 91 

Haddam Neck...._.. 91

Portland __ 23,91

Europe-___ 87

Finland______________________ 7 

France.

Vosges Mountains 82

Georgia.

General..___ 98

Cedartown meteorite__ 16

DeKalb County, Stone Mountain. 24,

83, 84, 86,105

Greene County...- 24 

Jasper County 24 

Lamar County.____-. 24

Hawaiian Islands. 85

Idaho.

General.__.___ . 12 

Coeur d'Alene district._________. 45 

Idaho batholith.. .- 27,50,55 

Snake River Plains...- 79

India 87

Iowa.

Meteorite...-_- 89

Italy.

De d'Elbe (Elba Island)..-.. 82 

Liparii. 4

Japan.

Shizuoka Prefecture__ 4

Kansas.

Brenham meteorite 13,16 

Meteorites_... 89 

Modoc meteorite 79 

Norton County meteorite 79

Kentucky.

Cumberland Falls meteorite 16 

Edmonton meteorite 16

Maine.

General- - 33,46,71,77

Franklin__________________ 42 

Hurricane Island 83,84 

North Jay 84,8

Rumford, Red Hill pegmatites 77
260 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Reference

Maryland. No. 

Baltimore County, Woodstock._____ 83,84 

Howard County, Ilchester________ 83,84

Massachusetts.

General-- ______ 33,38,40,58,104 

Blueberry Mountain__.________ 31 

Cape Ann granite_________ 41,42,83,84 

Chelmsford granite________.-__ 42,47 

Fitchburg granite _ ___ _ 42,48 

Greenwich._______..._______ 63 

Milford _..._. __ 83,84

North Attleboro..__....._....._.... 43

Quincy granite..____________ 29,42,46 

Southbridge .-_.... . ... .._ 38

Worcester__ __ ___ ._ 38

Michigan.

General_ ________________ 43,46 

Keweenawan basalts.__________ 49,100 

Lake Superior region... ____ _ 64 

Minnesota.__._____._______ 88

Montana.

General__...._____________ 12,88 

Boulder batholith_.__.____.__ 8, 50 

Highwood and Bearpaw Mountains -.. SO, 55

Nevada.

General_________.....__ __ 12,46

Humboldt County____.______._ 99

New Hampshire.

General._________________ 9,53,58 

Grafton area, Ruggles mine .... . 78,93 

Groton area, Palermo pegmatite__.__ 78 

White Mountain magma series__ 9,27,81 

Conway granite _._._.... 50,54,55,81,96

New Jersey.

General 43,46,88,97,104

Highlands.. ______...__...__ 59 

Hunterdon County_... . 97 

Morris County, Canfield phosphate mine. 59 

Palisades. . __..___....... 46

Sussex County .._ 42,43,45,50,81 

Warren County____ ___..__ 59

New Mexico.

Glorieta meteorite___....___..__ 16 

Mora County, Pidlite mine ______ 78 

Rio Arriba County, Petaca 31 

San Miguel County:

Pecos_________________ 117 

Taos County, Harding mine _ 78 

New York.

General.__.......________ 46,58,88,104

Adirondack Mountains..._________ 59,70 

Clinton County, Rutgers mine_____ 59 

Essex County:

Mineville district___________ 59,62

Port Henry. _.. 43

Whiteface Mountain-..__... ... 62

Hudson Highlands____________ 58

Hudson Valley ______________ 70

Palisades_________________ 46

St. Lawrence County:

Benson mines...___________ 59

McLear pegmatite.. 94

Westchester County, Bedford...... 67,68

Reference 

No.

North America........... ........... 14,42,54,92

North Carolina.

General____._________.... 33,46,98 

Ashe County________________ 98 

Avery County.________._____ 98 

Burke County._______________ 98 

Iredell County, Statesville________ 53 

Jackson County, Addie__________ 15,17 

Spruce Pine district..-_____..._... 31,91 

Surry County, Mount Airy________ 83,84

Norway.

