GEOLOGICAL SURVEY CIRCULAR 225 

GEOCHEMICAL ASSOCIATION OF 

NIOBIUM (COLUMBIUM) AND TITANIUM 

AND ITS GEOLOGICAL AND 

ECONOMIC SIGNIFICANCE 

By Michael Fleischer, K. J. Murata, Janet D. Fletcher, and Perry F. Narten 

UNITED STATES DEPARTMENT OF THE INTERIOR 

Oscar L. Chapman, Secretary 

GEOLOGICAL SURVEY 

W. E. Wrather, Director 

GEOLOGICAL SURVEY CIRCULAR 225 

GEOCHEMICAL ASSOCIATION OF NIOBIUM (COLUMBIUM) AND TITANIUM 

AND ITS GEOLOGICAL AND ECONOMIC SIGNIFICANCE 

By Michael Fleischer, K. J. Murata, Janet D. Fletcher, and Perry F. Narten 

Washington, D. C.,1952 

Free on application to the Geological Survey, Washington 25, D. C. 

GEOCHEMICAL ASSOCIATION OF NIOBIUM (COLUMBIUM) AND TITANIUM 

AND ITS GEOLOGICAL AND ECONOMIC SIGNIFICANCE 

CONTENTS 

Page 

Abstract..................................... 1 

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 

A cknowlE:dgments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 

General geochemical considerations. . . . . . . . . . . 2 

Method of spectrographic analysis . . . . . . . . . . . . . 2 

Experimental results . . . . . . . . . . . . . . . . . . . . . . . . . 3 

Niobium in igneous rocks. . . . . . . . . . . . . . . . . 3 

TABLES 

Page 

Experimental results--Continued 

Niobium in bauxite. . . . . . . . . . . . . . . . . . . . . . 3 

Niobium in byproducts of bauxite plants..... 7 

Niobium in titanium minerals. . . . . . . . . . . . . 8 

Possibility of recovery of niobium from Arkansas 

bauxite and from titanium minerals. . . . . . . . . . . . 8 

Literature cited........ . . . . . . . . . . . . . . . . . . . . . . 9 

Page 

Table l. Niobium contentofrocks reported to contain 0.01 percent or more Nb ............................... 4 

2. Niobium content of Arkansas bauxites ....•...................•.........•.....•..•.•. , . . . . . . . . ... 5 

3. Niobium content of products of bauxite treatment at the Hurricane Creek plant, 

R.eynolds Metal Co. . . . . . . . . . . . . . . . . . . . . • . • . . . . . . . . . . . . . . . . . • . • . . • . . . . . . . . . . . . • . . . . . . . . . . . . . . . . 7 

4, Analyses of titanium- and iron-rich concentrates from black sands from the Hurricane Creek 

plant, Reynolds Metal Co. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • • . . . . . . . . • . . . . . . . . . . . . . . . . 8 

5 .. Analyses of fractions of Ti-rich concentrate..... . • • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . ...•. 8 

6. Analyses of fractions of a black sand from bauxite. . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . 9 

7. Analyses of fractions of black sand from Wilfley table........... . . . . . . . • . . . . . . . . . . • . . . . . . . . . . .. 9 

8. Niobium content of titanium minerals. . . • . . . . . . . . • . . . . . . • . . . . . . . . . . . . . ........................... 11 

ABSTRACT 

Niobium in rocks occurs in highest concentrations 

in granitic pegmatites and in alkalic rocks such as the 

nepheline syenites. It occurs commonly as a substituent in titanium minerals. Weathering of alkalic 

rocks produces bauxite enriched in niobium. Analyses 

show bauxite from Arkansas to contain an average of 

0.05 percent Nb. The niobium present in the Arkansas 

bauxite processed annually is equal in amount to about 

80 percent of that imported annually by the United 

States. Fractionation of black sand from Arkansas 

bauxite shows the niobium to be concentrated chiefly 

in an ilmenite fraction containing more than 40 percent 

Ti02 and as much as 0.86 percent Nb. 

Analyses of titanium minerals from many 

sources show the presence of niobium, the amount 

present varying with the type of rock in which the 

minerals occur. Minerals from alkalic rocks and 

from granitic pegmatites are highest in niobium content. 

Metallurgical research is needed, especially on 

the possibility of recovering ni:::bium and titanium from 

chlorination processes. 

INTRODUCTION 

Niobium (columbium) has recently become important in the manufacture of certain high-temperature 

and non-creep steels. The United States imported 

1 

more than 1-1/2 million pounds of niobium ore (concentrates) in 1949 (Clark, 1951); 1 domestic production was very small. The world production has 

come from granitic pegmatites and as a byproduct of 

the recovery of cassiterite from placers derived 

from granitic rocks. 

Early in 1951 the Geological Survey undertook a 

search for new sources of niobium. Fortunately the 

general pattern of the geochemical behavior of 

niobium was fairly well known from an earlier summary of the literature (Fleischer and Harder, 1945) 

and from the comprehensive researches of Rankama 

(1948). From these it was possible to select for 

further study several types of material in which 

niobium might be present in concentrations sufficient 

to make .them of interest as source materials. 

Those selected as the most promising types of 

mater:al were (1) alkalic rocks, especially nepheline 

syemtes; (2) bauxites derived from alkalic rocks; 

(3) titanium minerals and ores; (4) zirconium minerals 

and ores; (5) tungsten minerals and ores; and (6) tin 

minerals and ores. The present report is a preliminary account of work on the first three. Niobium has 

been found m concentraticns sufficiently high to 

justify research on the metallurgical processes for 

its separatwn and recovery. The search for new 

sources of niobium will be continued, and it is hoped 

that this report will st:mulate others to begin the 

required metallurgical research. 1See Literature cited 
ACKNOWLEDGMENTS 

We are indebted to our colleagues M. K. Carron, 

J. I. Dinnin, and Leonard Shapiro, who made chemical analyses; Elizabeth L. Hufschmidt, J. C. Rabbitt, 

and H. J. Rose, Jr., who made spectrographic 

analyses; and Jewell J. Glass and Marie L. Lindberg, 

who made mineralogical separations. R. P. Bryson, 

E. P. Kaiser, J. J. Norton, and W. T. Pecora, of 

the Geological Survey, contributed advice as to the 

selection of samples for analysis. 

Samples for analysis were contributed by the 

following companies, who kindly granted permission 

to publish the results obtained. Alcoa Mining Co., 

American Cyanamid Co., Dulin Bauxite Co., Consolidated Chemical Industries, Dulin Bauxite Co., 

E. I. duPont de Nemours Co., The Glidden Co., 

National Lead Co., New Jersey Zinc Co., and 

Ventures, Ltd. 

CENERAL GEOCHEMICAL CONSIDERATIONS 

Niobium is a chemical element with atomic 

number 41 and atomic weight 92.91. It belongs to the 

fifth group of the periodic table and is quinquevalent 

in most of its compounds. Niobium is a rare element; 

Rankama ( 1948, pp. 48 -52) estimates its abundance 

in igneous rocks to be 0.0024 percent, which would 

make it about thirty-first in abundance of the elements. 

The empirical ionic radius of niobium is given 

as 0. 69A. (Ahrens, 1952), not very different from 

those of magnesium (0.66A.) and ferrous iron (0. 74A. ). 

The valence of niobium, however, is so much higher 

that one would expect that magnesium and iron 

minerals formed in the early stages of magmatic 

crystallization would not contain much niobium. This 

expectation has been verified experimentally. As 

crystallization of igneous rocks proceeds, niobium is 

perferentially concentrated in the residual magmas 

as shown by Goldschmidt (1937) and by Rankama 

(1948). According to Rankama, the igneous rocks of 

highest niobium content are the granites (0.0021 percent), the syenites (0.0035 percent), and the nepheline 

syenites (0.031 percent). Of all igneous rocks, therefore, the nepheline syenites and similar alkalic rocks 

cohtain more than 10 times the concentration of other 

rocks and appear to be the most promising for further 

study. 

