DEPARTMENT OF THE INTERIOR

BULLETIN

UNITED STATES

GEOLOGICAL SURVEY

No. 9O

WASHINGTON

GO VKRNMENT TAINTING OFFICE 

1892

UNITED STATES GEOLOGICAL SUKVEY

J. W. rOWELL, DIKECTOR

REPORT OF WORK DONE

IN THK

DIVISION OF CHEMISTRY AND PHYSICS

MAINLY DURING THK

FISOA.L YEA.H 189O5 91

FKANK WIGGLES WOliTH CLAEKE, CHIEF CHEMIST

WASHINGTON

GOVERNMENT PRINTING OFFICE 

1892

CCfNTENTS.

Page.

Letter of transmittal................. ...................................... 9

On the constitution of certain micas, vermiculites, and chlorites. By F. W.

Clarke and E. A. Schueider ......................................... 11

New analyses of nraninite. By W. F. Hillebrand ........................... 22

On the isomorphism and composition of thorium and uranous sulphates ...... 26

I. Chemical discussion. By W. F. Hillebrand .......................... 26

II. Crystallographic discussion. By W. H. Melville..................... 31

Powellite calcium molybdate: A new mineral species. By W. H. Melville.. 34

Mineralogical notes. By W. H. Melville .................................... 38

Natrolite from Magnet cove, Arkansas .................................. 38

Tourmaline from Nevada county, California............................. 39

Spessartite garnet from Llano county, Texas ............................ 39

Bismuthinite from Sinaloa, Mexico...................................... 40

New analyses of astrophyllite and tscheffkinite. By L. G. Eakins .......... 41

Two new meteorites. By L. G. Eakins...................................... 45

I. Meteoric iron from Pulaski county, Virginia ...»......... *............ 45

II. Stone from Washington county, Kansas.............................. 45

On the action of phosphorus oxychlorido on the ethers and chlorhydrines of

silicic acid. By H. N. Stokes....................................... 47

On the colloidal sulphides of gold. By E. A. Schueider...................... 56

Miscellaneous analyses...................................................... 62

Three minerals from Colorado .......................................... 62

Yellow smithsonite from Arkansas ...................................... 62

Rocks and clays from the zinc region of Missouri and Kansas............ 63

Two feldspars .......................................................... 65

Six sandstones.......................................................... 65

Seven marbles and dolomites............................................ 66

Nine rocks from Maryland .............................................. 66

Eruptive rock from Kentucky .......................................... 67

Four granites from Missouri ............................................ 68

Three rocks from Minnesota ............ ................................ 68

Eocks from Colorado ................................................... 69

Eocks from Montana.................................................... 70

Eocks from Arizona .................................................... 72

Eock from Eureka, Nevada ............................................. 72

Eocks from California ................................................... 73

Sinter from Queensland................................................. 74

Two clays from Florida ................................................. 74

Iron ores from West Virginia ........................................... 74

Coal and coke from West Virginia ...................................... 75

Two coals from Utah ................................................... 75

5

ILLUSTRATIONS,

Page. 

FIG. 1. Crystalline form of uranium sulphate ................................ 32

2. Crystalline form of uranium-thorium sulphate ........................ 32

3. Crystalline form of powellite............. ........................... 35

7

ETTER OF TRANSMITTAL.

DEPARTMENT OF THE INTERIOR,

U. S. GEOLOGICAL SURVEY, 

Washington, J). (?., January 1, 1892.

SIR: In accordance with established usage, this bulletin, like its 

predecessors, bulletins 9, 27, 42, 55, GO, 64, and 78, contains a record 

of work done in the division of chemistry and physics during a fiscal 

year. It is, however, incomplete in certain respects; for unfinished 

investigations are not described, and the larger researches are reserved 

for independent publication. The physical studies of Dr. Barus, for 

example, and the work of Dr. Chatard upon the Florida phosphates, 

will appear in separate form; and many analyses of value which have 

been made in the chemical laboratory are to be published in the geological reports with which they properly belong. The bulletin, however, in spite of omissions, gives a fair idea of the range and variety of 

work done in the chemical laboratory.

F. W. CLARICE,

Chief Chemist. 

Hon. J. W. POWELL,

Director.

WORK DONE IN THE DIVISION OF CHEMISTRY AND . 

PHYSICS IN 1S90-'91.

ON THE CONSTITUTION OF CERTAIN MICAS, VERMICULITES,

AND CHLORITES.

BY F. W. CLARKE AND E. A. SCHNEIDER.

In a previous paper upon the constitution of the silicates, 1 we sought 

to establish some new lines of attack upon the problem, especially with 

reference to the mica and chlorite groups. The present communication 

is to be regarded as a continuation of the same research, and by essentially the same methods ; although in some instances the experiments 

have been less elaborate, when elaborateness seemed to be unnecessary. 

Throughout the investigation the fundamental hypothesis that the 

minerals studied are substitution derivatives of normal salts has kept 

steadily in view5 and, as we believe, it has been amply justified.

Of the so-called vermiculites, two only, jefterisite and kerrite, were 

considered in our former paper; and these were shown to be trihydrated 

micas, in which the original alkalies had been replaced by hydrogen. 

To these examples we now add several others; of which two varieties 

afford excellent checks upon the earlier work. The two minerals in 

question are an altered biotite from the zircon mine in Henderson 

county, K 0., and the protovermiculite from Magnet cove, Arkansas, 

described some years ago by Konig. The analyses, with itemized 

water determinations, are as follows:

Ti02 ...... ..................

Zr0.2 ........................

A1A-- - - - - 

Po,o,- .-.-

FeO ........................

MnO.. ......................

Hen dors on county.

Analysis.

38-18 

1-08

14-02 

13-02 

2-22 

0-,'!8

Molecular 

ratio.

 036 

 021

-.138 

 081 

 031 

 005

Protovorni iculite.

Analysis.

34-03 

undot.

14-49 

7-71 

0-14 

0-09

Molecular 

ratio.

5-C7

 142 

 048 

 002 

 001

' Bulletin No. 78.

11
12 LABORATORY REPORT, 1890-'91. [BULL. 90.

MgO.. ....... ...............

CaO ........................

BaO ........................

K20 ........................

NajO .......................

H20, 105° ...................

H2 0, 250°-300° ..............

Hendevson county.

Analysis.

14-62 

0-17 

0-06 

5-40 

0-48 

3-20 

2-52 

4-80

100-75 

3-20

Molecular 

ratio.

 385 

 003

 057 

 008 

 178 

 140 

 207

Protovermieulito.

Analysis.

20-89 

"1-88

11-23 

4'55 

5-41

100-42 

11-34

Molecular 

ratio.

 522 

 034

 624 

 253 

 301

The analysis of protovermiculite agrees with that of Konig as well as 

could be expected, but is carried out somewhat more in detail. In its 

appearance the mineral was dark brown, broadly foliated, much decomposed, and very brittle. Before the blowpipe it exfoliates and fuses 

easily. The Henderson county mica was also brown, brittle, and decomposed, exfoliating when heated and fusing at the edges. Both 

minerals were examined optically by Mr. Waldema.r Liudgren. The 

protovermiculite he describes as " yellowish, containing in arborescent 

forms between the .plates a great deal of a deep yellow or reddish substance, probably hydroxide of iron. Angle of optical axes larger than 

usual. Slight pleochroisin ; thicker plates remain light between crossed 

nicols." Of the Henderson county mica he says a contains no titanium mineral. Contains a few grains of a colorless, strongly doublerefracting mineral of uncertain nature, possibly zircon. Plates nearly 

dark between crossed nicols. Angle of optical axes small, but distinctly observed." In the material selected for analysis the impurities 

rioted by Lindgren were, so far as possible, removed.

The composition of each mineral reduces quite easily, in accordance 

with the methods followed in our former work, to a mixture of simple 

isomorphous types. The only uncertainties appear to be in connection 

with the loosely combined water, which is driven off below 300°. In 

the Henderson county mica we have the molecules

/Si04 EEMgK

Al Si04 :ZMgH Al Si

.

= H3 Fe SiO4 = MgH Fe 0^ fe 

\Si04 =

in the ratio 8 : 1 : 3£ : 3. The loosely combined water is in the proper 

amount to monohydrate the four molecules; but its actual distribution 

is uncertain. In the subjoined table monohydration is provisionally 

assumed. In the protovermiculite we have the three molecules

Al Si04 EEH3
CLARKBAND 

SCHNEIDElt. CONSTITUTION OF MICAS, ETC. 13

each plus three molecules of water, in the ratio 14:6:9. As in the case 

of jeff'erisite and kerrite, the three molecules of loosely combined water 

are unlike, two being given off over sulphuric acid and the third retained rather more tenaciously.

Reducing the original analysis to 100 per cent, uniting all similar 

oxides to similar type, reckoning FeO as MgO, JSTa^O as K2O, TiO2 as 

SiO2, etc., we get the following comparison between observation and 

theory:

SiOa.............. ...........

A1203 ..... ........?.-.... ...

Fc^Oj. ......................

MgO........................

KS0 ........................

HV 0, osseutial ..............

Henderaon county.

Found.

39-70 

14-12 

13-11 

16-32 

6-17 

4-83 

5- 75

100-00

Calc.

39-90 

14-25 

13-15 

17-08 

0-17 

4-87 

4-58

100-00

Protovermiculito.

Found.

34-10 

14-52

7-72 

22-41

5-43 

15-82

100-00

Calc.

34-18 

14-78 

7-20 

22-79

5-40 

15-65

100-00

These results, taken in connection with our work on jcfferisite and 

kerrite, and with the mica theory upon which all our formulae are based, 

are exceedingly suggestive. Kerrite is essentially a trihydrated hydrophi ogopite. Protovermiculite is the same substance, commingled with 

a trihydrated hydroclintonite, in the ratio 1:1 very nearly. Jefferisite is a similar mixture of hydrobiotite and hydroclintonite, also 

trihydrated, and in the ratio 1:1. The Eenderson county mica is 

essentially a biotite, about half way transformed into a vermiculite, 

and is interesting as a transition product. The hydration of its several 

admixed molecules is naturally uncertain. At an early date we hope 

to imitate experimentally the process by Avhich a mica becomes transformed into its corresponding vermiculite.

But although the above-named minerals appear to be very simple in 

their structure and relationships, a like simplicity does not characterize 

all of the vermiculites. In some members of the group there seem to 

be a small admixture of chloritic molecules, and it is even probable 

that many intermediate stages between mica and chlorite may exist. 

As bearing upon this question we have a series of vermiculitic minerals 

from Chester and Delaware counties, Pennsylvania, some of which have 

already been studied by Cooke, Grooch, Leeds, and others, while some 

have escaped examination hitherto. To begin with, \ve may consider 

the hallite, from Nottingham, Chester County, and the vermiculites 

from Lenni (not Lerni), Delaware County. The hallite, received 

through the kindness of Mr. W. W. Jefferis, was dark bluish green, 

and agreed perfectly with the published descriptions. The Lenni mineral, partly from the collection of the late Isaac Lea; and partly gath-
14 LABORATORY REPORT, 1890^91. (BULL. 00.

ered in the field by one of us, is represented by several varieties, which 

in a large series of specimens are seen to shade into each other. Three 

varieties were examined: one, silver white, resembling outwardly an 

ordinary inica; a second, bronzy brown, like jefferisite; and the third, 

dark green, similar to clinochlore. All four substances were examined 

microscopically by Mr. Lindgren, who reports as follows:

A. HALLITE.

Corresponds exactly to Cooke's description. 1 Contains spear-shaped 

rhombic or more rarely hexagonal inclusions of a dark brown mineral 

distributed along lines cutting «ach other at angles of 60° and 120°. 

Asterism appiarently uniaxial, although the plates sometimes show slight 

double refraction between crossed nicols. *

B. WHITE LENNI.

Silvery luster in large fragments. Thin foils colorless, thicker yellowish and yellowish brown. Substance pure; no inclusions, except 

small crystals of feldspar (?) once observed. Thin lamellae very faintly 

double refracting, in streaks and patches. Interference figure a cross, 

not dissolved. Crossing lines on surface marked quite well.

C. BROWN LENNI.

Brownish yellow, similar to biotite. Hexagonal line system not 

very marked. Thin plates yellowish to deep yellowish brown. Substance pure, except containing in small foils and arborescent forms 

some Fe2 O3. Thicker plates do not extinguish in any position between 

crossed nicols. Angle of optical axes very small.

D. GREEN LENNI.

Thin larnellce colorless, thicker light to deep green. No inclusions. 

Thin lamellae faintly donble refracting; in thicker plates the cross is 

dissolved into distinct hyperbolas. Does not get dark in any position 

between crossed nicols. Pleochroism notable in sections oblique to the 

cleavage plane. Fibers deep green when parallel to the principal 

plane of the microscope, light green when perpendicular to it. No line 

systems noted on the surface.

Upon analysis, the four minerals gave the subjoined results, with 

the water determinations itemized as usual:

l Proc. Am. Acad. Arts, and Sciences, 1874, vol. 9, p. 35.
"CLAKKEAND ? 

SCHNEIDEK. 3 CONSTITUTION OF MICAS, ETC. 15

SiOz . .....................

TiO........................

A1A---------------------

Fe,0s . ...... ..............

P., r\

ToO. .....................

MnO- ......... ............

NiO---.. ..................