Egersund..._____________._.. 82

Oklahoma.

General.. ___...__.... ... 33,53,88 

Wichita Mountains..-___________ 56 

 12,40,87,104

Pennsylvania.

General_______......._-..... 46,97,104

Northampton County______ _____ 59,97

Rhode Island__.....___-__.....--_ 58,88

South Carolina.

General_.______________

Marietta.. ..__ _ .... 

South Dakota.

Keystone...____ ___._...... 31,78

Switzerland.

Glamer____________._-.__ 6

Tennessee.

General-. . . 46,98,104 

Carter County .............. .___ 98

Carthage meteorite_.____...___ 13,16

91

General_______________.__ 34 

Llano County, Baringer Hill......_.... 31,61

United States___ ......... 4,12,44,73,88,92

Utah . . 12

Vermont_.____._..__._. . 53,58

Virginia.

General. . 46,88,98 

Albemarle County ____ 98 

Amherst County__..____ 60 

Austinville district 45 

Culpeper County.-.. 98 

Grayson County _ ____ 98 

Henry County, Chestnut Knob 98

Washington.

General___._______.___.. 12,88,104 

Snoqualmie batholith 53

Wisconsin._. __.................. - 20,46

Wyoming.

General... ... 12 

Pinedale area. 57 

Wheatland area ._ 109 

Wind River Basin_.....__....... - 101

Yellowstone National Park._........... 43,46
URANIUM GEOLOGY OF IGNEOUS AND METAMOEPHIC ROCKS 261

SUBJECTS

Reference 

No.

Age determinations_.__ . 23,31, 

32, 34, 43, 45, 48, 49, 53, 60, 62, 63, 67-69, 74, 

79, 91, 94, 104, 117

Distribution of radioactivity and uranium.... 6,

10, 11, 17, 18, 22, 25, 27, 29, 32, 33, 36, 37, 41,

42, 43, 45, 47, 50, 51, 56, 73, 75, 76, 82, 86, 100

Guide to ore - 28

In the earth__...... .. ! 103

Elements.

Arsenic_______..._____- 102 

Beryllium_________________ 12 

Boron________________ .. 12 

Calcium______...... 3-6,11,54,55

Fluorine_____ . . 12 

Hafnium_____................. _ 64,67

Helium......................... 32,41-43,49,104

Iron.. ...._. ... - 7,17,54

Lanthanum..___-----------_____ 12

Lead . . . - 12,52,67,68,91

Lithium............... ................ 12,78

Magnesium___.__ .. 54,55 

Niobium____. . ... ... 12 

Potassium.................. 2,4,7,9,22,52,55,77

Radium........................... 2,6,7,15-17,

21, 22, 37, 39,40, 43, 49, 51, 83-89,102-104 

Silicon.............................. 22,52,55,81

Sodium______.__.......... ... 3,4

Thorium...... 2, 6, 11, 29, 38, 40, 42, 43, 49, 51,

54, 58, 80, 87, 90, 101, 104, 106, 108 

Tin.......__________.________ 12

Xenon_____.._______........_ 12

Yttrium.................................. 64

Zirconium_________________ 11,12

Geochemistry_.. 2,14,18,26,36,39,46,52,55,90,100

Granitic rocks.'

General.............__... 10, 11, 21, 25, 27, 32,

33, 36, 37, 42, 72,76, 82, 92, 100,104 

Alabama__________________ 98 

Alaska...................... 66,106-108,110-116

Boulder batholith__._____....... 8,50

Boulder Creek batholith............ 27,50,55,81

California_.._......... 27,46,50-52,54,55,81

Canada__________________ 33,46 

Colorado....__________.. 27,50,55,80,81

Connecticut________________ 58 

Eastern United States....___...___. 83,84

Finland......__..____________ 7

France____________________ 82 

Georgia.__._.______ 24,83,84,86,98,105 

Idaho batholith_......_...._.... 27,50,55

Italy__.____.___________ 82 

Lake Superior region___________ 64 

Maine... .....___....... 33,46,71,83,84,86

Maryland____________._____ 83,84 

Massachusetts. _.. . 29,33,38,41,42,46-48,83,84 

Michigan__________________. 64 

Montana_______________ 8,27,50,55 

Nevada.___________________ 

New Hampshire______ 9,27,50,54,55,81,

Reference

Granite rocks Continued No. 