Goldschmidt (1937, p. 667) points out that 

niobium would be expected, considering its ionic 

potential, to be concentrated during weathering processes; he states that for bauxite the factor of concentration is 4 to 5 as compared with the parent rock. 

Because the nephelme syenites are rocks high in niobium, bauxites derived from them should be particularly 

rich in niobium. This has now been tested and verified in the laboratory of the Geological Survey and 

a summary of the results on Arkansas bauxites has 

been published in a recent paper (Gordon and Murata, 

1952). The study is being pursued further, particularly 

to learn the mode of occurrence of the niobium and its 

distribution in the bauxite district and among the 

minerals of the bauxite.· 

One would expect that niobium would occur as 

a substituent for elements of high valence having ionic 

radii close to 0. 60A.' These include quinquevalent 

2 

Ta (0.68A.), quadrivalent Ti (0.68A.), Zr (0.79A.), 

Sn (0. 71A.), and Mo (0.62A.), and sexivalent 

W (0.62A.) .. This is confirmed by experimental data 

except for molybdenum. The very close association 

of niobium and tantalum is well known. Rankama 

(1948, pp. 48-52) points out that these elements are 

separable in nature and that the Nb:Ta ratio, which 

averages 11.4, is very much higher (384) in nepheline 

syenites. The association of niobium with titanium 

has been shown by the work of Hevesy, Alexander, and 

Wurstlin (1929), Kunitz (1936), Borowsky and Blochin 

(1937), Panteleleev (1938), and Rankama (1948). The 

niobium content of titanium minerals, with part.icular 

attention to their geological environment, is also 

under investigation in the Geological Survey laboratories. A summary of the results up to now, including 

data from the literature, is given below. Studies of 

the association of niobium with tungsten, tin, zirconium, 

and molybdenum will be reported later. 

METHOD OF SPECTROGRAPHIC ANALYSIS 

The spectrographic analyses were made under 

the following conditions: 

Excitation: 220-volt ballasted d-e arc, run at 15.5 a. 

Arc gap maintained at 3.5 mm throughout the burning period. Arc image 

focussed on the slit at 5. 5 magnification, 

and light from the central 2 mm part 

allowed to enter the spectrograph. 

Spectrograph: Wadsworth-mounting type of grating 

spectrograph with dispersion of 5A/mm 

in the first order. 

Wavelength range covered: 2,230 - 4, 730A in the 

first order. Such a wide range is unnecessary for analyses solely for Nb, but 

was recorded so that the spectrograms 

would be available for future study of 

other elements. 

Electrodes: High-purity graphite rods, 1/4 in. 

diameter, with thin-walled cavity as described by Myers (1951); used as the 

anode. 

Plate: Eastman III-0, developed at 20°C for 5 min 

in DK-50 developer. 

Plate calibration: Method of Dieke and Crosswhite 

(1943). Iron lines present in spectra of 

a quartz-microcline mixture containing 

1 percent Fe203 (matrix of comparison 

standards) were used. 

Microphotometer: Projection comparator-microphotometer employing a scanning slit at 

the plate. 

Nb lines used: 3163.40 anr:l 3194.98A. Limit of detection, 0.01 percent in the samples as 

analyzed. 

Analytical curves were established by means 

of a set of standards containing known concentrations 

of Nb205 and Ta205 (high-purity oxides) in a matrix 

consisting of 60 parts of quartz, 40parts ofmicrocline, 

and 1 part of Fe203, 25-mg portions being arced to 
completion. The standards were made by successive 

dilutions to contain 1.00, 0.464, 0.215, 0.100, 0.0464, 

0.0215 ..... 0.00100 percent Nb and Ta. No internal 

standard was used. The quartz-f~ldspar-iron oxide 

matrix will hereafter be referred to as the pegmatite 

base. 

All rocks and minerals were first crushed, quartered, and ground in agate mortars to pass 150-mesh silk 

bolting cloth. Bauxites and clays were then ignited at 

900° C and the loss in weight noted so that the final percentage ofNb could be calculated to the original, unignited state. 

In order to analyze materials of greatly different 

chemical composition by means of the pegmatite-base 

standards, the samples were further treated in such 

a way as to make their composition more nearly that 

of the standards. Igneous rocks were mixed with onehalf their weight of pure quartz. All other materials 

were mixed with an equal weight of a powder composed 

of 95 percent quartz and 5 percent Na2C03. 

The prepared samples were then analyzed by 

arcing to completion duplicate 25-mg portions. All 

samples showing 0. 05 percent or more of Nb were 

next diluted with sufficient pegmatite base so that their 

reanalysis would be done at a concentration level of 

about 0.015 percent Nb. This practice resulted in 

greater accuracy for samples high in Nb because these 

(in the diluted state) closely approached the comparison 

standards in composition. As a test of the reproducibility of the method, a number of samples were 

analyzed in duplicate on several plates on different 

days. Considering the mean of the duplicate on each 

plate as a determination, the results were within ± 

10 percent of the average of all determinations. 

To date, only a few samples have been analyzed 

chemically, and we are indebted to J. I. Dinnin and 

M. K. Carron, of the Geological Survey, for the 

chemical results tabulated below. 

Percent Nb 

Spectrographic Chemical 

Bauxite-----------

Bauxite-----------

Brookite----------

Wolframite-------

Lepidolite---------

0.053 

. 050 

2.4 

1.3 

1.1 

EXPERIMENTAL RESULTS 

Niobium in igneous rocks 

0.05 

. 03 

2. 7 

1.2 

1. 2 

T~e average content of niobium in various types 

of igneous rocks was determined by Rankama ( 1948) by 

the analysis of 78 samples with the following results: 

Anorthosites and dunites----------

Diorites------------------------

Eclogites-----------------------

Basic alkalic rocks--------------

Ultrabasic rocks-----------------

Gabbros------------------------

Granites-----------------------

Syenites------------------------

Nepheline syenites---------------

Percent Nb 

(average) 

0.00003 

. 0004 

. 0004 

. 0014 

. 0016 

. 0019 

. 0021 

. 0035 

. 031 

3 

Our studies have confirmed the relatively high 

niobium content of nepheline syenites and related 

rocks and have shown that high niobium content is 

particula:i-ly characteristic of those alkalic rocks with 

which are associated the remarkable masses of 

crystalline CaC03 generally referred to as 

"carbonatites." As further study of these rocks, 

particularly of the mode of occurrence of the niobium 

in them, is under way, we shall reserve detailed 

discussion and merely present the data available on 

all rocks that have been reported to contain as much 

as 0.01 percent Nb. These data are assembled in 

table 1. Nearly all the 52 rocks listed are nepheline 

syenites or related rocks, with only a few rocks of 

granitic composition and a few mafic rocks that are 

associated with alkalic rocks. No quantitative data 

are yet available on the distribution of niobium among 

the minerals of these rocks, although it is known that 

the niobium is largely concentrated in such titanium 

minerals as rutile, ilmenite, perovskite, and sphene. 

Analyses of these minerals separated from the abovementioned or from similar rocks are listed in table 8 

and are discussed below under the heading "Niobium 

content of titanium minerals. " Part of the niobium in 

some of these rocks is present in zirconium minerals 

such as zircon, eudialyte, and catapleiite, and 

part is in some rocks as the niobium minerals 

pyrochlore (alkalic rocks) and columbite or microlite 

(granitic rocks). 

Niobium in bauxites 

We have extended the work of Gordon and 

Murata (1952), whose analyses of 14 bauxites and 

bauxitic clays from Arkansas showed a minimum 

content of 0.02 percent Nb, a maximum content of 

0.1 percent Nb, and an average content of 0.05 percent Nb. Table 2 lists these analyses and those of 

32 additional samples which confirm the earlier results. 

Further work is in progress to determine how the 

niobium content varies in different parts and types of 

bauxite deposits in Arkansas and to determine the distribution of niobium among the minerals of the bauxite. 