MgO--. ........ ...........

BaO-. ........ ............

H20, 105° .................

HaO, 250° 301)°............

A. Hallito.

155 -54

9-74

0-28

'0-25

o-io

30-05

2-64

1-23

10-91

99-87

B. Leuiii 1.

36-72

A.-IQ

5*37

0-20

(V19

0-31

0-20

29-40

0-40

2-08

8-69

100-39 

6-92

C. Lonui 2.

35-09

A.RQ

12-05

0-07

0-11

27-62

5-70

.1-98

9-22

99-95 

5-84

D. Lcniii 3.

34-90

o-io

ft- 17

A. 91

fl.OO

0*17

A-10

08-91

4-99

1.00

9-88

99-60 

5'21

In these analyses we at once see that the combined water is mostly 

in excess of the crystalline water, and that the formula} deduced must 

be correspondingly modified. The molecular ratios are as follows:

ttiH

R.&...... .................. '.. ......

1>A

Aq........ ..- ...................

A.

 592

 152

 7CO

 COG

 215

B.

 614

 134

 744

 483

 504

C.

 591

 G98

 512

 427

D.

 583

 159

 712

' -549

 366

In order to learn something as to the distribution of the hydroxyl 

indicated by these ratios, resort was had to the process of heating in 

dry, gaseous, hydrochloric acid, as described in our former paper. 

From this test, however, the brown Lenni vermiculite was omitted, as 

being intermediate in its character between the white and the green. 

Each experiment was made at the temperature 383°-412°.

A.

16*

3-42

8-09

 202

B.

16

1-J)8

 158

D.

17

1 P\tl

fi.K7

 164

Here it is assumed, ou the grounds of our former work, that the 

magnesia rendered soluble by gaseous HC1 is present as MgOH. 

Eepresenting this by* the symbol R/, the three verrniculites give the 

following empirical formulae:

Hallite .................. R'//3MR"558R'2o-;H101 o(SiO^O«,i, 215 aq.

White Leuiii............. R^R'VjR'ifisHgos (Si0^liMOi5y, 504 aq.

Grocu ................... B'":jl«R"M8R/ lwHy34 (SiOOcwOws, 366 aq.
16 LABORATORY REPORT, 1890-91. [BULL. 90.

These reduce at once, subject to small uncertainties as to hygroscopic 

water, to mixtures of molecules of the hydroclintonite and hydro-phlogopite types, with small amounts of chloritic compounds Mg(SiO4 ) 2 

(MgOH)6 and Mg2 (SiO4 )2H4 . Upon this basis the three minerals become :

Hallite.

White Lenni

Green Lenni.

.Al(SiO4 ) 3Mg3H3 

A10sMgSi04H3 

Mg(Si04 ) a (MgOH)6 

Mg,(Si04 )*H4

.Al(Si04 )3Mg,H3 

A10,MgSi04H3 

Mg(Si04 ),(MgOH)8

.Al(Si04 ) 3Mg3H;) 

A102MgSi04H3 

Mg(Si04 ).2 (MgOH)6

3aq.

3aq.

Molecules.

....... 7

....... 18

....... 3

....... 2

....... 6

....... 5

....... 1

....... 4

....... 8

....... 1

The actual ratios observed Avere slightly more complex, but the foregoing expressions accord well with the analyses. Here, as previously, 

we may reduce the analyses to typical form and 100 per cent, reckoning Fe2O3 as A12O3, etc. The comparison is as follows:

Analyses reduced.

sio2 . .................................

AljOs-- ...............................

MgO .................................

HaO...... .............................

Aq. ...................................

MgO in MgOH ..................:.....

A(Hallite).

36-93

16-13

31-58

11-34

4-02

100-00

8-09

B (White).

37-56

14-92

30-41

8-86

9-25

100-00

6-30

D (Green).

36-33

16-83

29-44

10-26

6-84

100-00

6-57

Calculated.

Si02 ... ......... ......................

A\i03 .. ................... ............

MS0...... ............................

H2 0 ..................................

Aq...................... .............

MgO in MgOH .......................

A.

36-47

15-82

31-75

11-27

4-69

100-00

8-93

B.

14-25

30-49

8-92

Q.OQ

100-00 

6-10

D.

36-61

16-97

10-47

6-00

100-00

6-66

When we consider the nature of the vermiculites, as products of 

alteration, the agreement here shown is fully as close as could be 

expected. Many well crystallized minerals, fresh and unaltered, are 

less simply interpreted. a

On the 19th of February, 189.1, Prof. Tschermak read before the Vienna Academy a paper on the chlorite group, 1 in which he referred

1 Sitzungsb. Wien. Akael., 1891, vol. 100, i». 31.
CONSTITUTION OF MICAS, ETC. 17

certain vermioulites to that class of minerals. lie also put forth some 

views concerning the constitution of the chlorites, which, however, we 

can not discuss in the present communication.

One fundamental molecule, regarded by Tschermak as a constituent 

of most chlorites, we may adopt for present purposes, under slightly 

different structural form from his. This is the " amesite substance," 

SiAl2Mg2H4O9, written by Tschermak SiAl2H2O7 (MgOH)2 . In default 

of experimental evidence this may be transformed into OMg2 SiO4 

(A1H2O2 )2 , when it becomes part of a natural chloritic series parallel 

with the micas, thus:

Normal orthosilicate........ Al4 (Si04 )s Mg4 (SiQ4 )2

Whence we derive Micas. Chloritos.

Al^SiO^jR';, Mg3 (Si04 )2R'2

Al3 (SiO4 )3R'(i Mg2 (SiO4 ) 2R'<

Al (Si04 )3R'9 Mg (Si04 ) 2R/G /°v Mg A1-0/K Q / \Si0 _R, \Si04EER'3 °\Mg/ Sl°4 -R '

In other words, the "amesite substance" in our chlorite series is the 

basic equivalent of the clintonite molecule among the micas, and is 

applicable to the solution of certain obscure problems. Some of the 

vermiculites, as Tschermak suggests, are probably chlorites, and two 

examples have come under our notice in which this view is partly sustained. Both were originally received from Mr. Jeft'eris; one from the 

corundum mine at JSTewlin, Chester county, Pa., and the other from Middletown, Delaware county, in the same state. The Newlin mineral 

was dull green, and much resembled culsageeite both outwardly and 

optically. The Middletown vermicuhte was bright golden yellow; 

strongly exfoliating before the blowpipe and fusible on the edges. It 

was found upon the farm of Mr. James Painter, whence Mr. Jefferis 

named it provisionally "painterite," a name which seems also to have 

been applied to a peculiar brownish, waxy, feldspathic matrix in which 

the broad golden laminse were imbedded. A second sample of it was 

later collected by one of us. According to an optical examination by 

Mr. Liudgren, the matrix of the "painterite" is a mixture of plagioclase 

feldspar, probably labradorite, with serpentine. Concerning the three 

vermiculites he makes the following notes:

A. FROM NEWL1N.

Hexagonal surface marking quite distinct. Bluish green. In thin 

lamellae colorless to pale bluish green. Substance pure. The greenish color is distributed somewhat unevenly through the.miueral. Axial 

angle unusually large, being at least 25°.

B. "PAINTERITE" RECEIVED FROM JEFFERIS.

Yellowish brown. Strong hexagonal marking on the surface. Thin 

lamellae colored yellowish by numerous interpositions of a very finely 

Bull. 90 2
18 LABOEATORY REPORT, 1890-'91. [BULL. 90.

distributed substan ce, probably hydroxide of iron. Even thin foils show 

slight double refraction between crossed nicols, and do not extinguish 

in any position. Angle of optical axes small but distinct.

c. "PAINTERITE" COLLECTED BY SCHNEIDER.

Surface marking quite distinct. Contains a great number of small 

foils of Fe2O3, and also some yellowish, finely divided substance. Not 

enough materially to affect the analysis. Otherwise like B. Analysis 

as follows: A, Newlin; B, painterite from Jefferis; C, painterite collected by Schneider; D, matrix of painterite.

*

SiO........ .........................

TiO....... ..........................

A1A ...............................

Cr,0». ............ ..................

Fe,0g ....... ........................

FeO ................................

MnO-- ..............................

NiO. ...............................

MgO.. ..............................

CaO ................................

KjO...-. ...........................

Na,/). ...... ........................

H20, 105°.. .........................

HjO, 250°-300° ......................

A.

31-23

17-52

0-14

4-70

i -on

0-20

0-33

31-30

1-08

0-40

12'15

100-31

B.

34-86

11-64

3-78

0-20

0'14

31-32

0-07

1-64

1 -A'*

1 ^-7^

100-43

C.

33-95

1O. KO

4-40

0-20

0-23

30-56

1 .F.ft

0-59

16-46

100-47

D.

52-47

91 -79

1-23

0-17

9-26

<l'9n

0.63

5-09

1-14

99-70

Upon treating the three veriniculites with gaseous hydrochloric acid 

at 383°-412°, the following results Avere obtained:

A.

8

1-flQ

5-86

 146

B.

191

 AH

8-26

 907

c.

19

 7fi

9-56

 O*>Q

The molecular ratios are:

SKV-... ............................

 p f\

EO ...................................

H20 ..................................

An

A.

 520

 202

 808

 fi7<i

 080

B.

 581

 138

 789

 875

 148

C.

 566

 T»ft

 770

 914

 119
CLARKE AND ) 

8CHNBIDEK. 3 CONSTITUTION OF MICAS, ETC. 19

In these examples the Avater (Aq.) expelled below 300° is so small in 

amount that it may be left out of consideration. Part of it undoubtedly 

represents hydrated molecules, which, however, are relatively so few 

in number that they may be for present purposes disregarded.

From the remaining ratios, writing MgOH as R', the subjoined empirical formula) are directly derived:

Newliu ......................... R" '4(M E"^ R'U8 H)204 (SiO<)52o Om.

"Painterite" B.................R'"«8 R"B« R'so? H, (SiO<)68 i O709.

"Paiuterite" C................ .R'"3oo R"«,i R'm HI589 (Si04 )aa Ow,.

Reduced to structural form, these give less satisfactory results than 

the previously considered vermiculites. The Newlin mineral may be 

regarded as nearly a hydroclintonite, AlO2MgSiOtH3, with an admixture of an amesite-like compound, Mg2OSiO4 (MgOH)2 , in the ratio 4:1. 

In reality the mixture is more complicated and must contain other 

molecules. The "painterite" C is wholly chloritic, containing the ainesite molecule Mg2OSiO4 ( A1H2O2 ) 2, with the molecules Mg(SiO4 ) 2 (MgOH)6 

and Mg(Si04 )2H6, in the ratio 8:2:9. These compare with the actual 

analyses, reduced to typical form and 100 per cent, thus:

GiO

AJ,0....... .................

MgO. .......................

H2 0 ........................

MgO in MgOH .............

Newlin.

Found.

32-42 

21-39 

33-57 

12-62

100-00

6-09

Calc.

31-57 

21-47 

33-69 

13-27

100-00 

8-42

"Pain tori to."

Pound.

35-03 

16-22 

31-77 

16-98

100-00 

8-56

Calc.

35-59 

16-13 

30-84 

17-44

100-00 

9-49

The "painterite" B reduces less easily, but satisfies all the required 

conditions. It is like 0, but contains other chloritic molecules in somewhat complex ratios. It must be remembered that all these minerals 

are mixtures, and the fact that they are reducible at all to simple expressions is a strong point in favor of the theory adopted for the chlorites and micas in general.

A very interesting example of the way in which the chloritic vermiculites approach the serpentines in composition and character has been 

furnished us by Mr. G. P. Merrill, of the U. S. National Museum. It 

was found by him at Old Wolf quarry, Chestnut hill, Easton, Pa., and 

is described by him as follows:

It occurs in the form of bright yellowish green inelastic scales of all sizes up to 

an inch in diameter, associated with a compact tremolite rock, which is here quarried and pulverized for use as a filler in paper manufacture. The character of the 

rock is greatly varied, but at the quarry opening the prevailing material is tremolite, more or less altered into serpentine, the vermiculite and other secondary products including calcite in both fibrous and granular forms.
20 LABORATORY REPORT, 1890-'91. [BULL. 90.

The vermiculite, although occurring iu plates of considerable thickness, readily 

separable into thin folise, never, so far as observed, shows good crystal outlines. 

Optically it is biaxial and negative, though the axial angle is small, basal plates in 

the thin section-showing a black cross, which scarcely opens at all during the revolution of the stage. Cleavage plates a millimeter or more in thickness show plainly 

the biaxial character, though the figure is somewhat distorted. Dispersion, p<^v.

The surface of the plates is at times plainly marked by sharp lines crossing at 

angles of 60° and 120°, and along which the mineral frequently separates readily. 

Before the blowpipe the mineral exfoliates and fuses readily on the edges to a thin 

glass.

According to Mr. Merrill this mineral is sometimes seen in cabinets 

labeled "talc;" and, indeed, in its appearance it resembles both talc 

and serpentine. Upon analysis the following results were obtained, 

the percentage of K2O representing two identical determinations:

SiOs ........................

Al^03 . ......................

FeA...... .................

MgO...... ..................

K.,0 ........................

Na,0 .......................

H20, 105° ...................

H20,250° 300°..............

Analysis.

43-71

3-59

0-90

38-58

2-22

0-13

0-46

0'09

10-70

100-38

Molecular ratios.