New-Jersey.-. 42,50,81,97

New York....._____.................. 58.70

North Carolina..__.............. 46,83,84,98

Pennsylvania._____._________ 46,97 

Rhode Island_______________ 58 

Sierra Nevada..___................ 27,50,55

South Carolina______________ 98 

Tennessee ____.__________ 46,98 

Texas__________.----.-.---..__ 34

Virginia..____...__.................. 46,98

Wyoming................ ... .... 57,101

Intermediate rocks.

Michigan......__....................... 43,46

New Jersey______.-..__....._ 43,46

New York................................ 46

Wisconsin__________________ 46 

Wyoming .. ....... ... 43,46

Lamprophyres.

Wisconsin_________________ 20 

Leaching.

Laboratory methods. ..... ___ 10,

11, 32, 54,55, 72, 83, 86 

Natural conditions._____ 2,5,14,32,36,80,96

Magmatic differentiation_______ 1-3,9,17,28, 

34, 37, 45, 47, 52, 54, 55, 64, 71, 73, 75, 80, 82, 90

Metamorphic rocks___.__________ 23,25 

Alaska_....__.________.___ 107

Connecticut-_________.......__ 58

Maine___________________ 71 

Massachusetts_..... _____ __ 38,47

New Jersey______._____._ 45,59,97 

New York.___........__.....__ 58,59,70

North Carolina_______________ 98 

Pennsylvania_______________ 59,97 

Rhode Island_______________ 58 

Virginia.-..__..........___......_ 98

Meteorites.

General.............. ......... ... 13,15

Argentina_____________..__ 16 

Arizona.. .__.__ __._ __ 79,87 

Chile.. . . .. 16 

Colorado____.________._____ 16 

Georgia__________________ 16 

Iowa_____________________ 86 

Kansas _...__......_.... 13,16,79,89

Kentucky ___ __ . 16 

New Mexico______..___.. . 16 

Queensland, Australia.._____ _.. 16 

Tennessee________.____..__ 13,16

Minerals.

Allanite ..... .... 9, 11, 14, 27, 31, 35,

60-63, 65, 66, 70, 78, 81, 107-109, 114-116

Amphibole_____._..._______ 42

Anatase.____________._ __ 30

Apatite. ._-__-__-___ .... 5,6,9,

11,14, 33, 39,42, 47, 51, 53, 55, 59, 82, 114

Autunite____________________ 95

Bastnaesite___________ _- 11

Beryl...- . 77
262 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Reference

Minerals Continued No. 