Analyses have also been made by the 

Geological Survey of many samples of bauxite 

derived from rocks other than alkalic rocks, 

including material derived from basaltic rocks, 

gneisses, and limestones. These samples have 

rnuch lower contents of niobium; none was found 

that contained as much as 0.01 percent Nb. The 

samples include 5 lateritic bauxites from Oregon, 

collected by J. W. Hosterman; 28 high-alumina 

clays from Idaho and Washington, collected by 

I. G. Sohn and J. W. Hosterman; 3 bauxites from 

Surinam, Dutch Guiana, kindly furnished by 

Aluminum Co. of America and American Cyanamid 

Co. ; and 1 bauxite from Berbice, British Guiana, 

kindly furnished by American Cyanamid Co. 

Rankama (1948) reports 0.004 percent Nb in 

bauxites from Melegesbanya, near Gant, Hungary, 

and from Rock Run, Ala. It is of interest to 

note (table 3) that samples of red mud from 

treatment of Surinam and Jamaica bauxites both 

contained 0.02 percent Nb, which suggests that 

these bauxites contain some thousandths of a 

percent of Nb. 

We hope to analyze bauxites which are from 

localities, other than Arkansas, where the bauxite 
l 

2 

3 

4 

5 

6 

7 

8 

9 

10 

ll 

12 

13 

14 

15 

16 ~ 17 

18 

19 

~able 1.--Niobium content of rocks reported to contain 0.01 percent or more Nb 

Number of 

Locality samples Percent Nb 

I Arkansas: Pulaski and 9 0.016-0.035 

Saline Counties. 

Arkansas, Sal1ne CountY------ l . 04 

Arkansas, Magnet Cove------- 5 .02-.06 

Arkansas, Potash Sulfur 6 { .os, .15, .Z/ 

Springs. 

1.6, 2.7, 3.0 

Colorado, Iron Hill-------- ll .ox 

Idaho, Lemhi CountY--------- 2 .01, .03 

New Hampshire, Bartlett------ l .02 

New Jersey, Beemerville------ l .01 

New Mexico, Wind Mountains--- l .02 

----do------------------------ l .34 

New Mexico, Black Mountains-- l .03 

New Mexico, Jemez Mountains-- 2 .01 

Texas, Sierra Diablo-------- 4 .05-.2 

Greenland, Julienahaab dist.- 2 a.32, .21 

Sweden, Gellaberg, Sk£ne----- l .017 

Germany, Hammer------------- l .02 

Portugal, Serrade Monchique-- l . 04 

U.S.S.R., Mariupol dist.----- 7 .02- .. 08 

U.S.S.R., Kola Peninsula----- l .11 

~e accuracy of these old chemical analyses is questionable~ 

Type of rock Collector 

Nepheline syenite----- M. Gordon, 

R. P. Bryson . 

Tinguaite dike------- W. T. Holser----

Alkalic rocks-------- W. T. Pecora----

----do-----------------1} W. T. Pecora, 

E. Ingerson. 

Altered alkalic rocksAlkalic rocks-------- V. R. Wilmarth---

Granite pegmatite----- W. A. Roberts---

Granite------------- W. T. Holser----

Nepheline syenite----- ------do----------

----do----------------- ------do-~--------

Eudialyte syenite------ ------do----------

Nepheline syenite----- ------do----------

Rhyolites------------ C. S. Ross------

Alkalic rocks-------- A. Slaughter----

Nepheline syenite------ ----------------- Feldspar basalt------- --------------- Phonolite------------ ---------------

Nepheline syenite----- --------------- ----do----------------- --------------- Titanomagnetite --------------- olivinite. 

Analyst 

K. J. Murata, 

H. J. Rose, Jr. 

K. J. Murata. 

K. J. Murata, 

H. J. Rose, Jr. 

J. D. Fletcher, 

K. J. Murata. 

J. D. Fletcher. 

H. J. Rose, Jr. 

K. J. Murata. 

Do. 

Do. 

Do. 

Do. 

Do. 

J. C. Rabbitt. 

Us sing ( 1912) . Rankama ( 1948) . Do. 

Rankama ( 1948) • Morozewicz (1930). 

Rankama (1948). 
Table 2 --Niobium content of Arkansas bauxite 

Sample no. Percent Nb Collector Analyst 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46 

0.02 

.04 

• 050 

.06 

.03 

. 02 

.04 

. 053 

.07 

.04 

.1 

.02 

.02 

.08 

.085 

.028 

.048 

. 033 

.04 

. 051 

.047 

. 045 

. 051 

.051 

. 049 

. 05 

.055 

.036 

. 03 

. 03 

.04 

.082 

. 050 

. 03 

.04 

.02 

. 02 

. 02 

.034 

.043 

.054 

.057 

M. Gordon-------------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do-------------- ------ -----do---------------------

-----do-------~-------------

-----do-------------------

-----do------------------- - W. R. Griffitts-------------

R. P. Bryson --- ----------- J. I. Tracey, Jr.-----------

M. Gordon---- ------------- ----do------------------ -- ----do------------------

----do---------------------

Alcoa, Hurricane Creek------

Reynolds Metal Co., 

Hurricane Creek. 

R. P. Bryson----------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do------------------- - -----do------------ -------- -----do---------------------

-----do---------------------

-----do---------------------

-----do---------------------

-----do----------------------

K. 

J • 

J. 

Do. 

Do . Do. 

Do. 

Do • Do. 

Do • Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do . Do. 

D. 

Do . Do. 

Do • Do • Do. 

Murata. 

Fletcher. 

K. J. Murata • H. J. Rose and 

E. H Hufschmid t. 

Do. 

Do • Do • Do. 

Do. 

Do • Do . Do. 

Do. 

Do • Do . Do. 

Do. 

Do. 

H. J. Rose and 

E. H Hufschmidt. 

.057 -----do--------------------- Do. 

.034 -----do--------------------- Do. 

.067 -----do--------------------- Do. 

050 -----do--------------------- Do. 

Average, 46 

Average, 39 

Average, 7 

samples---- --------------------------------------------------------------------0.0~5 

individual samples----------------------------~~-------------------------------- .044 

composite samples (nos. 20-25, 46)---------------------------------------------- .049 

Descriptions of samples: 

l. 

2. 

3. 

4. 

5. 

Dark reddish-brown to black bauxite pebbles filling channels in the lower bauxite bed in 

the Fletcher mine of Reynolds Mining Corp. in the W~SEiSWi sec. 11, T. 2 S., R. 14 W., 

Saline County. 

Oxidized ferruginous granitic-textured bauxite from a weathered outcrop in the Pruden 

mine, Alcoa Mining Co., NEtSWi sec. 16,. T. 2 S., R. 14 W., Saline County. 

Red bauxite with black pisolites ("birds-eye ore") from mining face in the west part of 

the Section 16 mine, Alcoa Mining Co., SEiSWi sec. 16, T. 2 S., R. 14 W , Saline County. 

Grs.ni tic-textured bauxite (1' sponge ore") block from along company road in Middle Maud 

mine, Alcoa Mining Co., in SWiSEt sec. 22, T. 2 S., R. 14 W., Saline County. 

Poorly pisolitic bauxite containing fine siderite, from U. S. Bur. Mines drill hole 3-019, 

depth 267 feet, South Ironton deposit, W.A. Dreher property, in the NWiSEi sec. 14, T. 

1 S., R. 12 W., near Ironton, Pulaski County. 

5 
Descriptions of samples, table 2--Continued 

6. Pisolitic bauxite hardcap with fluid pisolites from U. S. Bur. Mines drill hole 6-1278, 

depth 278 feet, Bates deposit, in the NWtNEt sec. 21, T. l S., R. 12 W., Pulaski County. 7. Pisolitic bauxite cut by a vein of crystalline siderite in U. S. Bur. Mines drill hole 

16-048, depth 455.2 feet, in the East Bauxite deposit, International Paper Co. property, 

in the SEt sec. 31, T. 2 S., R. 13 W., Saline County. 