 79ft

 035

 006

 964

 023

 002

 594

Treated with dry, gaseous HC1 at 3S3°-412o for 16£ hours, 4-3G per 

cent of magnesia became soluble, corresponding in molecular ratio to 

109 mol. MgOH. Hence the mineral, although resembling serpentine 

in general composition, differs from the latter in its proportion of this 

molecular group.

Upon treatment with aqueous HOI, of specific gravity 1-12, a small 

portion remained undecomposed. Ten grammes of the mineral were 

therefore digested with the acid for three days on the water bath, and the 

residue was afterwards boiled out with a solution of sodium carbonate 

to remove liberated silica. The remaining residue, amounting to 3-10 

per cent of the original material, was then analyzed separately and 

found to contain 

MgO.

............................................... 64-53

............................................... 2'03

............................................... 33-04

99-60

All the potash went into solution; whence it seems probable that no 

muscovite was present. The ratios of the insoluble residue agree very 

closely with those of talc, and we may therefore assume that mineral 

to be present as an impurity. Deducting from the molecular ratios
SCHNEIDE } CONSTITUTION OF MICAS, ETC, 21

given above the quantity of talc indicated by experiment, we get for 

the empirical formula of the mineral the expression 

which becomes, if the excess of oxygen is regarded as hydroxyl, with 

(MgOH)io9 as observed,

Mg829K50H889(MgOH) 109 (AlH202) 82 (OH)9.

The small excess of hydroxyl is probably due to undistributed errors 

of analysis, and may be added to the MgOH, bringing the latter to 118 

and reducing the Mg to 820. Then, generalizing, by uniting all the 

univalent groups arid atoms, we get as an ultimate formula 

Mg82() (SiO4 )G95"R'ii:,9 , 

which equals, almost exactly,

125 Mg3 (SiO4 )2E/2 + 223 Mg2 (SiO4 )2K'4 ,

a result in accordance with our serpentine-chlorite theory. The distribution of the several components of B/ is, however, not clear and 

remains to be ascertained. IsTo other discussion of the analysis appears 

to give as satisfactory results as this, and we have tried several methods of reduction, representing various hypotheses.

One other mineral examined during this investigation remains to be 

noticed, a pale yellowish green mica collected by Mr. G. P. Merrill at 

a granite quarry in Auburn, Me., near where the Maine Central railroad crosses the Androscoggin river. It occurs in direct contact with 

ordinary, broadly foliated muscovite, sometimes forming marginal 

growths about the plates of the latter mineral, like lepidolite. Analysis gave :

Si02 ........................................................ 46-54

A1203 ....................................................... 34-96

J?6aOt..... .................................................. 1-59

MgO.... .................................................... 0-32

K2 0 ........................................................ 10-38

..... ................................................. 0-41

F ........................................................... none.

................................................. 0-71

H3O, ignition ............................................... 4'72

99-63

This is the composition of muscovite, which the mica undoubtedly is. 

The case is interesting, however, as showing a secondary growth of 

muscovite on muscovite, with a marked diiference in outward appearance between, the two formations.
NEW ANALYSES OF URANINITE.

BY W. F. HlLLEBRAND.

Since the publication of a former paper on the occurrence of nitrogen 

in uraninite and on the composition of uraninite in general1 DO advance 

has been made toward clearing up the mystery surrounding the composition of that mineral, although considerable work has been done in 

certain directions, some of which is of sufficient interest to be produced 

later in a separate publication. In addition, several analyses of uraninite have been made, the material being in part from localities hitherto 

unrepresented by analytical data, and these form the subject of the 

present paper.

A first glance sufficed to show that the specimens were not fresh and 

that therefore analysis could throw no light on the ultimate composition of the mineral, but valuable data to be obtained as to the presence 

or absence of nitrogen and of the rare earths furnished ample excuse 

for the work.

No. la is a reanalysis of nivenite from Llano county, Tex., the material for which was kindly given by Mr. W. E. Hidden. It agrees in 

the main with the original analysis of this variety by Hidden and Mackintosh,3 which is reproduced under 16, and it confirms the presence of 

nitrogen, suspected but not proved by them. A small remnant of their 

original powdered sample gave me 0-52 per cent of nitrogen. In a the 

earths appear in slightly greater total amount than in ft and they are 

more subdivided into groups and elements, which accounts fully for the 

difference between the atomic weights of the metals of the yttrium group 

of the two analyses. It was rendered certain by a second test that a 

group of earths whose sulphates are insoluble in potassium sulphate, 

other than those of Th, Zr, and Ce, is present.3 A very satisfactory 

turmeric-paper reaction for zirconia was obtained in this analysis, as

1 Am. Jour. Sci., 3d ser., vol. 40, p. 384; Bull. TJ. S. Geol. Survey, No. 78, 1889-'90, p. 43.

1 Am. Jour. Sci., 3d ser., 1889, vol. 38, p. 481.

3 It may be here remarked that the subdivision of the earths into the groups indicated by (La, Di) zOj 

and (T, ErJjOs in all my former analyses should not be taken too literally. By the former are meant 

those earths insoluble in potassium sulphate and by the latter those soluble iii that reagent.

22
HILLEBRAND.] NEW ANALYSES OF URANINITE. 23

also in that next following, which Avould go to show that the hypothetical ZrO2 of several of my earlier analyses was probably in fact 

zirconia. The cause of the considerable loss shown by the analysis is 

not known. It may be mentioned that nivenite is more soluble than 

any uraninite heretofore examined by me, not even excepting cleveite. 

One hour sufficed for complete decomposition in very dilute sulphuric 

acid (1H2 SO4 to 6H2O) at the temperature of boiling water.

UOa ..............

TJ03 ..............

ThOj. ............

Zr02 .... ..........

CeOj....... .......

CaO ..............

PbO....... .......

HaO ..............

N.................

SiO, ..............

FeaOg...... .......

Al,0,».... .. ......

MgO....... .......

Na.,0 .............

Bi2 03 .............

CuO ..............

MnO....... .......

u r\

V,0...............

W f\

Mo03 ...... .......

SO,... ............

I. Llano county, 

Tex.

o. Hlllehrand.

44-17 

20-89 

C-G9 

0-34 

0-34 

2-30 

19-46 

0-32 

10-08 

1-48 

0-54 

**0.4G

tt 1-47 

0-14

98-74 

8-29

b. Hidden 

and 

Mackintosh.

46-75 

19-89 

7-57

J 11-22

10-16

H2-54

1.22 

0-58

99-93 

8-01

II. Marietta, 

S.C.

| * 83-95

1-65 

0-20 

0-19 

2-05 

§6-16 

0-41 

3-58 

undet. 

undet.

| 0-20 

trace.

trace.

98-39

m. vnleneuve 

P., Ouehec, Canada.

41-06 

34-67 

6-41

(?) 

0-40 

1-11 

|| 2-57 

0-39 

11-27 

1-47 

0-86 

t 0-19 

I 0-13 

0-10

0-09

'

100-72

IV._Johanngeorgenstadt, 

Saxony.

59-30 

22-33

none.

1-00 

6-39 

3.17 

0-02 

0-50

0-21 

0-20 

0-17 

0-31 

0-75 

0-17 

0-09 

0-06 

2-34

I 0-75 

0-19

97-95 

6-89

* As TTjOg. t Atomic weight, 111-4. J Atomic weight, 124-2. § Atomic weight, 113-6. The oxalates of this group were white, not pink like those in la, hut the color of the ignited oxides was the 

same in both cases and very light. II Atomic weight, 111-2, approximately. H Ignition. ** From 

thorogummite. tt Mainly fergusonite.

No. II is from a new locality, Marietta, Greenville county, South Carolina, and the total amount found, a few small fragments, was kindly 

given by Mr. W. E. Hidden for examination. It was impossible to free 

the least altered portions from the yellow and orange alteration products with which they were intimately commingled; therefore the analysis 

represents the composition of a mixture. Unfortunately also the portion in which UO2 and K were to be estimated was lost, but it was
24 LABOEATORY KEPOKT, 1890-'91. [BULL. 90.

seen that the mineral was very soluble and gave off considerable gas. 

From the preponderance of the yttrinui group over the other rare 

earths the mineral is to be classed with nivenite and cleveite rather 

than with those varieties rich in thoria, a conclusion already foreshadowed by its ready solubility.

No. in is an analysis of uraninite from the Villeneuve mica mine, 

township of Villeneuve, Ottawa county, province of Quebec, Canada. 

To Mr. Or. C. Hoffman, of the Canadian Geological Survey, who first 

recognized and reported this occurrence, 3 I am indebted for the material analyzed. It was evidently somewhat altered and was accompanied by oxidized alteration products. Hoffman gives the density of 

a piece as 9-055. Crystalline form was lacking, but it unquestionably 

belongs to the crystallized uraninites, being found, like most if not all 

of them, in coarse granite (pegmatite).

No. iv represents the composition of a specimen from Johanngeorgenstadt, in Saxony, received from Mr. A. Lb'sch, of St. Petersburg, 

through Mr. E. A. Schneider, of the U. S. Geological Survey. Notwithstanding the altered and crumbling character of the specimen it is 

proper to publish the analysis since the only one previously made that 

has come under my observation, by Pfaff in 1822, is very incomplete. 

By panning a very fair article as regards visible impurity was obtained. 

It is not known wherein the loss is to be sought. Like the great mass 

of the Bohemian mineral.this showed no evidence of ever having been 

crystallized, and as in that also rare earths are absent, and also nitrogen, except for an uncertain trace.

From the analyses of uraninite thus far made it appears that the 

species may be broadly divided into two groups, the one of which is 

characterized by the presence of rare earths, the other by their absence. 

With the former group nitrogen appears to be invariably associated, 

while in the latter it is present, if at all, only in minute quantity. Besides these chemical differences there is one of another kind, for probably all varieties of the first group occur in more or less well defined 

crystals, while the members of the second group are generally, if not 

altogether, massive and free from crystalline form. These differences 

suggest naturally a dissimilarity of origin and environment. Examination shows that the manner of occurrence and the association of 

other minerals are different and in such a way as to render an unlike 

immediate origin probable. All of the rare earth uraninites, with exception of the zirconiferous variety from Black Hawk, Colorado, occur 

as an apparently original constituent of coarse granites (chiefly pegrnatitic), while the others are evidently of secondary formation, as evidenced by their presence in metalliferous veins in more or less intimate 

association with numerous sulphides of silver, lead, cobalt, nickel, iron, 

zinc, copper, etc. The Colorado variety occupies an anomalous position as regards the two groups. I prefer to regard it provisionally as

1 Aimual Report Cau. Geol. Surv., 1880, vol. 2, Report T, p. 10.
HILLEBHAND.] NEW ANALYSES OP URANINITE. 25

a member of the second group, where its mode of occurrence and want 

of crystalline form as well as small percentage of nitrogen seem to 

place it, although its zirconia and traces of other earths would admit it 

to the first.

Attention is called to the above points merely to show that the 

chemical and physical differences of the two groups may be susceptible 

of more simple explanation than would appear from, the face of the 

analyses.
ON THE ISOMORPHISM AND COMPOSITION OF THORIUM AND 

URANOUS SULPHATES.

BY W. F. HlLLEBRAND AND W. H. MELVILLE.

I. CHEMICAL DISCUSSION, BY W. F. HlLLEBRAND.

During the course of an extended investigation on uraninite it was 

often necessary to decompose the mineral in sealed tubes with sulphuric 

acid.1 At first a deposit was generally observed on removing the tubes 

from the oven, the character of which depended on the concentration 

of the acid and the presence or absence of thoria in the mineral. In the 

absence of this earth it took the form of a greenish powder with a strong 

acid, and of bright green, brilliantly reflecting crystals when a weak 

acid was used, unless the ratio of liquid to mineral was sufficiently high 

in the latter case to prevent crystallization. As might naturally be 

supposed, these crystals were hydrated uranous sulphate. The best 

results as regards size of crystals were obtained with an acid containing one part of sulphuric acid to five or six of water, by volume. With 

about 100 parts by weight of such an acid to one of UO2, it might 

pretty confidently be expected that no crystallization would take place.

In presence of thoria the green crystals still appeared, but they then 

contained thorium as well as uranium, and accompanying them was a 

beautiful white coherent spongy mass extending the length of the tube 

and consisting of a network of microscopic needles grouped in radiating 

bunches. This was likewise a double sulphate of uranium and thorium, 

resembling in every respect the deposit formed under similar conditions from a solution of thorium sulphate alone, except that when 

washed, dried, and compacted together there was a faint greenish tinge 

to it. Ordinarily the two forms of double salt appeared together, and 

it even seemed as if under favorable conditions, which have not yet been 

precisely determined, the crop of green crystals might be increased at the 

expense of the white deposit. At least on one occasion, when the heating 

was prolonged for several days, the latter gradually disappeared, while 

the former increased in size and number. The white deposit always preceded the green crystals, and, by regulation of the proportions of oxide 

and of acid and of duration of heating, it is possible in practice to obtain the former alone if desired.

In order to secure material for exact chemical and crystallographical 

determinations recourse was had to artificially prepared TJ3O8 and ThOj,

'Bull. U. S. Geological Survey, No. 78, p. 43, 1889-'90. 