Betaflte.-.. -. -......... ........ 30,78

Beta-uranophane...___________ 24 

Biotite - - ............... 7, 9,

14, 39, 42, 47, 65, 78, 82, 83, 86, 95, 112-114 

Bronzite...--.. -. ..-- ..._.___ 15 

Calcite ............................. 10

Oassiterite.....---_-.-................ 110,115

Chevkinite..----__.------------....-__ 27

Chromite ._...... . --...._-..-.. 15

Clarkeite- - - - - 112 

Columbite____...__...-_______ 78 

Cyrtolite ........................ 30,65,67,68

Diopside..._..--..__.______.__ 15 

Epidote 47,82

Euxenite. 30,69,78,117

Feldspar..... -- 9,42,77,78,82,86,93,95

Fergusonite_____.__________ 31,78 

Fluorite. . 110,116

Garnet . .. .. 43,116

Hematite__________.._______ 112 

Hornblende..__ -. _.. 14

Hydrogoethite. . 66

Ilmenite___----- _-___.____ 29

Kammerite____.___..._____ 17 

Mackintoshite________..____ 31 

Magnetite.---....------.----------.--- 42,43,59

Malachite_________________ 116 

Meta-autunite___ .____.-.__ 8 

Metatorbernite_.._____-__-_ 8

Microlite 19

Molybdenite.--..---.---------------.. 95

Monazite . 14,27,59,69,70,78,106,108, 111 

Muscovite ------------------ 24,78,83,86,93

Olivine -- - _ 15 

Pyrite 95,112

Pyrochlore...- -- - -_-.... 27

Pyroxene______._..________ 42 

Quartz.. ............... 42,77,78,82,86,93,95

Riebeckite________________ 29 

Rutile. 112

Samarskite. ... 31,78,91

Scheelite.... . . . 116

Serpentine__--... .. _...._ 15

Soddyite . 24

11,14,29,33,51,53, 54,66,81,82,106,115,116 

Talc .. 15, 17

Thorite.... - 11,14,27,65

Topaz 110,116

Torbernite .. ._..___.___ 59 

Tremolite._____ _______ 15,17 

Uraninite 23,31,48,65,70,77,78,91,93-95 

Uranophane________. ___ 8,24,95,105 

Urano thorite--..-- - - 115 

Wolframite.---..------------------..-.--- 110

Xenotime.. 14,27,111

Yttrialite - --. - - 31 

Zeolites.. 10,72

Zeunerite.. - -... - - 111 

Zircon. - 2,6,

9, 11, 14, 26, 27, 33, 39, 42, 47, 51, 53, 54, 

56, 59, 64, 66, 70, 74, 81, 82,106, 107, 111, 

114-116

Reference 

No. 

Pegmatites.

General._................. 31,33,36,78,90,100-

Alaska.. _.__... 65,111 

California... . __......___.. 30,35,74

Canada____________________ 33 

Ceylon___________________ 33 

Colorado..... ... 19,31,69,78,95

Connecticut.__...._....._._ 23,31,58,91

Georgia..__.....____________ 24

Maine.. . 71,77 

Massachusetts._ .......___ 31,38,48,63

New Hampshire_____________ 78,93 

New Jersey...___.____._____ 45,59 

New Mexico....- 31,69,78,117

New York. ..... 58,62,67,68,70,94

North Carolina... .- 31,33,91 

Oklahoma_....__._ . ...__.. 33,56

South Carolina__ 33,91 

South Dakota.. 31,78 

Texas-----...---._ _.. 31,61

Virginia___________________ 60> 

Wyoming......_....... ...__....... 109-

Thermoluminescence__________._ 4 

Thorium-uraDium ratio.

General...__.......... ........... 91

In basic rocks......__.________.. 21,44

In granitic rocks-____ - _ . 14,21,44,73,92- 

In intermediate rocks_______.. 14,21.44,92- 

In minerals___________. _____ 33,44 

In volcanic rocks...__ __.__.._.- 1,3,4 

Trace elements in igneous rocks.

Distribution..._____ ........... 75,82-

Ultramafic rocks... 15,16,17,22,37,74

Volcanic rocks.

General.-. - 4,6,27,37,43,88,104 

Alaska..- - - 112-

Arizona...__.__...- .- .. .-.. 12* 

California_................ . ... 1-3,12,21,65

Colorado ----- ... 12,55-

Europe_________.__ ___.. 87" 

Hawaiian Islands______-__._ 85 

Idaho...__....._ ..__ 12,79-

India. - 8T

Japan____.._ .. . 4 

Lassen Volcanic National Park. 1-3,22- 

Massachusetts_______ __.._-. 43 

Michigan 49,102-

Modoclavas_________________ 50,55 

Montana_------ . 121

Nevada._.......... . 12,99

Norway___________.__ - 82- 

Oregon 12,40,87

San Juan lavas.._.__ - 27,55 

Switzerland.. 6-

United States--. - 4,12

Utah__ 12

Washington.._......... . 12

Western United States.. 12 

Wyoming___-_. . 12,101

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