8. Poorly pisolitic bauxite containing siderite and chlorite, from U. S. Bur. Mines drill 

hole 16-052,. depth 473.0 to 473.1 'feet, East Bauxite deposit, International Paper Co. 

property, SEt sec. 31, T. 2 S., R. 14 W., Saline County. 

9. Poorly pisolitic siliceous bauxite from U. s. Bur. Mines drill hole 16-052, depth 451.9 

to 452.2 feet. 

10. Tannish-gray bauxitic underclay from U. S. Bur. Mines drill hole 16-052, depth 480.5 

to 480.6 feet. 

ll. 

12. 

13. 

14. 

15. 

16. 

17. 

18. 

19. 

20. 

21. 

22. 

23. 

24. 

25. 

26. 

27. 

28. 

29. 

30. 

31. 

32. 

33. 

34. 

35. 

36. 

37. 

38. 

39. 

40. 

41. 

42. 

43. 

44. 

45. 

46. 

Fragmental kaolinitic underclay from U. S. Bur. Mines drill hole 16-052, depth 488 feet. 

Type III b~uxite deposit. Transported pebbly bauxite with gibbsitic to kaolinitic matrix, 

from east face of the Harley pit mine of Dulin Bauxite Co., SEtSEt, sec. 24, T. l N., R. 

12 W., Pulaski County. 

Type III bauxite deposit. Cross-bedded bauxite from ore body in Reichart shaft mine, 

NWtSWt, sec. 2, T. l S., R. 12 W., Pulaski County. 

Type IV bauxite deposit. Transported light-tan bauxite rubble, at or near top of upper 

bauxite bed, near middle of west wall of the Midwest Pit mine of Midwest Mines Co. in 

the E~NEtNEt, sec. 24, T. 2 S., R. 14 W., Saline County. 

Harris deposits near Bryant. 

Ratcliffe mine, Pulaski County. 

Stuckey pit at Bauxite. 

Section 26 mine near Bauxite. 

Hurricane Creek plant. 

Reynolds. Month-end composite, July, August, September 1947. 

Reynolds" Month-end composite, June, July, August 1948. 

Reynolds. Month-end October 1949. 

Reynolds. Month-end April 1950. 

Reynolds. Month-end April 1951. 

Reynolds. Month-end November 1951. 

Reynolds. Bauxite from Hurricane Creek plant. 

Bauxitic clay (from Consolidated Chemical Industries plant stockpile), Bierman mine, 

Pulaski County. 

Bauxite (from plant stockpile), Bierman mine. 

Bauxite. Monthly composite, Berry-Mayhan mine; SWtNEt, sec., 2, T. l S., R. 12 W., 

Pulaski County. American Cyanamid Co., Berger Plant. 

Bauxite, low-iron type (raw composite) Dan Rauch mine, SEtNEt, sec. 9, T. l S., R. 12 W., 

Pulaski County. American Cyanamid Co. 

Bauxite, calcined product from blend of bauxite, Dixie mine, SWtSWt,sec. 36, T. lN., R. 

12 W., Pulaski County, and BC-400 mine, SEtNWt, sec. 31, T. 2 S., R. 13 W., Saline County. 

Dulin Bauxite Co. 

Bauxite, high organic content typical; part granitic and part pisolitic. Bertha Extn. 

mine, SEt, sec. 27, T. 2 S., R. 14 W., Saline County. Alcoa Mining Co. 

Bauxite, granitic, grab sample from conveyor belt. Nielson Underground·mine, NWtNWt, sec. 26, T. 2 &, R. 14 W., Saline County. Alcoa Mining Co. 

Bauxite, grab sample by shaft, BC-400mine, SEtNWt, sec. 31, T. 2 S., R. 13 W., Saline 

County. Dulin Bauxite Co. 

Bauxite(?) from thin bed in Wilcox formation (core sample), middle of sec. 28, T. 2 S., 

R. 14 W., Saline County. Alcoa Mining Co. 

Bauxite, auger drill sample, upper 6 feet; Lewis mine, NWtNWt, sec. 9, T. l S., R. 12 W., 

Pulaski County. American Cyanamid Co. 

Bauxite, auger drill sample, 6 to 12 feet; Lewis mine,NWtNWt, sec. 9, T. l S., R. 12 W., 

Pulaski County. American Cyanamid Co. 

Bauxite, auger drill sample, 12 to 18 feet; Lewis mine, NWtNWt, sec. 9, T. l S., R. 12 W., 

Pulaski County. American Cyanamid Co. 

Bauxite, daily mine production. Harris mine, NEtNWt, sec. 36, T. l S., R. 14 W., 

Saline County. Reynolds Mining Co. 12-13-51. 

Bauxite, daily mine production. Harris mine, NEtNWi-, sec. 36, T. l S., R. 14 W., 

Saline County. Reynolds Mining Co. 12-14-51. 

Bauxite, daile mine production. Harris mine, NEtNWt, ~ec. 36, T. l S., R. 14 W., 

Saline County. Reynolds Mining Co. '12-19-51. 

Bauxite, daily mine production. Harris mine, NEtNWt, sec. 36, T. l S., R. 14 W., 

Saline County. Reynolds Mining Co. 12-30-51. 

Bauxite, daily mine production. Harris mine, NEtNWt, sec. 36, T. l S., R. 14 W., 

Saline County. Reynolds Mining Co. 12-31-51. 

Bauxite, daily mine production (12-31-51), Bray mine, sec. 35, T. 1 S., R. 14 W., 

Saline County. Reynolds Mining Co. 

Bauxitic clay, one-day withdrawal (12-19-51). Elrod-Harris low-grade pile, sec. 35, T. 

1 S., R. 14 W., Saline County, Reynolds Mining Co. 

Bauxite. Monthly composite for January, 1952, metal-grade shipments by Alcoa from Arkansas. 

6 
has been derived from alkalic rocks and which may 

therefore be expected to be high ·in niobium content. 

Among such localities are the following: 

Po~os da Caldas, Minas Gerais, Brazil. 

Ile de Los, French Guinea, French WestAfrica. 

Gold Coast, western Africa. 

Niobium in byproducts of bauxite plants 

As stated previously, no data are yet available 

as to the distribution of niobium among the minerals 

present in bauxite. However, it is highly improbable 

from geochemical considerations that it is present in 

high concentrations as a substituent in the aluminum 

oxide hydrates or ferric oxide hydrates that constitute the bulk of bauxite ore. Rather, niobium would be 

expected to be present in solid solution in the 

tatanium and zirconium minerals. If this is correct, 

it might reasonably be expected that niobium could 

be concentrated in some stage of the-chemical processing of bauxite ore. 

In brief, the treatment of bauxite 1 as carried 

out at the Hurricane Creek, Ark. plant of the 

Reynolds Metal Co., is as follows: The bauxite is 

digested in hot sodium hydroxide solution. The 

insoluble material is separated from it as coarse 

material ("black sand") and fine material ("red mud"). 

From the solution, A 1203. 3H20 is crystallized, 

leaving "spent liquor. " The black sand is discharged 

into a special tailings pond. The red mud is mixed 

with CaC03 plus Na2C03 and sintered, after which 

it is leached to recover more alumina. The leached 

residue ("brown mud") is discharged into a tailings 

pond. 

By analyzing samples obtained through the 

courtesy of Mr. W. W. Binford, superintendent of 

the Hurricane Creek plant of the Reynolds Metal Co., 

we have been able to follow the course of the niobium 

during the process. The analytical data are given 

in table 3; they show that niobium is concentrated in 

the material that is insoluble in NaOH solution. 

The brown mud, although its niobium content is 

slightly higher than that of the black sand, is not a 

very attractive material on which to attempt further 

concentration because the material is so fine-grained. 

Work so far has therefore been confined to the black 

sand. A study by the U. S. Bureau of Mines 

(Calhoun, 1950) showed that titanium-rich and ironrich concentrates could be prepared by tabling and 

by magnetic separation. The data on these concentrates are given in table 4. Through the courtesy of 

Mr. Binford, samples of these concentrates were 

obtained by the Geological Survey and analyses for 

niobium are given in table 4. 