26
HILLEBRAND 

AND MELVILLE. THORIUM AND URANOUS SULPHATES. 27

by using which, either alone or mixed, in varying proportions, different 

products were obtained. Neither uraninite nor UO2 is well adapted 

for this purpose, because of contamination of the crystals by sulphate 

of lead in the one case and by undissolved UO2 in the other. Even 

when using U3O8 care must be taken to avoid a like result by fine pulverization and avoidance of excess of oxide compared with acid. So little 

soluble are the green crystals that over 50 per cent of the UO2 in uraninite or TJ3O8 can generally be obtained as sulphate. Hence it follows 

that when TJO2 is to be estimated volumetrically care must be taken to 

use sufficient dilute acid to render impossible the formation of these 

crystals. The white spongy deposit is not a hindrance to exact estimation of UO2 by potassium permanganate, for it dissolves readily in 

cold water, though with extreme slowness Avhen once it has been compressed.

The green crystals were separated from their mother liquor in a 

Goocli crucible, without asbestus felt, with the aid of suction; they-were 

at once washed with hot dilute sulphuric acid, then with alcohol, and 

finally with ether. They were allowed to dry thoroughly in the air 

and were analyzed in that condition. It was found by experiment that 

alcohol was practically without solvent action on the sulphates and 

that none of the water of crystallization was removed by it. If both 

forms of deposition occurred at one time the spongy one was first removed with great ease by two or three rapid washings with cold water, 

the network of fine needles being partly dissolved and partly carried 

through the holes in the crucible by the powerful suction, after which 

alcohol and ether were used as before. The results of analyses were as 

follows:

TJO,.. ......................

ThO, ....... ................

SO3 - ........................

H,0 ........................

I

Analysis.

49-18

3-59

32-08

14-18

99-03

Molecular ratio.

| 3-00

2-05

4-04

-I

Analysis.

48MO

5-58

31-27

14.84

100-09

I.

Molecular ratio.

J 1-00

1-96

4-13

A sample of uraninite decomposed by dilute sulphuric acid in a tube 

at about 170° C. furnished the product whose analysis is given under I. 

An earlier and very similar analysis of another preparation may be 

found on p. 50 of the bulletin already cited. The loss is mainly if not 

altogether undetermined PbO from included PbSO4 , which accounts 

in part for the excess of SO3 found. For No. n U 3O8 and ThO2 were 

taken in such proportion that there should be about six times as much 

TJO2 as of ThO2 . Inasmuch as only 0-1622 gramme was available for 

SO3 and H2O determinations in this analysis the ratio is not bad. One
28 LABORATOEY REPORT, 1890-791. [BULL. 90.

or two attempts to obtain a product with more ThO2 and less TJO2, by 

starting with correspondingly different proportions of ThO2 and U3O8, 

were unsuccessful, perhaps because of the tendency of the thorium sulphate to separate at once in the spongy state and thus to reduce the 

amount available for slow crystallization with the uranium. The specific 

gravity of No. II was kindly determined by Mr. L. Gr. Bakins in alcohol 

of -7956 density. It was found to be 4-563 at 24-3° 0., which reduced 

to water at the same temperature as standard becomes 3-63. The material examined contained 1-04 per cent of undissolved U3O8 which does 

not appear in the analysis, and allowing for this a density of 7-3 (Clarke's 

tables) that of the double sulphate having the given composition is 3-61 

at 24-3° 0.

The uranium sulphate, of which the analysis is here given, was obtained by decomposing U;{O8 with dilute sulphuric acid in the manner 

already mentioned. Its density was not ascertained.

in.

no,,. .............

sos . ..............

H20 ..............

Analysis.

53-99

31-94

14-13

100-06

Molecular 

ratio.

1-00

2-00

3-94

It appears, as was to be expected, that thorium is capable of replacing uranium in the sulphate of the latter, which holds in combination 

four molecules of water. That this is a true case of isomorphism is 

most fully shown by Mr. W. H. Melville in the crystallographical part 

of this paper, although the habit of the uranium sulphate differs from 

that of the double salt.

While, as above stated, failure resulted from attempts to lower the 

ratio between ThO2 and UO2 in the green double salt, it was found that 

the spongy mass, which almost always formed in the tubes when thoriferous urauinite was decomposed with dilute sulphuric acid, contained a 

very much higher proportion of ThO2 , and that by taking the dioxides 

in varying proportions double salts of correspondingly different composition could be readily obtained, as shown by the following analyses:

TrOg...... ...................

ThOg .......................

dn

H20 (diff.) ..................

1

Analysis.

34-34

19-84

31-48

14-34

100-00

Molecular ratio.

| 1-00

1-95

3-95

I

Analysis.

c 16-92

I 36-07

32-66

14-35

100-00

r.

Molecular ratio.

| 1-00

2-05

4-01
A£" M mLK.} THORIUM AND URANOUS SULPHATES. 29

Both suits Avere obtained from a mixture, of U3O,, and TliO2. In case 

of No. II the proportion was sucli that the UO2 of the U3O« Avas to the 

ThO2 as 2 to 1. It happened that the tube containing this preparation 

lay unopened for several weeks after removal from the oven, but during 

this time there had been no perceptible resolution of the precipitate, 

which on agitation made a thick emulsion with the acid. Both products were thrown on a Grooch crucible without asbestus felt, quickly 

washed twice or thrice with hot dilute sulphuric acid and then with 

alcohol and ether, whereuoon they were allowed to dry thoroughly in 

the air.

There is no reason to doubt the isomorphism of this salt \vith that 

formed under similar conditions from thorium alone, but whether these 

are crystallographically referable to the green crystals before described 

or form a new case of dimorphism must remain undetermined until the 

crystallographic features of the former are known. In polarized light 

the needles of the double salt extinguish apparently parallel to their 

length.

Such contradictory statements appear in the literature of the subject 

regarding the composition of thorium sulphate separated from hot acid 

solutions, some authorities claiming four and a half molecules of water 

of crystallization and others only four, that it is very satisfactory to have 

evidence like that furnished by the above analyses to throw light upon 

the question. The tendency of late years has been to admit a mutual 

replaceability of ThO2 and UO2 in chemical compounds, though no direct 

proof seems to have been heretofore established, 1 and it was therefore 

reasonable to suppose that the composition of the thorium sulphate in 

question should correspond with that of the well known uranous sulphate 

with four molecules of water. In the light of the above analyses there 

is no room to doubt the complete isomorphism of the two sulphates, and 

that Demarcay2 and Koozeboom3 were right in accepting the formula 

ThO4 (SO2 ) 2 , 4H2O, derivable from the more or less incomplete analyses 

of Berzelius, Berlin, and Chydeuius, in preference to ThO4 (SO2 )2, ^HjO, 

afforded by the more numerous ones of Delafontaine.4

In possible explanation of Delafontaine's high results for water Koozeboom (op. cit., p. 202) very justly remarks that because of its physical 

character the salt retains much mother liquor, and that if this be not

1 Since this was Avritten. a paper by Rammelsberg, in the Sitzb. k. preuss. Akad. Wiss., vol xxxiv, 

1880, which I had overlooked, has been brought to my attention. In it ho shows that thonranouB 

Hulphiite, formerly supposed to contain eight molecules of water of crystallization, contains iii reality 

nine, and that this salt is isomorphons with the corresponding thorium sulphate.

"Comptes Bend., 1883, vol. 96, p. 1860.

s Zoit. phys. Cheui., 1890, vol. 5, p. 198.

4 Ann. Chem., vol. 131, p. 100. The statement by Kraut, near the foot of page 687 of Gmclin-Kraut's 

Inorganic Chemistry, vol. 11, part i, is manifestly unwarranted. Ho considers the evidence in favor 

of the four-molecule HZ0 salt as insufficient and thinks the analyses affording this formula were made 

upon mixtures which might have resulted through absorption of water by the three-molecule H2O 

salt. It is strange that individuality should have been accorded to this latter salt by Chydenius and 

Cleve, which the former obtained by drying over sulphuric acid, after washing With hot water, the 

precipitate formed by boiling a weakly acid solution of the sulphates. Koozeboom is certainly correct 

in excluding this three-molecule HjO salt from the list of thorium sulphates.
30 LABORATORY REPORT, 1890-'91. [BULL. 90.

removed at a temperature above 45° C. the nine-molecule .H2O salt is 

formed from it on cooling, so that it is almost impossible not to find too 

much water. Notwithstanding numerous attempts to prepare the salt 

ThO4 (SO2 )2 ,4H2O from hot acid solutions as well as from warm neutral 

ones, I have never myself succeeded in reducing the water to four molecules, even though the mass of needles was rapidly washed with hot 

dilute sulphuric acid and then with alcohol and ether, after freeing from 

mother liquor by powerful suction on a Gooch crucible without asbestus 

felt, but my faith in the correctness of the formula with 4H2O is not 

hereby shaken. A farther possible cause of high results will appear 

from the following: The air-dried salt is said by Delafontaine to be 

thoroughly iionhygroscopic, and for a given temperature and hygrometric condition of the atmosphere it is true that no change in weight 

does occur; but if the salt is weighed from day to day, or even twice a 

day, a very marked gain or loss of weight is observed, dependin g in degree on the amount of change in the atmospheric conditions. In August and September, when hygroinetric and thermometric readings 

were often high and marked and rapid changes were not infrequent, 

this gain or loss sometimes amounted within twenty-four hours to over 

half of 1 per cent of the total weight of the salt, and the extreme change 

during those months reached 1-22 per cent. It is therefore patent that 

the formula afforded by analysis may materially depend on whether 

the salt analyzed was weighed when the weather was hot and moist or 

cold and dry.

It may not be out of place here to call attention to a possible cause 

of the frequent discrepancies noticed in the statements of different 

writers in regard to the amounts of water given off by different substances when placed over sulphuric acid in a desiccator. No one would 

deny that sulphuric acid of maximum concentration is superior as a 

drying agent to the same acid somewhat, if only slightly, diluted; but 

it is probably not known to everyone how much may depend on the 

strength of the acid used. A case in point is the following: A thorium 

sulphate containing air-dried, 15-22 per cent H2O, or 4-23 molecules, 

lost weight over concentrated sulphuric acid in a tightly closed desiccator as shown in column I, and as in column n over acid which had 

been in use in another desiccator for a considerable length of time and 

was subsequently found to have a density of 1-66. The cases are not 

rigidly comparable, perhaps, because of the different times devoted to 

the experiments, which were not carried on simultaneously, but they 

serve to illustrate the point.
HILLEBBAND 

ANI> MELVILLE.; THORIUM AND URANOTJS SULPHATES. 31

I. Acid of 1-84 sp. 

g*-

Tiiuu.

Days.

.1

3

5

9

18

Per cent.

3-80

2-78

1-37

0-22

8-17

11. Acid of 1-66 sp. 

gr.

I 

Time.

Days.

1

1

3

5

Per cent.

2-87

0-40

o-oo

3-33

This may be considered an extreme case, but it shows plainly the 

importance of using fresh acid of full strength whenever experiments 

of this kind are to be made in order that results may be properly comparable.

Similarly it is improbable that a highly hydrated substance which 

loses much of its water at 100° C. would shw as great a loss when 

dried in an ordinary air bath as in a current of dry air of that temperature.

Another point to be considered when it is desired to find the maximum amount of water that can be removed by any drying agent in a 

desiccator (which of course as a method is in general inferior to that in 

which a continuous current of dry air or other gas is passed over the 

substance) is that if many days are required for its removal in other 

words if the substance is slow to part with its moisture the later 

weighings should not be made from day to day but at ever-increasing 

intervals, otherwise a prematurely constant weight or even an increase 

may be observed. This is due to the fact that whenever the desiccator 

is opened, which must be twice for each weighing, it, at least in the 

upper part, becomes filled Avith moist air, and the substance itself may 

absorb some moisture before it can be returned to the desiccator; one 

or more days may then be required to restore the condition of equilibrium which obtained between the vapor tensions of water in the salt 

and in the air of the desiccator prior to opening the latter. Especially 

if the acid has become somewhat weakened is it possible for an 

increase to take place.

Originality is not claimed for the above observations on methods of 

drying, but it seems as if attention could not be too strongly or too 

frequently drawn to the points mentioned, which there is reason to fear 

are not always observed,

II. CRYSTALLOGRAPHIC DISCUSSION, BY W. H. MELVILLE.

The green crystals of sulphate of uranium and of the double sulphate 

of uranium and thorium described by Mr. Hillebrand are isomorphous 

and their crystallographic elements are almost identical. The angles 

between corresponding faces of the two salts differ by less than one 

degree, while their axial ratios are the same up to the second decimal
32 LABOKATORY REPORT, 1890-791. [BOLL. 90.

place. Indeed the axes plotted for the drawing of the crystals of one 

salt served for the drawing of those of the other.

The two sulphates crystallize in the prismatic (orthorhombic) system. 

The habits of the two sets of crystals are quite unlike, and by simple 

inspection no analogy would seem to exist between th.em, since those 

of the double sulphate of uranium and thorium have all the appearance of the pyramidal (tetragonal) combination of forms.

Fig. 1. Crystalline form of uranium sulphate.

On the goniometer the simple sulphate of uranium presented the 

most perfect faces, so that very accurate measurements were obtained. 

On the other hand the similar angles of the double sulphate showed 

great variations in the readings, often amounting to a difference of 40' 

from the mean value. The difficulty of preserving in artificial crystals 

the same brilliancy of faces after drying which they possess in the 

mother liquor accounts for the broad bands of these reflect signals. 

However, after its system of crystallization was identified, the mean of 

the most perfect and reliable measurements was taken.

The crystals of the double sulphate of uranium and thorium were 

often twinned, the twinning plane being parallel to (100). 1 Also individuals occurred on the faces (102) and (1$2) which were composed of 

the face (110) in combination with minute planes of the forms (111) and 

(012).

Fig. 2. Crystalline form of uranium-thorium sulphate.

The forms observed on the crystals of both salts were the same, but 

unequally developed, as the accompanying figures illustrate, in which

1 Since the original publication in the Am. Chom. Jour., vol. xiv, p. 1, of the results of the study of 

the double sulphate it has been found that the twinning is of the nature of interpenetration, and that 

the composition plane is parallel to (001) 011 those crystals in my possession.
HILLEBRAND 

AN1) MELVILLE. THORIUM AND URANOUS SULPHATES.

tlio degree of development in the originals has been preserved. Forms: 

(001), (010) always a very narrow plane whieh does not appear in the 

drawings, (110), (111), (102), (012). Measurements:

(1) Uranium sulphate.

001 A 1H

001 A 102

001 A 012

111 A 111 

111 A 110

110 A 110

102 A 102

Measured.

0 / II

70 57 00

52 13 00

33 49 00

51 09 00 

19 OB 30

54 23 00

75 34 00

Calculated.

0 ( //

70 56 30

52 10 07

33 28 14

> 1'undameiital

54 21 00

75 39 46

Axial ratio : ft : b : c 1 : 1-0478 : 2-5755

(2) Double sulphate of iiraainra and thorium.

001 A 102

001 A 012

111 A 111 

111 A 110

110 A 110

102 A 102

Measured.

o /

51 57

33 25

51 46 

19 08

55 14

76 00

Calculated.

0 / "

51 57 37

33 39 38

> fundamental

55 02 24

76 04 46

Axial ratio : ft : b : c 1 : 1-9194 : 2-5563

Bull. 90-
POWELLITE CALCIUM MOLYBDATE : A NEW MINERAL SPECIES.

BY W. H. MELVILLE.

Attention has been recently called in mining journals ^to a locality 

in the western part of Idaho known as the " Seven Devils" where 

mining operations for some time past have been actively conducted. 

" The l Seven Devils,' about 90 miles due north of Huntington and 

15 miles east of Snake river, form a high, broken chain of mountains 

nearly 9,000 feet above the sea level. The mineral zone is about 1 

mile wide by 4 miles in length." 1 The ore is worked for copper and 

silver, and is mainly the mineral bornite, a sulphide of copper and 

iron. " The formation on the west of the vein of ore is syenite and 

quartzite, while on the east wall is a soft white granite. A short distance to the east is a lime contact which extends south for some four 

miles, and forms a contact with granite. Along this contact some very 

good chimneys of ore have been discovered."

This bornite carries silver varying in quantity from 12 to 20 ounces 

to the ton. In one sample of very pure bornite Mr. E. L. Packard 

found by assay 14 ounces of silver to the ton. A sample from which I 

had separated for the most part the other mineral constituents gave 

me 15-65 ounces of silver to the ton. It was this latter fragment of 

bornite, weighing about 60 grammes, which Mr. Packard picked up 

from a dump before one of the tunnels in the mining claim called Peacock and which through this gentleman's kindness furnished the material for this paper. The specimen had evidently been exposed to 

weathering processes and had become friable to such an extent that 

between the fingers it could be crushed by slight pressure.

There were two associated minerals, one of which was identified by 

the following partial analysis as a lime alumina iron garnet. It was 

light brown, but not crystallized. It fused easily to a black glass.

Per cent. 

Loss cm ignition............................................. 0-06

SiO, ............................................*........... 38-67

AljOs....................................................... 10-08

Fe.2 03 ....................................................... 16-00

FeO ........................................................ 0-91

CaO ........................................................ .33-35

MgO....................................................... 0-77

CuO.;...................................................... trace

99-84

1 Quotations from Engineering and Mining Journal, Nov. 22, 1890. 

34
MELVILLE.J POWELLITE. 35

Crystallized dark brown garnet is found in considerable abundance 

throughout this locality. The crystals exhibit the usual combination 

of rhombic dodecahedron and tetragonal trisoctahedron.

That which proved to be the most important constituent of the specimen, about 1-5 grammes, somewhat resembled scheelite at first sight, but 

a careful study of its characters excluded that mineral species from consideration. The strong reactions for molybdenum suggested a new 

species. The mineral was well crystallized and easily detached in 

almost absolutely pure condition from its friable matrix. Angular measurements were obtained on a 

number of crystals, from which the crystallographic 

elements were calculated. The fundamental angle 

(111) A (111) was chosen because of its" great accuracy, 

the signals on the goniometer being perfectly reflected 

from these planes. Other angles Ayere read oftentimes 

between reflected signal aud reflected light, and again 

,10 between merely reflected light from the crystal faces, 

formofiioweiiite. The best crystals were about 0-04 (l'mn ) long, and 

others attained the maximum length of 0-10 inch. It Avas found that 

the crystals-belonged to the pyramidal (tetragonal) system of crystallization, and Avere closely allied in habit and development to scheelite. 

In the following table of measurement this analogy is shown.

a : c

Povrellite.

1:1-5445

Between normals. Observed, j Calculated.

111A11L

111 A 001

111 A 111

101 A 101

101 A 111

O 1 o /

49 12 ; fundamental.

05 24

79 5GJ

05 55

40 14

05 24

80 1

05 51

40 1

Scheelite.* 

1:1-5369

o /

49 27

05 16

79 50

06 0

39 58

* Dana's System of Mineralogy, 1883, p. 005.

From this comparison of angles and axial ratio it is evident that 

sharp and accurate observations must be obtained in order to distinguish by crystallographic means alone between these two species. 

Many crystals were examined and many trials were necessary before 

any difference in these angles from those of scheelite could be made out.

The following forms were observed:

(001) ct. a : cr. a : c

(111) a : a : c 

(101) a : oc a : c 

(110) a : a : oc c

Small rudimentary planes appear on some crystals at the lower portion of the combination edges (111) (101), thus suggesting hemihedrism
36 LABORATORY REPORT, 1890-'91. [BULL. 90.

as in scheelite. Indeed, the curved surface which often replaces these 

edges, giving the appearance of fused edges, adds greatly to the evidence in favor of this supposition.

No cleavage planes could be developed by mechanical means, yet 

occasionally fragments exhibited interrupted planes similar to cleavage 

surfaces. Hardness less than scheelite, about 3-5. Sp. gr. 4-52G, mean 

of two determinations. Color yellow with a decided green tinge. Luster resinous. Crystals semitransparent. Brittle. The blowpipe characters are those ordinarily given under molybdates and tungstates, 

although the reactions of molybdenum in this case obscure those of 

tungsten associated with it. The mineral fuses at about 5 to a gray 

mass. Decomposed by nitric and hydrochloric acids.

With powellite was associated an olive-green substance which without doubt resulted from the decomposition of calcium molybdate, perhaps by water holding carbonic acid in solution, whereby molybdic 

ocher was formed.

The following analysis shows the unusual replacement of apart of the 

molybdic acid by tungstic acid. Eose's method of separating these acids 

was adopted, and abundant tests proved the purity of the respective 

products of separation. Molybdenum trisulphide was collected by 

reverse filtration and aliquot portions were taken for reduction. The 

molybdenum was weighed first as disulphide, and this weight was 

checked by reduction to metal in hydrogen gas by strong and long continued ignition. Mercurous tungstate was precipitated, then ignited, 

and tuugstic acid was finally weighed.

Anaylals of powellite.

Mo03 . ......................

WO.........................

CaO...... ..................

MgO.. ......................

FeA---- ...................

A1A-- .....................

CuO ........................

S-. .........................

Per cent.

58-58

25-55

1-65

99-47

CaO required.

22-79

25-28

Calcium molybdate has never before been observed in nature, and 

although the mineral under discussion contains some calcium tungstate according to analysis a little less than one molecule to eight 

molecules of calcium molybdate yet the molybdate is now established 

as a species. It fills a gap heretofore existing in the series of isomorphous minerals of which scheelite is the type. If the natural molybdate and tungstate of lime have the same molecular volume as is most
MELVILLE.] POWELLITE. 37

probable, then the sp. gr. of pure CaMoO4 should be 200-:- 46-9=4'267 

if the molecular volume, 288 -f- 6-14 = 46*9, is true for scheelite. By 

means of the equation for the determination of the sp. gr. of one constituent of a mixture containing two substances of which one is known, 

the sp. gr. of CaMoO4 is 4-3465 assuming the sp. gr. of CaWO4 to be 

6-14 and that of the mixture 4-520 (sp. gr. of powellite). This close 

agreement in these two calculations of the sp. gr. of CaMoO4 is an interesting and important confirmation of the chemical and physical data 

which are given above.

When this investigation was nearly completed my attention was 

called to a recent paper by H. Traube, 1 in which was discussed the influence of certain varying quantities of molybdic acid in scheelite upon 

the.physical constants, namely, sp. gr. and axial ratio. The following 

scheme is interesting in that it illustrates those variations which different proportions of isomorphous mixtures of OaW04 and CaMoO4 produce. No mathematical law seems to exist which will express these 

transitions.

%Mo03 -- .........

Sp.gr.............

CaMoO4 .

72

4-267 

1 : 1-5458

Powellite.

58-58

4-520 

*1 : 1-5445

Sell eel He.

Southwest; 

Africa.

c 8-09 

\ 7-63 

5-90

Ziniiwald.

1 2

| 8-23 1-92

5-88 0-OG 

1 : 1-5349

CaW04 .

0

6-14 

1 : 1-5315

* Hiortdahl, Zeitsch. Kryst. u. Min., 1887, vol. 12, p. 413.

I take pleasure in naming this new mineral species in honor of Maj. 

J. W. Powell, Director of the United States Geological Survey.

1 Nones Jain-bach., 1890, Boil. Mil. 7, Heft 2.
MINERALOGICAL NOTES.

BY W. H. MELVILLE.

NATROLITE FROM MAGNET COVE, ARKANSAS.

The specimen of natrolite here described, from Magnet Cove, Arkansas, is associated with feldspar, while in the mass of the natrolite occur 

crystals of regirite. From certain cavities crystals were selected which 

were adapted for measurements. The crystals were often acicular; 

others were stouter and terminated with brilliant planes. The general 

mass was compact and exhibited broad and perfect cleavage planes. 

The fusibility appeared somewhat higher than ordinarily given for 

natrolite, but thin splinters fused to a colorless bead. The sp. gr. 2-261 

was determined.

The long terminated prisms proved to be triinetric and were built 

up of the forms (010), (100), (110), (111).

The following angles were read:

(110) A (HO) 

(010) A (110) 

(lll)A(Hl) 

(111) A (Til)

(110) A (Hi)

88 51

244 16

36 56

37 23

63 18

45 30

36 40

37 20

63 20

The angle (110) A (1TO)=SS° 51' was best obtained from cleavage 

planes which were found on the crystal, but the mean of all readings 

on the corresponding crystal planes gave 88° 44'.

Analysis.

H^O at 100° C.... ...........

H2 0 at 250° C. ...... ........

H20at300° 350° C. .........

H20 over blast. .............

SiOs...... ..................

Al,03 ....... ................

Per cent.

0-07

0-19

3-42

5-95

0-00

47-50

26-82

FeO ........................

CaO ........................

MgO .......................

Na,0 .......................

Total.................

Per cent.

0-20

0-13

0-09

15-40

99-83

38

1 The second column of angles was taken from Daua's Mineralogy.

2 Approximate.
MELVILLE.] MINERALOGICAL NOTES. 39

TOURMALINE FROM NEVADA COUNTY, CALIFORNIA.

' An uncommon form of tourmaline occurs in some localities of Nevada 

county, Cal. It is radiated and is composed of separable needles 

which show all the phenomena of hexagonal crystals under polarized 

light. The needles appear to cleave at right angles to their longer 

direction, or at all events the cross fracture has all the appearance of 

cleavage. A mass of these needles possess a dark brown color and 

silky luster, but singly they are transparent and almost colorless by 

transmitted light. The mineral fuses very easily to a light brown 

glass which is nonmagnetic. The specific gravity was found to be 

3-065.

In the following analysis the boracic acid is determined by difference, 

although it was found, according to Marignac's method, to be much 

less than appears in the summary. The state of the iron was not determined. The analysis is therefore incomplete. Indeed all work upon

the mineral ceased after identification.

Analysis.

Loss at 100° C ........................

SiO*. .................................

Alj03 ---- .............................

FoA .................................

CaO. .................................

MgO..................................

K20 ..................................

~F.. ...................................

c Per cent.

0-02

3-04

0-47

36-40

33-64

3-13

1-51

10-01

0-12

2-49

0-74

8-74 direct. 6-52

100-31 98-07 

 31 -31

100-00 97-76

The material analyzed was collected about two miles northwest of 

Colfax.

SPESSARTITE GARNET FROM LLANO COUNTY, TEXAS.