The titanium-rich concentrate was further 

purified in our laboratory by Miss Jewell J. Glass 

by means of magnetic and heavy-mineral separations. 

Data on the fractions obtained, given in table 5, show 

that the niobium content can be raised to over 0. 8 

percent. It is hoped that further work will permit 

the analysis of the individual pure minerals. 

As a check, a black sand (No. 12 of table 3) 

was subjected to heavy-mineral and magnetic separations. The procedure was as follows: Approximately 

300 grams·was crushed to pass 80-mesh. The material passing 270-mesh was not investigated further. 

The portion passing 80-mesh and retained on 270-mesh 

was separated twice in methylene iodide (spgr 3.2). 

The heavy fraction was then divided into the following 

magnetic fractions: Magnetic to the hand magnet, magneticatO.l, 0. 2, 0. 3, andO. 5arnperes andnonrnagnetic 

at 0. 5 amperes at a slope of 20° towards the nonmagnetic 

side of a Franz Isodynamic Separator. The results,gi ven 

in table 6, agree in general with those of tables 4 and 5. 

Comparable products from the East St. Louis, 

Ill. , plant of the Aluminum Company of America 

have not been studied. However, we have fractionated 

Table 3.--Niobium content of products of treatment of Arkansas bauxitea at the Hurricane 

Creek plant, Reynolds Metal Co. 

No. 

l 

2 

3 

4 

5 

6 

7 

8 

9 

10 

ll 

12 

13 

14 

15 

16 

17 

Product 

Al203.3H20----------------------------

Calcined alumina----------------------

Spent liquor--------------------------

Sinter filtrate-----------------------

Red mud-------------------------------

Brown mud-----------------------------

-----do--------------------------------

-----do--------------------------------

-----do--------------------------------

Sinter residue------------------------

Black sand---------------------------- -----do--------------------~-----------

-----do--------------------------------

-----do--------------------------------

-----do--------------------------------

-----do--------------------------------

-----do--------------------------------

Percent Nb 

<0.01 

< .01 < .01 

< .01 

.08 

. 07 

.076 

.069 

. 073 

. 09 

.06 

. 064 

. 062 

. 052 

.048 

.048 

.052 

Analyst 

K. J. Murata 

Do. 

Do. 

Do. 

Do. 

Do . Do. 

Do. 

Do . Do • 

Do • H.·J. Rose, Jr • Do. 

Do • Do. 

Do. 

Do. 

aSamples of red mud from treatment of Surinam and Jamaica bauxite each contained 0.02 percent Nb. 

7 
Table 4.--Analyses o~ titanium- and iron-rich concentrates ~rom black sands ~rom the Hurricane 

Creek plant, Reynolds Metal Co. 

Ti Concentratel Fe Concentrate2 Ti Concentratel Fe Concentrate2 

(a) (b) (a) (a) (b) (a) 

Ti02---------- 41.2 39-9 8.0 CaO----------- 0.6 --- 0.5 

Fe------------ 20.1 19.9 46.5 Ignition loss- 2.2 --- 12.2 

Mn------------ 8.9 --- --- Al2-03--------- 9.4 --- 8.9 Percent Nb---- 30.67 --- 3o.032 

Si02---------- 2.6 --- 1.4 

a. Mter Calhoun (1950). Analysis by U. S. Bureau o~ Mines. 

b. Leonard Shapiro, U. S. Geol. Survey, analyst. 

lThis concentrate was 3.4 percent by weight o~ the black sand. 

2This concentrate was 4.5 pe~cent by weight o~ the black sand. ~- J. Rose, Jr. and Janet D. Fletcher, U. S. Geol. Survey, analysts. 

a black sand kindly furnished by Mr. Laurence 

Litchfield of Alcoa Mining Co. This was produced 

from an experimental Wilfley-table installation later 

discontinued (letter from Laurence Litchfield to 

M. Fleischer, January 21, 1952). Analyses on the 

fractions, given in table 7, show that the material is 

similar to the titanium-rich concentrate from the 

Hurricane Creek plant (table 5) except that it contains 

much siderite and little magnetite. 

Niobium in titanium minerals 

Although the geochemical association of niobium 

with titanium has long been recngnized and many 

analyses of titanium minerals in the literature show 

appreciable niobium contents, little attention has been 

paid to the variation of niobium content with the type 

of rock in which the titanium minerals occur. Determmations of the niobium content of the common 

titanium minerals are assembled in table 8, omitting 

only the rarer s:licates. Data on the latter are given 

by Fleischer and Harder (1945) and byRankama (1948) 

Many more analyses are needed on material of 

known paragenesis, but a few generalizations can be 

made from the data in table 8. It seems clear that 

minerals from alkalic rocks and from graniti.c pegmatites are highest in niobium and that those associated with anorthosites and gabbros are lowest. This 

is shown best by the data for ilmenite. The largest 

masses of titanium-rich rocks, such as the huge 

ilmenite-magnetite deposits associated with the 

anorthosite-gabbro of the Adirondacks and Quebec, 

are very low in niobium content; the ilmenite from the 

beach sands of Florida and India, presumably derived 

from crystalline rocks, have Nb contents ranging from 

0. 04 to 0. 40 percent; and ilmenite from alkalic rocks 

is highest (up to 0.9 percent). 

The few data available in table 8 imiicate that 

when rutile and ilmenite occur together, rutile generally has the higher niobium content. Of the 35 rutile 

samples listed in table 8, 12 have Nb contents more 

than 1 percent. Most rutile, however, will probably 

be found to contain 0.05 to 0.3 percent Nb, with 

samples of higher Nb content found in granitic pegmatites and alkalic rocks. 

The 20 perovskite analyses listed in table 8 include 13 or 14 from alkalic rocks. Those highest in 

niobium occur in carbonatites associated with alkalic 

rocks. 

POSSIBILITY OF RECOVERY OF NIOBIUM FROM 

ARKANSAS BAUXITE AND FROM 

TITANIUM MINERALS 

The data reported as the result of this work 

suggest the possibility that niobium may be obtained 

from three sources not now utilized: 

1. As a byproduct from Arkansas bauxite. 

2. From titanium minerals used in the manufacture of titanium metal. 

3. From titanium minerals from alkalic 

rocks such as the carbonatites. 

Table 5.--Analyses o~ ~ractions o~ titanium-rich concentrate re~erred to in table 4 

[Separations' by Jewell } • Glass] 

Percent o~ total 

Original titanium-rich concentrate-- 100 

Fractions: 

Magnetite------------------------- 12.4 

Calcite and quartz---------------- 10.5 

Ilmenite plus limonite------------ 73-3 

Mainly zircon, with some rutile, 3.8 

s·phene, ilmenite. 

100.0 

aspectrographic analyses by Janet D. Fletcher. 

bchemical analyses by Leonard Shapiro. 

CNot determined. 

8 

Percent Nba Percent Ti02b 

0.67 39-9 

.026 1.3 

(c) --- . 79-.86 46-50 

.87 36 t' ., 

--- ---
Table 6.--Analyses of fractions of a black sand from bauxite 

[Separations by Marie L. Lindberg; analyses by Janet D. Fletcher] 

Material 

Original black sand-----------------------

Minus 270-mesh----------------------------

Float in methylene iodide-------- -------- Sink in methylene iodide: 

Magnetic to hand magnetate-------------- 0.1 amp.----------------------------- .2 amp.-----------------------------

.3 amp.-----------------------------

.5 amp.----------------------------- Nonmagnetic at 0.5 amp.-----------------

lNot determined. 