The following analysis of a yellow-colored mineral from Llano county, 

Texas, gave very closely the composition of spessartite garnet. It appears that the iron is in part replaced by calcium and magnesium, and 

hence it is very probable that the iron in this mineral exists in the protoxide state, although it could not be separately determined owing to 

the admixture of a little black oxide of manganese. The mineral was 

massive and was associated with quartz, a little magnetite, and black 

oxide of manganese. The silica was separated before analysis.
40 LABORATORY REPORT, 1890-'91. 

Analysis.

[BULL. 90.

SiOj ........................

p r»

Ti02 ...... ..................

kltOa ........ ...............

p^o,*...... ................

Per cent.

0-03

0-36

35-93

18-08

4-60

MnO...... .................

PaO

BaO ........................

M£jO........... .............

Per cent.

31-77

8-48

0-69

0-17

100-11

*FeO corresponding=4-39. 

BISMUTHINITE FROM SINALOA, MEXICO.

A large deposit of bismuthinite occurs in the Rosario mining district, 

in the state of Sinaloa, Mexico, and it has been recently opened for the 

production of bismuth as well as for the recovery of silver and gold 

which the ore carries. An assay of carefully selected material was 

made, showing the contents of silver and gold to be 65-5 ounces and 

0-25 ounce to the ton. This sulphide of bisumuth is associated with 

considerable chalcopyrite. and quartz and occurs in large brilliant 

blades with the broad cleavage so characteristic of bismuthinite. Its 

specific gravity is 6-624.

Analysis.

Bi ................

Pb...... ..........

Cu...... ..........

Fe...... ..........

s. ...... ..........

Per cent.

72-90

G-03

°1-C7

' 0-35

18-11

0-63

99-09

S. required.

16-82

0-91)

0-84

0-20

38-79

The sulphur comes out too low in the analysis because it was determined in the filtrate from the carbonates precipitated by potassium 

carbonate, which does not wholly decompose bismuth sulphate.
NEW ANALYSES OF ASTROPHYLLITE AND TSCHEFFKINITE.

BY L. G. EAKINS.

I. ASTROPHYLLITE.

Near the noted cryolite locality at St. Peters dome, in the Pike Peak's 

region of Colorado, there was found some years ago an unusually fine 

lot of as trophy] lite, and in such a pure condition that it was thought 

a new analysis would be not without interest, notwithstanding the fact 

that material from the same region had already been analyzed by Kouig. 1

This astrophyllite occurs in large, brittle, micaceous blades, golden» 

to brownish yellow in color, and perfectly free from admixed minerals, 

such as zircon, the only foreign matter being on the ends or sides of the 

blades which were in contact with the containing rock, so that pure 

material for analysis Avas readily obtained. In this analysis the zirconia 

was separated by a modification of the hydrogen peroxide method and 

weighed directly, being subsequently identified qualitatively. Fo comparison Avith this analysis, those made by Konig and by Backstrom2 

are added to the table below, Kb'nig's being the one previously referred to, of material from the same region, and Backstrom's of the 

Eikaholmen mineral.

TaA--- ..-.-..-..

SiO; ..............

Ti0.2 ....... .......

ZrO*...-..........

Fe^Oj.. ...........

Al-A-- ...........

FeO ..............

MnO...... ........

CaO ..............

MgO...... ........

'KjO ..............

NaaO .............

H20. .............

Eakins.

Analysis.

0-34 

35-23 

11-40 

1-21

3-73

29-02 

5-52 

0-22 

0-13 

5-42 

3-C3 

4-18

100-03

Molecular ratio.

 001 

 587 

 143 

 010 

 024

 403 

 078 

 004 

 003 

 058 

 059 

 232

Konig.

Analysis.

0-80 

34- G8 

13-58 

2-20 

C-5G 

0-70 

20-10 

3-48

0-30 

5-01 

2-54 

3-54 

CuO -42

99-91

Molecular ratio.

 002 

 578 

 170 

 018 

 041 

 007 

 362 

 049

 008 

 053 

 041 , 

 197 

 000

Biuik.stroin.

Analysis.

33-02 

11-11

3-05

2-53

0-98

21-76

11-96

1-26

0-92

5-78

2-77

3-47

F 0'97

100-18

Molecular ratio.

 550 

 139

 030

 016

 009

 302

 169

 023

 023

 062

 045

 393

 051

1 Proc. Am. Phil. Soc. Philad., 1877, vol. 10, p. 509.

2 Given by Brogger in Grotli's Zeitsclirift, volt 16. W. C. Brb'gger, Die Mineralien der Syenitpeg. 

matitgiiuge, etc.

41
42 LABORATORY REPORT, 1890-'91. [BULL. 90.

From a discussion of these analyses of Backstrom and Konig, Brogger deduces the general formula E//4E,/4Ti(SiO4 )4 for astrophyllite. It 

will be seen that my analysis closely confirms this formula, agreeing 

with it better, in fact, than those from which it was derived. Calculating the small amount of ferric oxide present in with the E" group, 

the molecular ratios of my analysis give the following elementary proportions :

Sl587O2

This reduces to

which is close to E//4E/4Ti(SiO4 ) 4 ; the excess of the E' group is presumably due to the percentage of water being somewhat too large ; this 

may result from incipient alteration of the mineral, which may also be 

the cause of the variation in color.

II. TSCHEFFKINITE.

A fragment of this rare mineral was last year sent to the National 

Museum by Mr. Horace M. Engle, of Eoanoke, Virginia. And upon its 

identification he very kindly presented all at his disposal for the purpose of investigation; in addition to some small fragments there was 

one large mass, which before breaking weighed over 3£ kilograms, most 

of it now being in the museum collection. - It was found in Bedford 

county, Virginia, a point considerably farther south than the locality of 

the material analyzed by Price.1 The various pieces of this tscheff kinite 

when found were all more or less rounded nodules, with a superficial 

brownish yellow ocherous coating, evidently an alteration product, 

which at some later date may be made the subject of investigation to 

endeavor to determine the method of alteration. The beginning of this 

alteration was also seen in the numerous fissure planes developed in 

breaking up these nodules. Examination of a fresh surface showed a 

distinctly banded structure of lustrous black and dull black material, 

the bands varying from mere lines to over 5 millimeters in width. As 

well as could be these two differently appearing substances were separated and each analyzed by itself; such separation, however, was only 

approximate, as under a magnifying glass it was seen that each band 

contained veins of the other. Analysis I is that of the lustrous part 

and II that of the dull.

Duplicate determinations confirmed these specific gravities, the seemingly more altered one being the higher. The action of acids on the 

powdered materials shows a marked difference, the lustrous portion 

being completely decomposed in a few minutes by warm and moderately 

strong hydrochloric, sulphuric, or nitric acids, while an hour or more 

was necessary to decompose the dull portion under similar conditions.

1 E. C. Price, Am. Chem. Journal, Jan., 1888.
EAKINS.] ASTEOPHYLLITE AND TSCHEFFKINITE. 43

These analyses show that the two bands are practically identical in 

composition, the dull being somewhat more hydratecl. The molecular 

ratios seein to lead to no definite or satisfactory formula, a result 

quite in accordance with the evidence furnished by the microscopical 

examination of sections. For this purpose chips were taken showing 

both bands, but as in the case of the chemical analysis, they were seen 

to be practically the same.

TaA...... .................

SiOj ........................

TiO........ ..................

ZrO,. ....................... 

ThO, ......... .............

(Y,Er) 2O3 ..................

(La, Di)A-.-- -- -...-.- ..

CojOs....... ................

A1203 -. .....................

Fo303 ......... ..............

FoO ........................

CaO ........................

MgO........................

NajO .......................

H20 ........................

I.

Analysis.

0-08 

20-21 

18-78 

trace ( ?) 

0-85 

* 1-82 

19-72 

20-05 

3-60 

1-88 

C-91 

4-05 

0-55 

0-06 

0-04

99-50

Molecular ratio.

 337 

 235

 003 

 006 

 059 

 001 

 035 

 012 

 096 

 072 

 014 

 001 

 052

4-33 at 27°

II.

Analysis.

0-08 

21-49 

18-99 

Iraco (?) 

0-75 

tl-64 

17-10 

19-08 

3-G5 

2-89 

5-92 

5-24 

0-48 

0-04 

2-06

99-47

Molecular ratio.

.358 

 237

 003 

 005 

 052 

 058 

 030 

.018 

 082 

 094 

 012 

 001 

 114

4-38 at 22°.2

* Molecular weight=308. t Molecular \veiglit=312.

I am indebted to Mr. Whitman Cross, of the IT. S. Geological Survey, 

for the following notes on the thin sections:

The sections consist mainly of reddish and yellowish brown transparent amorphous substance, apparently the original material; this is traversed in all directions 

by cracks, from which there has proceeded a decomposition producing a reddishbrown opaque ocherous matter, which nils the cracks and replaces the original material so that ^n certain spots there is now merely a network of the two substances. 

In each section there are two parallel bands of secondary minerals, nothing corresponding to which was detected in the chips before the sections were made. These 

bands consist chiefly of two colorless minerals, the more abundant occurring in 

irregular grains closely resembling calcite in strength of refraction and double 

refraction; the other occurs in rounded grains and is probably sphene. In addition 

to the two colorless minerals in these bands, there also appear two brownish substances, one of which has distinct prisms, without terminal planes, shows strong 

pleochroism, and its absorption parallel to the vertical axis is so strong as to make 

it opaque, while at right angles to this axis it is yellow-brown. More abundant 

than this prismatic mineral is one occurring in apparent flakes of reddish-brown 

color; it is doubly refracting, but not strongly pleochroic, and can not be identified 

with any of the substances already mentioned. Adjacent to these bands, and replacing the amorphous material to varying distances, is still another substance, in general appearance similar to the prismatic mineral, but evidently different as it shows
44 LABOEATOEY EEPOET, 1890-'91. [BULL. 90.

no very marked absorption. This mineral is also strongly pleochroic, varying from 

yellow-brown to chestnut-brown. All of it in the sections seems to have a uniform 

crystallographic orientation, the cause of this uniformity not being apparent. Its 

relations to the amorphous substances are similar to those which I have observed 

in several instances between crystalline alJanite and the amorphous variety.

The microscopical examination having shown this tscheff kiiiite to be 

such a mixture, it became desirable to examine others in the same way.

The only one available for this purpose was that analyzed by Price, 

a specimen of which is in the National Museum collection. This specimen has the same general appearance and banded structure as my 

own. Chips were taken from it for sections, which Mr. Cross examined and found to be in. every respect similar to the other, about the 

only noticeable difference being in Price's material a somewhat greater 

development of the opaque ocherous decomposition product of the 

transparent amorphous substance than in mine, and a lesser development of the colorless minerals.

Taking into consideration the results of this work, and the manifest 

contradictious of most of the earlier analyses, it seems reasonable to 

conclude that, unless one of the earlier analyses can be shown to have 

been made on pure material, the so-called tscheff kinite is not a mineral 

in any strict construction of the word, but merely a mixture; .the structure of the chemically complex body or bodies evidently its basis being 

a problem to be elucidated in the future when purer material may be 

found.
TWO NEW METEORITES.

BY L. G. EAKINS.

I. METEORIC IRON FROM PULASKI COUNTY, VIRGINIA.

The material for this analysis was furnished by Mr. G. F. Kunz, in 

whose possession the original mass, weighing'about 30 pounds, now is. 

This iron calls for no special comment in itself. The specific gravity is 

7-95 at 23°.

Analysis.

Fe.......................................................... 93 -59

Ni.......................................................... 5 56

Co.......................................................... 0-53

Cu ......................................................... trace.

P........................................................... 0-27

s........................................................... o-oi

Si.......................................................... trace.

99-96 

II. STONE FROM WASHINGTON COUNTY, KANSAS.

The material for this work was also furnished by Mr. Kunz. A detailed account of its fall has been published by Mr. F. H. Snow, m 

Science, July 18,1890. This stone fell on June 25,1890, and was noted 

by several observers "by the sound it made on falling, the actual fall 

also being seen by at least one; on striking the earth it buried itself 

out of sight in a hole about 4 feet deep.

The stone when taken up weighed 184 pounds, and was cracked in 

two.

In general appearance it is grayish black, with white particles scattered throughout, these being probably a pyroxene. Particles of troilite and of iron were also visible.

The specific gravity of the mass was 3-49 at 21-60.

As is usual \vith this class of stones the metallic portion was extracted 

and analyzed by itself; the portion from which this was taken then 

being treated with dilute hydrochloric acid, this dissolving troilite and 

oliviue.

The analyzes are as follows:

45
46 LABORATORY REPORT, 1890-'91. 

Metallic particles.

[BULL. 90.

Fe.

Ni. 

Co.

86-76

12-18

 83

99-77

Material left after extracting metallic particle*.

SiO, ........................

A1.Q........... .............

ri_ r\

FeO ........................

NiO.. ...... ................

CoO............ .............

MnO... .....................

CaO ........................

MgO...... ..................

KjO...... ...................

NajO............ ............

S ...........................

Soluble in HC1.

Analysis.

19-15

16-15 

 34 

trace. 

 17 

 06 

18-31

1-97

56-15 

 99

55-16

Less 

troilite.

19-15

11-71 

 34 

trace. 

 17 

 06 

18-31

49-74

Calculated 

to 100 

per cent.

38-50

23-54 

 69 

trace. 

 34 

 12 

36-81

100-00

Insoluble in HC1.

Analysis.

24-29 

1-95 

 64 

5-41

trace. 

1-84 

10-10 

 12 

 80

45-15

Calculated 

to 100 

per cent.

53-80 

4-32 

1-41 

11-98

trace. 

4-08 

22-37 

 27 

1-77

100-00

It will be seen that in the analysis of the part soluble in hydrochloric 

acid all the sulphur found has been calculated as troilite. Taking this 

amount, the metallic particles found, and the relative proportions of 

the silicates, the approximate composition of the mass is found to be:

Nickel iron.................................................. 7'7

Troilite...................................................... 5-0

Silicates soluble in HC1...................................... 46'0

Silicates insoluble in HC1................................... 41-5

100-2
ON THE ACTION OF PHOSPHORUS OXYCHLORIDE ON THE ETHERS 

AND CHLORHYDRINES OF SILICIC ACID.

BY H. N. STOKES.

That silica can combine with other acids, forming mixed anhydrides, 

has long been known, and several such bodies have been described. 

Friedel and Ladenburg 1 obtained the tetra-acetyl derivative Si(O.OO. 

CH3 )4 -by treating silicon tetrachloride with acetic acid or anhydride. 

Friedel and Crafts 2 obtained Si(OC2H5 )30,CO.CH:3 from ethyl orthosilicate and acetic anhydride. Hautefeuille and Margottet3 described a 

crystalline compound, SiO2 .P2O5, formed by fusing amorphous silica 

with rnetaphosphoric acid.

By the action of phosphorus oxychloride on silicic ethers and their 

chlorine derivatives, I have obtained bodies which consist of phosphoryl 

chlorides, in which the chlorine is partly replaced by a residue of silicic 

acid, and which are therefore chlorides of silicophosphoric acids.

Phosphorus oxychloride was caused to react upon orthosilicic- ethyltrichlorhydrine, Si013 .OC2H5 , hoping thereby to obtain the silicon 

oxychloride described by Friedel and Ladenburg 4 and by Troost and 

Hautefeuille: 5

3SiCl3 .OC2H5+POCl3 =(SiCl3O)3PO+3C2H5Cl, 

and

2(SiCl3O) 3PO=3Si20016+P2O5 .

The experiment proved that this reaction does not take place.

If the trichlorhydrine be heated in a sealed tube with an excess of 

phosphorus oxychloride, no reaction is apparent below 175°, the contents remainin g perfectly clear. If the temperature be kept at 180-200°, 

a white amorphous substance is soon formed, which is sufficiently porous 

to absorb all the liquid products. After two to three hours' heating 

the tube is opened, when ethyl chloride escapes in large quantities. 

On placing the tube in an air bath, heated at about 150°, and connecting it Avith a condenser, a large amount of liquid may be collected. 

The solid remaining in the tube may then be freed from excess of phosphorus oxychloride by passing a current of dry air over it by means of a 

capillary.

1 Aim. Chcm. (Liel)ig), vol. 140, p. 174. 4 Ann. Chern. (Licbig), vol. 147, p. 355.

2 Ann. chim. phys. [4], vol. 9, p. 47. 6 Ann. chim. pliys. [5], vol. 7, p. 465.

3 Conipt. roiul., vol. 90, p. 1052.

47.
48 LABORATOKY REPORT, 1890-91. [BULL. 90

The liquid, on fractioning, is readily separated into phosphorus oxychloride (boiling at 110°) and silicon tetrachloride (boiling at 57°-61°), 

though much of the latter is lost, being carried off by the ethyl chloride, 

which is abundantly held in solution. The product obtained after six 

distillations was analyzed.

.

Si...........................

Calculated 

for SiCl4 .

10-52

Fouud.

10-24

The view with regard to its nature was confirmed by converting it 

into ethyl orthosilicate (boiling at 165-5°). As the liquid passed over 

entirely below 112°, no silicon oxychloride was formed, and no substances other than those mentioned could be detected. Analyses of 

the solid substance gave 

latert 

S 06C12 .

10-92

24-15 

27-59

Found.

I.

10-17

25-16 

27-33

II.

10-06

25-11

The agreement is only approximate, as the substance could not be 

purified in any wayj and on heating too long or at too high a temperature, when drying, phosphorus oxychloride is slowly given off. It is 

possibly a mixture of substances, in the formation of which the one 

supposed represents one stage. If heated above 200° phosphorus oxychloride is given off, and at red heat, phosphorus pentoxide; and the 

residue, left at a white heat, consists of amorphous silica imbedded in 

a vitreous substance, probably the compound SiO2 .P2O5 of Hautefeuille 

and Margottet. The loss on heating corresponds to the equation 

= 3SiO2 + 3(SiO2.P2O5 + P2O5 .

Calculated.

49-01

Found.

The formation of the substance, which, for reasons given below, may 

be designated as silico-pyrophosphoryl chloride, is most simply expressed 

by the equation 

4SiCl3 (OC2H5 ) + 2POC1., = 3SiCl4 + SiP2O6Cl2 + 402H5C1.

Silico-pyrophosphoryl chloride is a very bulky substance, resembling 

the lightest form of amorphous silica. It may be obtained perfectly 

colorless, but is usually more or less colored by organic matter, formed
STOKES.] ' CHLORIDES OF SILICOPHOSPHORIC ACID. 49

by secondary reactions, when heated too high. It is extremely hygroscopic, and gives off hydrochloric acid instantly when exposed to moist 

air. It is readily soluble in absolute alcohol, a proof that it contains 

no free silica. The .alcoholic solution, which probably contains an ether 

of silico-phosphoric acid, may oe evaporated nearly to dryness or heated 

any length of time at 150° without decomposition. On heating at 225° 

it soon deposits transparent, gelatinous silica. The solution in alcohol 

is attended with considerable rise of temperature. The substance is 

insoluble in ether. If cold water be poured on the fine powder it readily dissolves, with the exception of a few flakes of silica; but if first 

moistened, or if in lumps, most of the silica remains undissolved. The 

best Avay to get a clear aqueous solution is to dissolve in a little alcohol 

and then to dilute with water. The reaction with water alone is somewhat violent. The aqueous solution may be kept a long time indeed, 

may be strongly concentrated on the water bath but on evaporation 

to dryness a vitreous mass is left, from which water extracts phosphoric 

acid only.

All attempts to prepare salts of silico-phosphoric acid have failed. 

Ammonium carbonate precipitates gelatinous silica. If the cold aqueous solution, prepared as described above, be acidified with nitric acid, 

excess of silver nitrate added, and filtered from silver chloride, a clear 

solution is obtained. If to this be added, drop by drop, dilute ammonia, 

a white precipitate is formed, which at a certain point changes to yellow. The analysis of the white substance (dried at 100°) gave 

Ag .........................

Calculated 

for Ag4P2 07 .

71-17

Found.

 71-25

The yellow precipitate proved to be merely silver ortho-phosphate. 1 

The filtrate from the silver salts gives an abundant precipitate of silicic 

acid when warmed with ammonia. The magnesia precipitate also 

shows the characteristic reaction of magnesium pyr'o-phosphate, dissolving in acetic acid when precipitated in the cold, ancl being reprecipitated from this solution on boiling.

The substance is therefore a derivative of pyro-phosphoric acid, and 

the formation of some ortho-phosphoric acid may be explained by the 

decomposition of the former, pyro-phosphoryl chloride dissolving in 

water with formation of ortho-phosphoric acid.2

Heated with phosphorus pentachloride at 100°, silico-pyrophosphoryl

1 The reaction deacribed above affords a convenient method for separating, at least approximately, 

ortho- from pyro-phosphoric acid. A solution of the acids or their soluble salts is acidified in the cold 

with nitric acid and silver nitrate added in excess. On adding dilute ammonia, drop by drop, all the 

pyro-phosphoric acid is precipitated before any of the ortho-phosphoric acid comes down. At this 

point a single drop of ammonia gives a yellow tinge to the precipitate, which a drop of dilute nitric 

acid causes to-disappear, Jf tUo liquid be now filtered, all the pyro-phosphoric acid will bo in the precipitate and all the p_r.thq:p,hqpphoric acid in the filtrate. The reaction is so sharp that it might possibly he used to separate £ljo acids quantitatively.

? Micliaelis: Her. d. deutgcl|. cljem, Gea., vo}, 4, j). 707,

Bull, 90 4
50 LABORATORY REPORT, 1890-91. [BULL, i

chloride is readily and quantitatively converted into silicon tetrachloride and phosphorus oxychloride:

SiP2OcCl2 + 4PC13 = Si014 + 6POC1>

The tetrachloride was isolated, and expectations with regard to its 

nature were confirmed on converting it into the ether (b. p., 165-5°). 

No silicon oxychloride could be obtained. If heated with an insufficient amount of phosphorus pentachloride, the excess remains apparently unchanged.

The conversion of a derivative of silicic acid into silicon tetrachloride 

at so low a temperature has not been hitherto observed. E. Weber 1 

obtained the tetrachloride and phosphorus oxychloride by passing the 

vapor of phosphorus pentachloride over silica at a red heat. As the 

pentachloride is completely dissociated at 300° into trichloride and 

chlorine, the reaction is due to the action of chlorine, combined with 

the reducing action of the trichloride 

SiO2 + 2PC13 + 2012 = SiCl4 + 2POC13 

which is analogous to the old method of preparing the tetrachloride 

SiO2 + 20 + 2C12 = SiCJ 4 + 2CO.

As I have convinced myself, phosphorus peutachloride does not act on 

amorphous silica (dried atlOO0 ) even at 250°, further than to dehydrate it.

The action of a smaller quantity of phosphorus oxychloride on the 

trichlorhydrine is similar. Three-molecule trichlorhydrine and onemolecule oxychloride, heated at 180°, gave ethyl chloride, silicon tetrachloride, and a solid product completely soluble in alcohol and water, 

the composition of which differed, however, from that of the substance 

above described. (Found: Si, 15-25; P, 22-30; 01, 14-13.)

The action of an excess of phosphorus oxychloride on the chlorhydrines Si012 (OC2H5) 2 and SiCl(OC2H5 ) 3 is essentially similar. At ISO2000 a solid substance is formed, with much ethyl chloride and silicons 

tetrachloride.^ The amount of the tetrachloride is directly, and that of: 

the solid inversely, proportional to the amount of chlorine in the chlorhydrine. In each case the tetrachloride was isolated in a state of 

approximate purity and converted into the ortho-ether, boiling at. 

165-5°. No other volatile substances could be detected. The solid 

body was completely soluble in alcohol and, in brief, showed all the 

properties above described as belonging to silico-pyrophosphoryl chloride. The analysis of tiie product from SiCl 2 (OC2H5 )2 gave 

Si...........................

P...........................

Calculated

for SiP2 06Ch.

10-92

24-35

Found.

T.

1.1-08

24-03

II.

24-91 !

1

I Ann, d^r Phys., Pugg., vol. 112, p. 019.
STOKES.] CHLORIDES OF SILICOPHOSPHORIC ACID. 

The product from. SiCl(O02H5 ):) gave 

51

Si.......... ................

P ...........................

Cl ..........................

Calculated 

for SiP2 06Cl2 .

i n-Q9

24-15

Found.

10-15

24-54

The results, as before, are only approximate 5 but, it must be remembered, the body loses phosphorus oxychloride slowly on heating, and 

only the crude product could be analyzed. The reactions in these 

cases are:

4Si012 (OC2H5 )2 + 4POC1, = 2Si014 + 2SiP2O6C1 2 + 802H5C1, 

4SiCl (OC2H5 ) 3 + 6POC13 = SiCl4 + 3SiP2OG Cl2 + 12C2H5C1.

Orthosiliric ether, Si(OC2H5 ) 4 , was heated with excess of phosphorus 

oxychloride for two hours at 180°-200°. The tubes contained a solid 

substance and ethyl chloride. On distilling off the excess of oxychloride and decomposing it with water only a trace of silica was left after 

evaporation, showing that practically n6 volatile silicon compound was 

formed. The solid, the properties of which were in every respect identical Avith those of the body above described, gave'on analysis 

Si................

P.................

Cl ................

Calculated

for SiP206Cl2 .

10-92

24-15

I.

9-92

25-52

29-66

Pound.

II.

10-05

111.

10-21

25-84

The reaction is. therefore, represented by the equation 

Si(OC2H5 )., + 2POC13 = SiP2O6Cl2 + 4C8H5C1.

The constitution of the silico-phosphoryl chloride is possibly very 

complex. The simplest constitutional formula, deduced from the last 

 equation, would be 'O

>POC1

Si- O 

O 

O

>POC1

but as this would give no pyro-phosphoric acid on decomposition with 

water? we must assume that it is

O.PO.C1
52 LABORATORY REPORT, 1890-'91. [BULL. 90.

or a polymer eontaining the group O.PO.O.PO.O , which makes 

it a derivative of metasilicic acid. The cause of the formation of silicon 

tetrachloride from the chlorhydrines is not clear. It is obviously not 

due to a direct replacement of ethoxyl by chlorine, for then it should be 

obtained in the same amount from each chlordydrine, or from the ether; 

whereas the latter does not give it, and the amount obtained from the 

former is proportional to the amount of chlorine they already contain. 