Production of bauxite from Arkansas in 1949 

was 1,094,924 long tons of dried bauxite equivalent 

(Mote and Kurtz, 1951). Assuming that the average 

Table 7---Analyses of fractions of black sand 

from Wilfley table (Alcoa) 

[Separations by Marie L. Lindberg; analyses by K. J. Murata] 

Percent 

Material of sample 

Original black sand-------- 100 

Mainly siderite------------ 55 

About 90 percent ilmenite-- 32 

Ilmenite with much limonite 3 

Zircon with some anatase 

and rutile. 10 

Percent 

Nb 

0.06 

-57 

.16 

.08 

content of Nb is 0.05 percent, this corresponds to 

547.5 long tons or 1.2 million pounds of niobium--

SO percent of the amount imported by the United States 

in the same year. 

The data in table 3 show that niobium is concentrated in the red and brown muds and in the black 

sands. The data of table 4 to 7 show the niobium to 

be concentrated in the titanium-rich fraction of the 

black sands; it is probable that this is also true of the 

red and brown muds. These might, however, contain 

more rutile and sphene and less ilmenite than the 

black sands, but quantitative data are lacking. The 

problem of obtaining niobium from Arkansas bauxite 

thus appears to be one of treating a concentrate containing approximately 40 to 50 percent Ti02 and 0. 5 

to 0. 9 percent Nb. 

Most of the ilmenite processed in the 

United States is used in the manufacture of 

Ti02 pigment. This involves solution of the ore 

in acid, followed by hydrolysis t9 precipitate 

titanium dioxide. It is probable that niobium 

accompanies the titanium in this precipitation 

and that its recovery would be very difficult. 

On the other hand, the production of titanium 

metal is increasing very rapidly. This process 

involves the chlorination of titanium-rich ore to 

form TiC14. Since TiC14 boils at 136°C and 

NbC15 at 243°C, conditions are favorable for 

obtaining good separations, as recently demonstrated 

Percent of Percent of 

total -80, +270 Percent Nb 

100 --- 0.064 

24.7 --- (l) 

10.9 14.5 (l) 

38.8 51.5 .025 

6.7 8.9 .035 

4.4 5.8 .064 

12.0 15.9 .14 

2.1 2.8 .66 

.4 -5 .45 

100.0 99-9 

on a laboratory scale by Atkinson, Steigman, 

and Hiskey (1952). Further research on the 

process is obviously needed, as well as a study 

of the economic factors. 

Research is also needed on the possibility of 

using rutile, brookite, or perovskite, such as that 

obtained from alkalic rocks. As readily seen from 

the data in table 8, these minerals contain much 

higher Nb contents than the ilmenite concentrates 

from Arkansas bauxite, but they lack the advantage 

of known availability in large tonnages. The possibility of recovering niobium from perovskite-pyrochlore in Q.lkalic rocks has been discussed for the 

deposits of the Kola Feninsula, U. S. S. R. (Eliseev 

and Nefedov (1940), Gerasimovsky (1939, 1940); for 

the deposits of the Kaiserstuhl, Baden, Germany 

(Leibrandt, 1948); and for the deposits of Tororol, 

Uganda (Hudson and Dunkin, 1951). 

The Geological Survey is continuing its investigations of rutile, brookite, anq perovskite at Magnet 

Cove, Ark. , and of similar deposits elsewhere. It is 

to be hoped that metallurgical researches on the 

recovery of niobium from these titanium minerals 

will be carried out by other laboratories. 

LITERATURE CITED 

Ahrens, L. H., 1952, The use of ionization potentials, 

I, Ionic radii of the elements: Geochim. et 

Cosmochim. Acta, vol. 2, pp. 155-169. 

Atkinson, R. H., Steigman, Joseph, and Hiskey,C. F., 

1952, Analytical chemistry of niobium and tantalum: 

Anal. <;::hemistry, vol. 24, pp. 477-488. 

Borovskiy, I. B. , and Blokhin, M. A., 1937, The 

analysis of materials by the X-ray spectroscopical 

method: A cad. sci. U. R. s. S. Bull., Ser. geol., 

no. 5, pp. 929-936. 

Bykova, V. S., 1941, Chemical composition of the 

Lovazero loparite and a method for its analysis: 

Acad. sci. U. R. S. S. Comptes rendus, vol. 33, 

pp. 136-130. 

Calhoun, W. A., 1950, Titanium and iron minerals 

from black sands in bauxite: U. S. Bur. Mines 

Rept. Investigations 4621, 16 pp. 

Chernik, G. F., 1914, Chemical studies of minerals 

from Ceylon placers: Acad. Sci. St. Petersburg 

Bull., 1914, pp. 41-51; Neues Jahrb. Mineral., 

Referate 1, 1915, pp. 36-40. 
Chernik, G. P., 1921, Chemical analysis of an 

ilmenorutile from the Urals: Acad. sci. U. R. S. S. 

Bull., vol. 15, pp. 425-428; Mineralog. Abstracts, 

val. 2, pp. 405-406 (1925). 

Clark,J. W., 1951, Minor metals: U. S. Bur. Mines, 

Minerals Year Book for 1949, pp. 1306-1308. 

Crook, T. and Johnstone, S. J., 1912, Strueverite 

from the Federated Malay States: Mineralog. Mag., 

vol. 16, pp. 224-231. 

Dieke, G. H., and Crosswhite, H. M., 1943, Use of 

iron lines as intensity standards: Opt. Soc. 

America Jour., vol. 33, pp. 425-434. 

Edwards, A. B., 1940, .A note on some tantalumniobium minerals from western Australia: 

Australasian Inst. Min. Metallurgy Froc., no. 120, 

pp. 731-744. 

Eliseyev, Na A., and Nefedov, N. K., 1940, The 

loparite deposits of lujavrite: Proizvod. Sily 

Kol'skog Poluostrove 1940, no. 1, pp. 77-118; Chern. 

Abstracts, val. 37, p. 1679 (1943). 

Fleischer I Michael and Harder I J. 0. I 1945, The 

geochemistry of columbium and tantalum: G. S. Geol. 

Survey Report to the Manhattan District, Feb. 1945, 

revised June 1946, and reproduced as MDDC-645, 

27 pp. 

Gerasimovskiy, V. I. , 1939, Fegmatites of the 

Lovazero alkaline massif: Akad. Nauk SSSR, Inst. 

Nauk Trudy, no. 18, Mineral.- Geokhim. Ser. 5, 

pp. 1-45. 

-':""'"'"-:---:---':""'"'"-:-:---::-=--:~· 1940, Columbium and 

tantalum in the U.S.S.R. Akad. Nauk SSSR, Inst. 

Geol. Nauk. Trudy, no. 39, Mineral. -Geokhim. 

Ser. 8, pp. 49-57. 

Goldschmidt, V. M., 1937, The principles of 

distribution of chemical elements in minerals and 

rocks: Chern. Soc. London Jour., pp. 655-673. 

Gordon, Mackenzie, Jr., and Murata, K. J., 1952, 

Minor elements in Arkansas bauxite: Econ. Geology, 

vol. 47, pp. 169-179. 

Hauser, Otto, 1908, Ueber den sogennanten Dysanalyt 

von Vogtsburg im Kaiserstuhl. Zeitschr. anorg. 

Chern., vol. 60, pp.237-241 (1908). 

Hevesy, G. von, Alexander, E., and Wurstlin, K., 

1929, The abundance ratio Nb/Ta in titanium 

minerals: Zeitschr. anorg. allgem. Chern., vol. 

181, pp. 95-100. 

Hess, F. L., and Wells, R. C., 1911, An occurrence 

of strueverite: Am. Jour. Sci., 5th ser., vol. 

31, pp.432-442. 

Hudson, S. B., and Dunkin, H. H., 1951, Electrostatic 

concentration of pyrochlore from Tororo, Uganda: 

Ore Dressing Investigations, Commonwealth Sci. 

and Ind. Research Org. and Mining Dept., Univ. 

Melbourne, Investig. no.400, pp. 1-11. 

Knop, A., 1877, Dysanalyt, ein pyrochlorartiges 

Mineral. Zeitschr. Krist., vol. 1, pp. 284-296. 

10 

Kunitz, Wilhelm, 1936, The role of titanium and 

zirconium in rock-forming s1licates: Neues Jahrb. 

Mineral., Geol., Beilage-Band 70, Abt. A, H 3, 

pp, 385-466. 

Leibrandt, F, 1948, The occurrence of niobium 

minerals in the Kaiserstuhl. Mitteilungsblatt 

Badischen geol. Landesanstalt 1948, pp. 39-42. 

Mar, F. W., 1890, So-called perofskite from Magnet 

Cove, Arkansas. Am. Jour. Sci., vol. 40, 

pp. 403-405. 

Meigen, W., and Hugel, E., 1913, Ueber die chemische 

Zusammensetzung des Dysanalyts von VogtsbJ?.rg 

im Kaiserstuhl. Zeitschr. anorg. Chemie, vol. 82, 

pp. 242-248. 

Morozewicz, J, 1930, Mariupolite and related rocks: 

Mineralog. petrog. Mitt., val. 40, pp. 335-436. 

Mote, R. H., and Kurtz, H. F. (1951). U. S. Bur. 

Mines, Minerals Yearbook for 1949, p. 171. 

Myers, A. T. (1951). Improved cutting tool for 

spectroscopic electrodes. Anal. Chern. , val. 23, 

pp. 209-210. 

Panteleyev, P. G. (1938). Titanium,niobwm,and 

tantalum in the alkaline complex of the 

Il'menskiye Gory, in the Urals: A cad. sci. 

U. R. S. S. Bull., Ser. Geol., no. 5-6, pp. 827-836. 

Prior, G. T., and Zambonini, F., 1908, On 

strueverite and its relation to ilmenorutile. 

Mineralog. Mag. , val. 15, pp. 78-89. 

Rankama, Kalervo, 1948, On the geochemistry of 

niobium. Annales Acad. Sci. Fennicae, Ser. A, 

III, No. 13, pp. 1-57. 

Sahama, T. G., (1946). On the chemistry of the 

mineral titanite. Comm. geol. Finlande Bull. 

138, pp. 88-120. 

Smith, Bracewell. (1946). The geology and mineral 

resources of British Guiana. Handbook of natural 

resources of British Guiana, sec. 4, pp. 18-40; 

Mineralog. Abstracts, vol. 10, p. 292 (1948). 

Tavora, Elysiario and Scorza, E. P., 1948, 

Ocorrencia de rutilo columbiana no Brasil Ministerio 

Agric., Brazil, Div. geol. e mineral., Notas 

prelim. e estudos, no. 45, 1-60. from Colatina, 

Espirito Santo. 

Ussing, N. V., 1912, Geology of the country around 

Julianehaab, Greenland Medd. om Gr¢nla'1d val. 

38, pp. 1-426. 

Yurk, Yu. Yu., and Breser, V. M., 1940, Geochemistry of rare elements in the granitic pegmatites 

of the western Azov seacoast region: J. Geol., A cad. 

Sci. Ukrain. S. S. R., vol. 6, no. 4, pp. 131-163; 

Chern. Abstracts, vol. 35, p. 416 (1941). 

Yurk, Yu. Yu.,andTsarovskiy, I. D. (1940). Black 

ore minerals of the Mariupol' alkaline· massif. J 

Geol. (Acad. Sci. Ukrain. S. S. R. Inst. Geol.) 

vol. 7, no. 1-2, pp. 151-162; Chern. Abs., 

vol. 35, p. 3198 (1941). 
1-" 

..... 

No. 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

2i 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

33 

34 

35 

36 

37 

38 

39 

0.004 

. 01 

.013 

.015 

. 02 

.04 

. 04 

.043 

. 05 

.068 

.07 

. 084 

.13 

. 15 

.18 

.18 

• 19 

. 20 

.20 

.21 

.23 

. 26 

• 28 

1.3 

2.0 

4.3 

4.8 

6.0 

12.5 

15.2 

16.3 

19.5 

20.9 

22.5 

23.3 

0.01 

• 023 

.38 

2.4 

Table 8.--Niobium content of titanium minerals 

Locality Type of occurrence Analyst 

Rutile (including the variety ilmenorutile) (Ti02) 

Italy, Trentino, Pfitschthal--------------

Norway, S~ndeled-------------------------­

Arkansas, Magnet Cove---------------------

Finland, Tipasjarri-----------------------

Norway, Krager~--------------------------­

Virginia, Roseland------------------------

U. S. S. R., Sugamak----------------------

Norway, Bamle-----------------------------

Vermont, Hartford-------------------------

Australia, Blumberg-----------------------

Norway, Bamle-----------------------------

U. S. S. R., Kasoi Brod-------------------

Finland, Liperinsalo----------------------

Switzerland, Kriegalp -------------------- Norway, Ris~r-----------------------------

Florida-----------------------------------

Norway, Krager~--------------------------­

Italy, Pfitschthal------------------------

Florida-----------------------------------

Australia---------------------------------

Brazil------------------------------------

Florida-----------------------------------

Idaho, Clearwater-------------------------

Arkansas, Magnet Cove---------------------

Texas, Marfa-----------------~-----------­

South Dakota, Keystone--------------------

Malaya, Kuala Kangsur dist.---------------

W. Australia, Globe Hill------------------

U. S. S. R., Ilmen Mountains--------------

-------do----------------------------------

Italy, Craveggia--------------------------

Brazil, Espirito Santo, Colatina----------

British Guiana----------------------------

Norway, Ireland---------------------------

W. Australia, Melville--------------------

Nepheline syenite-----------------------

Gabbro----------------------------------

Anorthosite-----------------------------

Gabbro----------------------------------

Gabbro----------------------------------

Gabbro----------------------------------

Beach sand------------------------------

Gabbro----------------------------------· 

Beach sand------------------------------

-------do--------------------------------

Alluvial-----------------~-------------­

Beach sand------------------------------

Placer----------------------------------

Carbonate veins in nepheline syenite----

Tertiary silicified tuffs---------------

Granite pegmatite-----------------------

Placer----------------------------------

Granite pegmatite-----------------------

Alkalic rock----------------------------

------do---------------------------------

Granite pegmatite-----------------------

Placer----------------------------------

Granite pegmatite-----------------------

------do---------------------------------

Rankama ( 1948) . Hevesy and others (1929) • Do. 

Rankama ( 1948) . Hevesy and others (1929) . H. J. Rose, Jr. 

Rankama ( 1948) . Do. 

Hevesy and others (1929) . Rankama ( 1948) . Do . Do. 

Do. 

Hevesy and others (1929) . Rankama ( 1948) . J. D. Fletcher. 

Rankama ( 1948) . Hevesy and others (1929) . J. D. Fletcher . Do. 

Do . Do . Do. 

Do. 

Do. 

Hess and Wells (1911). 

Crook and Johnstone (1912). 

Edwards ( 1940) . Chernik ( 1921) . Prior and Zambonini (1908). 

Do. ~avora and Scorza (1948). 

Smith ( 1946). 

Prior and Zambonini (1908). 

Edwards ( 1940) . 

Brookite (Ti02) 

Switzerland, Riederstobel-----------------

U. S. S. R., Urals------------------------

Arkansas, Magnet Cove-------------------~-

-------do----------------------------------

Alpine cleft---------------------------- Hevesy and others (1929). 

Placer---------------------------------- Rankama (1948) . Nepheline syenite----------------------- Do. 

Altered novaculite---------------------- K.J.Murata andE.L. Hufschmidt. 
1-' 

M 

No. 

40 

41 

42 

0.032 

.047 

1.8 

43 o.oo6 

44 <.01 

45 .47 

46 3-l 

47 3-3 

48 3.4 

49 5.1 

so 5.6 

51 5.6-6.8 

52 111.3 53 15.6 

54 18.2 

55 

56 

57 

58 

59 

60 

61 

62 

63 

64 

65 

66 

67 

68 

69 

70 

71 

72 

73 

0.0002 

.006 

<.01 

<.01 

<~ 01 

.018 

. 039 

.18 

0.00002 

.0002 

. 0003 

.001 

.005 

<.01 

<.01 

<.01 

<.01 

<.o1 

<.o1 

Table 8.--Niobium content of titan~um minerals--Continued 

Locality Type of occurrence 

Anatase (Ti02) 

Switzerland, Binnenthal------------------- Alpine cleft---------------------------

------do----------------------------------- ------do--------------------------------

California, Cady Mountain----------------- Granite pegmatite----------------------

Perovskite (CaTi03 ) (including the niobian variety 

dysanalyte ana the cerian variety loparite 

U. S. S. R., Urals, Achmatovsk------------

------do-----------------------------------

U. S. S. R., Kola Peninsula---------------

Arkansas, Magnet Cove---------------------

------do-----------------------------------

Germany, Kaiserstuhl----------------------

Arkansas, Magnet Cove---------------------

------do-----------------------------------

U. S. S. R., Kola Peninsula (5 samples)---

Germany, Kaiserstuhl~--------------------­

Ceylon, Prov. Uva-------------------------

Germany, Kaiserstuhl----------------------

Nepheline syenite----------------------

------do--------------------------------

------do--------------------------------

Carbonatite----------------------------

------do--------------------------------

------do--------------------------------

Nepheline syenite----------------------

Carbonatite----------------------------

Limestone in placer--------------------

Carbonatite----------------------------

Ilmenite-mag~etite ores 

Finland, Attu Parainen--------------------

Finland, Otanmaki-------------------------

New York, Lake Sanford (9 samples)--------

Quebec, Allark Lake (2 samples) ---------- Costa Rica--------------------------------

Norway, HitterB---------------------------

U. S. S. R., Ilmen Mountains--------------

U. S. S. R., Vuorikyl£--------------------

Norway, Egersund--------------------------

South Africa-----------------~-----------­

u. S. S. R., Urals, Miask-----------------

India-------------------------------------

Norway, Blaafjeld-------------------------

New York, Adirondacks (4 samples) -------- Quebec, Baie St. Paul (5 samples) --------

North Carolina, Lenoir--------------------

Virginia, Piney River---------------------

Virginia, Roseland------------------------

Norway (3 samples)------------------------

Amphibolite----------------------------

Anorthosite-gabbro---------------------

------do--------------------------------

Granite pegmatite----------------------

Alkalic rocks--------------------------

Ilmenite (FeTiO;) 

Anorthosite----------------------------

Gabbro?--------------------------------

Granite pegmatite?---------------------

Placer---------------------------------

Anorthosite----------------------------

Anorthosite -gabbro----------------------

------do--------------------------------

Metamorphosed basic rocks--------------

Anorthosite----------------------------

Anorthosite?---------------------------

Analyst 

Rankama ( 1948) . Do. 

K. J. Murata. 

Rankama ( 1948) . Hevesy and others (1929). 

Rankama ( 1948) . · 

Mar (1890). 

Rankama ( 1948) . Houser ( 1908) . H. J. Ro1?e, Jr. 

K. J. Murata. 

Bykova ( 1941) . Meig~n and Hugel (1913). 

Chernik ( 1914) . Meigen and Hugel (1913). 

Rankama ( 1948) . Do. 

E. L. Hufschmidt. 

Do. 

Do. 

Rankama ( 1948) . Do . Do. 

Hevesy and others (1929). 

Do. 

Do . Do. 

Rankama ( 1948) . J. D. Fletcher. 

Do. 

Do. 

Do 

Do 

Do. 
........ 

c..u 

(I) 

~ 

~ 

? 

Q 

74 

75 

76 

77 

78 

79 

Bo 

81 

82 

83 

84 

85 

86 

87 

88 

89 

90 

91 

92 

93 

94 

95 

96 

97 

98 

99 

100 

101 

102 

103 

104 

105 

106 

107 

108 

109 

110 

111 

112 

113 

114 

115 

116 

117 

118 

119 

120 

.01 

.039 

.040 

.05 

.065 

-07 

.085 

.09 

.090 

. 095 

.10 

.12 

.14 

.18 

.20 

.28 

-35 

. 4 

·5 . 4-.9 

-57-.86 

0.0001 

.001 

.001 

.002 

. 002 

.011 

.02 

.02 

.023 

.03 

.03 

.09 

.10 

.13 

.15 

.20 

.20 

.21 

. 24 

.25 

• 48 

·77 

.84 

1.06 

1.12 

2.3 

Norway------------------------------------

Florida-----------------------------------

------do-----------------------------------

Australia---------------------------------

Florida-----------------------------------

------do-----------------------------------

------do-----------------------------------

Florida-----------------------------------

India, Quilon-----------------------------

------do-----------------------------------

Florida-----------------------------------

------dO-----------------------------------

India, Quilon-----------------------------

U. S. S. R., Azov region·------------------

Florida-----------------------------------

Calirornia, Tulare Co.---··----------------

U. S. S. R., Mariupol---------------------

Uganda, Tororol---------------------------

U. S. S. R., Ilmen Mountains--------------

Arkansas bauxite (4 samples)--------------

Sphene (CaTiSi05) 

Norway, Kragerp---------------------------

Switzerland, St. Gotthard-----------------

Italy, Zillerthal-------------------------

Switzerland, Binnenthal-------------------

Norway, Arendal---------------------------

Norway, Kragerp---------------------------

Norway, Spndeled--------------------------

U. S. S. R., Urals, Miask-----------------

Norway, Arendal---------------------------

Switzeriand, Binnenthal-------------------

Finland, Ylojarvi-------------------------

Canada, Eganville-------------------------

Canada, Pontiac Co.-----------------------

Norway, Rispr-----------------------------

Finland, Iivaara--------------------------

Sweden, Hajstorp--------------------------

Germany, Ascharrenburg--------------------

u. S. S. R., Transbaikalia, Sviatoy Noss--

U. S. S. R., Kola Peninsula---------------

------do-----------------------------------

Finland, Parainen-------------------------

U. S. S. R., Kola Peninsula---------------

Norway, Kragerp---------------------------

U. S. S. R., Kola Peninsula---------------

D. S. S. R., Nuolainniemi, Core-----------

U. S. S. R., Nuolainniemi, Shell----------

Placer-------------------------------~-

Beach sands----------------------------

------do--------------------------------

------do--------------------------------

------do--------------------------------

------do--------------------------------

------do--------------------------------

------do--------------------------------

------do--------------------------------

------do--------------------------------

------do--------------------------------

------do--------------------------------

------do--------------------------------

-Beach sands, derived rrom granite 

pegmatite. 

Beach sand-----------------------------

Granite pegmatite----------------------

Nepheline syenite----------------------

------do--------------------------------

------do--------------------------------

Bauxite--------------------------------

(including keilhauite variety) 

Granite pegmatite----------------------

-Gabbro---------------------------------

Gabbro---------------------------------

Nepheline syenite----------------------

Nepheline syenite----------------------

Nepheline syenite----------------------

------do--------------------------------

Limestone------------------------------

Nepheline syenite----------------------

Nepheline syenite----------------------

Granite pegmatite----------------------

------do--------------------------------

Hevesy and others (1929). 

J. D. Fletcher. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do . 

Do. 

Do. 

Do. 

Yurk and Bresser (1940). 

J. D.. Fletcher. 

Do. 

Borowsky and Blochin (1937). 

Yurk and Bresser (1940) . H. J. Rose, Jr. 

Panteleev (1938) . J. D. Fletcher. 

Hevesy and others (1929) . Do. 

Do. 

Do • 

Do. 

Do. 

Do. 

Sahama ( 1946) . Hevesy and others (1929). 

Ranka!fia ( 1948) . Sahama ( 1946) . Hevesy and others (1929). 

Rankama ( 1948) . Do. 

Do. 

Do. 

Do. 

Do • 

Sahama ( 1946) . Rankama ( 1948) . Sahama ( 1946) . Do. 

Rankama ( 1948) . Sahama (1946). 

Do.; 

Do. 
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