Besides, no phosphoric ethers are formed. Nor does the supposition 

explain the formation of silico-pyrophosphoryl chloride in quantities 

inversely as the amount of chlorine. A possible explanation is the following : The chlorhydrines1 are formed by heating mixtures of orthosilicic ether with silicon tetrachloride, o'r of either of these with other 

chlorhydrines, that one being formed in largest amount which corresponds in composition to the mean composition of the mixture; for 

example 

3Si(OC2H5 )4 + SiCi; = SiCl(6c2H5 ) 3 .

2Si013(002H5 ) + Si(OC2H5)4 = 3Si012 (OC2H5 )2.

»

These reactions take place below 200°; partial dissociation occurring, 

the products reuniting to form that body which tends to give the liquid 

a homogeneous composition. Doubtless the reverse process takes place 

at the same time; for example 

4SiCl(OC2H5 ):! = 3Si(OC2 H5 )4 + SiCl4 ;

and if phosphorus oxychloride be present which, as just shown, destroys the ether -this can go on until all the chlorhydrine has oeen converted into ether and tetrachloride. This explanation is simple enough, 

but, as shown by the action of phosphorus oxychloride on disilicic 

chlorhydrines, the actual process is possibly more complicated.

By heating a mixture, of trichlorhydrine, phosphorus and iodine, a 

solid of similar properties was obtained, and silicon tetrachloride was 

formed. The reaction was not followed further.

ACTION OF PHOSPHORUS OXYCHLORIDE ON DERIVATIVES OF DISILICIC

ACID. 

Hexethyl disilicate,2

0 Si(002H5 ) 3 

Si(OC2H5 ) 3 '

was heated with an excess of phosphorus oxychloride in sealed tubes 

at 180-200° for two or three hours. The tubes contained a white solid, 

outwardly resembling silico-pyrophosphoryl chloride and much ethylchloride. No volatile silicon compound was formed. The solid resembled in its general properties the one described. It was completely 

soluble in alcohol, and therefore contained no free silica. The solution

1 I'riedel and Crafts: Ann. cbini. phys. [4], vol. '.), pp. 11, ]4, 1§, 

«Ibid, p. 24,

 A
CHLORIDES OP SILICOPHOSPHORIC ACID. 53

gave the reactions of pyro-phosphoric acid. It differed markedly in 

composition from the orthosilicic derivative, the analysis giving 

j Calculated for 

 Sil'AClj,.

1 Si...........................' 10-92

P. ..........................' 24-15

Cl. ......................... 27-59

Found.

17-03

21-04

This corresponds to no probable formula, but contains 4 atoms Si to 

5 atoms P, instead of 1 atom Si to 2 atoms P. Phosphorus peutachloride converts it readily (at 100°) into silicon tetrachloride and phosphorus oxychloride. No silicon oxychloride is formed,- the product 

passing over entirely below 112°. The tetrachloride was isolated and 

converted into the tetrethyl ether (boiling at 165.5°).

The ease with which the ortho-chlorhydrines give, with phosphorus 

oxychloride, silicon tetrachloride, led to an analogous experiment with 

 the disilicic chlorhydrines, in the hope that in this way silicon oxychloride 

might be obtained. On the above hypothesis, we should have, in the 

presence of phosphorus oxychloride, the following reaction:

SiCl3 SiOl, 

GO< Si012 (OC2H5 ) =50<

Si(OC2H5 ) 3 .

and analogous reactions with the other chlorhydrines.

The disilicic chlorhydrines, which have not hitherto been prepared, 

are formed by heating disilicic ether with an excess of silicon tetrachloride for several hours at 200°. A gradual exchange of ethoxyl and 

chlorine occurs, disilicic chlorhydrines and ortho-silicic trichlorhydrine 

being formed. After distilling off the latter, the residue is again heated 

with silicon tetrachloride, whereby the conversion is carried further. 

In this way a mixture of disilcic chlorhydrines was obtained, which, 

after freeing from all ortho-silicic compounds by repeated distillation, 

boiled at 170-220°. A chlorine determination showed that it contained 

the equivalent of 65 per cent Si2O016. No attempt was made to isolate 

any of these chlorhydriues, as no less than eight are theoretically possible, and it was presumed that they would all act in the same way 

toward phosphorus oxychloride. The mixture was heated with excess 

of phosphorus oxychloride (based on the amount of chlorine shown by 

analysis) for two and a half hours at 180-200°; after which no further 

action was observed. The appearance of the product was the same as 

in previous experiments. The liquid product Avas distilled off and fractioned. It was found to consist of an excess of phosphorus oxychloride, 

of silicon tetraclilori.de, which was recognized through conversion into 

.the ether, and ethyl chloride. The liquid boiled entirely below 112°, 

and therefore none of the expected silicon oxychloride was formed. The 

solid product was markedly different from those before obtained. It
54 LABORATORY REPORT, 1890-'91. [»uu.oa

was only partly soluble in alcohol, and on boiling out with the solvent 

a large residue of silica was left. Besides a soluble silico-phosphoryl 

chloride and ethyl chloride the only products were silicon tetrachloride 

and silica. If the oxychloride be formed at all, it is at once decomposed 

in the presence of phophorus oxychloride 

Whether this actually occurs is questionable, as the oxychloride and 

all the other substances concerned are, by themselves, stable at a much 

higher temperature than that employed. I am unable to give any satisfactory explanation of the reaction.

Amorphous silica, prepared from water-glass and dried at 100°, gives 

with phosphorus oxychloride a small amount of silico-phosphoryl chloride, soluble in alcohol : 3-5 per cent of the silica was converted into 

this compound.

The silicon tetrachloride used as the starting-material of these experiments was made by the admirable method of Gattermann. 1 For preparing the silicon mixture I used, instead of test tubes, sheet-iron crucibles of about 200CO capacity. These are nearly filled with an .intimate mixture of three parts quartz powder and one part magnesium 

powder, tightly pressed down. On heating over a blast lamp, the reaction starts in a few seconds, and is indicated by the whole crucible suddenly becoming red-hot. During the reaction the hd must be held 

down firmly. I prefer to extract the magnesia from this product before 

using it, as less care has to be used in regard to temperature when 

passing chlorine over it. By using ice alone, to condense the chloride, 

nearly the theoretical yield is obtained; the crude product loses about 

15 per cent in the process of purification.

The orthochlorhydrines were prepared essentially according to the 

method of Friedel and Crafts.2 Any mixture may be used which coincides in composition with that of the chlorhydrine desired. The yield 

is never theoretical, no matter how long the heating maybe continued. 

The yields of pure substance, obtained after six distillations, were as 

follows: Monochlorhydriue, 65 per cent; dichlorhydrine, 40 per cent; 

trichlorhydrine, 47 per cent. More can, of course, be obtained by 

uniting and heating the residues.

Friedel and Crafts3 obtained the disilicic ether by adding to silicon 

tetrachloride, drop by drop, alcohol containing the calculated amount 

of water. They claim that the yield is nearly theoretical. I am not 

able to confirm this statement. By following their directions exactly, 

I obtained a mixture of ortho- and disilicic ethers, with ethers of much 

higher boiling points. After repeated fraction ing, only 33 per cent of 

the theoretical yield of disilicic ether was obtained, and the amount of

1 Ber. <1. deutsfili. chem. Ges. vol. 22, pp. 1H6-188.

2 Loo. cit,

3 Ann. eliiru. phys. [4] vol. 9, p. 26. -
STOKES.] CHLORIDES OF SILICOPHOSPHORIC ACID. * 55

ortho-ether Avas much greater. This is due to the fact that the added 

Avater acts on the disilicic ether already formed, giving more complex 

bodies, so that there is an excess of tetrachlori.de, which is converted 

into ortho-ether.

The essential results of these experiments may be summed up as 

folloAVS:

Phosphorus oxychloride acts on orthosilicic ether and its chlorine 

derivatives according to the following equations:

I. 4Si(OC2H5 ) 4 + SP0013=4SiP2 0PCl2 + 16C2H801. 

JI. 4SiCl(OC2H5 ) 3 + 6POCl3 =SiCl4 + 3SiP3OcCl2 +12C2H5C1.

III. 4Si012 (OC2H5 ) 2 + 4POCl3 =2SiCl4 + 2SiP2O6Cl 2 + 8C2H5C1.

IV. 4Si013 (OC2H5 )+2POCl3 =3Si014 + SiP2O6Cl2 +4CZH5CL

The body SiP2O6Cl2 is the chloride of a silico-pyrophosphoric acid, is 

decomposed by water into silica and pyrophosphoric acid and is easily 

converted by phosphorus pentachloride into silicon tetrachloride and 

phosphorus oxychlorfde.

The ether of disilicic acid acts similarly, giving a silico-phosphoryl 

chloride of different composition but analogous properties.

The chlorhydrines of disilicic acid, do not give \vith phosphorus 

oxychloride, as might be inferred, a silico-phosphoryl chloride and silicon oxychloride, but a mixture of the first with free silica and silicon 

tetrachloride.

Phosphorus trichloride also acts on orthosilicic ether at 200°j giving 

a white solid, and liquid products, Avhich Avill be further studied.
ON THE COLLOIDAL SULPHIDES OF GOLD.

BY E. A. SCHNEIDER.

The credit of having definitely established the proportions in which 

gold and sulphur combine is due to L. Hoffinann and G. Kru'ss. 1 They 

found, as a result of many elaborate experiments, that gold can form 

with sulphur only aurous sulphide Au2S and auroauric sulphide Au2S2, 

but not auric sulphide Au2S3 . It must be observed, however, that 

lately Antony and Lucchesi 2 have stated that they succeeded in preparing auric sulphide by-passing dry hydrogen sulphide over lithium 

aurochloride.

While studying both the. sulphides, which were prepared in a pure 

state by Kriiss, I repeatedly noticed their tendency to form colloidal, 

solutions. I have found in chemical literature some suggestions bearing on this behavior, but no special investigation upon the subject has 

been recorded. Consequently it seemed desirable to look into the 

matter.

COLLOIDAL AUROUS SULPHIDE.

Hofftnjftm and Kriiss state that freshly precipitated aurous sulphide 

forms with water a clear brown solution, without, however, laying any 

stress on its colloidal nature. * Although some of the properties of the 

solution mentioned by Hoffmann and Kriiss, for instance, coagulation by 

hydrochloric acid and by neutral salts (sodium chloride, potassium chlo- 

' ride), indicate clearly its colloidal character. I have, nevertheless, made 

an experiment to prove it directly. The brown, clear solution was placed 

in a dialyser and after the lapse of several days the liquid in the outer 

jar did not contain a trace of any gold compound. Consequently the 

aurous sulphide solution is colloidal, and to compare it with sodium 

sulphide, as Hoffmann and Kriiss have done, in order to characterize 

the position of gold in the periodic system, is not admissible, particularly as it is well known that the sulphides of the heavy metals in general can form colloidal solutions. This subject Spring and Boeck 3 and 

later Winssinger 4 have investigated. In order to prepare colloidal 

aurous sulphide in sufficient quantity the directions of Hoffmann and 

Kriiss should mainly be followed, but with the following changes:

1 Ber. d. deutsclien cbem. Gesell., vol. 20, pp. 2369 and 2704.

2 Gazzetta chimica italiana, vol. 20, pp. 601-607.

3 Bull, de la soci6t6 cliimique, vol. 48, p. 165.

4 Ibid., vol. 49, p. 452. 

56
SOHKEIDKB.] COLLOIDAL SULPHIDES OF GOLD. 57

Aurous cyauide isolated from potassium aurocyauide by means of 

hydrochloric acid is dissolved in the least possible quantity of potassium 

cyanide; the solution is then saturated with, sulphuretted hydrogen. 

Hydrochloric acid is now added and the liquid gently warmed until it 

becomes distinctly brown and cloudy, but the heating should be discontinued as soon as a heavy precipitate begins to form. This solution 

is next subjected to a prolonged' dialysis. In the dialyser remains a 

dark brown colloidal solution of aurous sulphide, which can be separated by decantation and nitration from solid aurous sulphide, which 

latter is usually present in considerable quantities.

The strongest solution obtained by this method contained 1-740 

grammes aurous sulphide in the liter. An attempt was made to concentrate this liquid in vacuo to half Sf its bulk. A small quantity, 

however, of aurous sulphide separated out when this degree of concentration was reached.

When a solution of aurous sulphide is heated to a temperature of 

200-230° gold separates out and simultaneously sulphuric acid is 

formed. On freezing and subsequent thawing aurous sulphide is 

deposited in solid form. The same behavior has been observed in the 

case of many other colloidal solutions. 1 It appeared to be of some 

interest to ascertain whether colloidal aurous sulphide possesses the 

property to undergo mutual decompositions similar to those of sulphuretted hydrogen and of the soluble sulphides of the alkalies and 

alkaline earth metals j and particularly whether it would react with 

other colloidal solutions, such as colloidal ferric hydrate, according to 

the following equations :

2Fe(OH)3 + 3 Au2S = Fe2S3 + 3Au2O * + 3H2O 

2Fe(OH)3 + 3Au2S = 2FeS + S + 3 Au2O + 3H2O

Some time ago Wright 2 studied the action of sulphuretted hydrogen 

on ordinary ferric hydrate. I find that colloidal ferric hydrate behaves 

in the same way. If sulphuretted hydrogen is conducted into a solution of colloidal ferric hydrate at ordinary temperatures iron sulphide 

immediately separates out. The reaction proceeds probably according 

to the equations 

2Fe(OH)3 + 3H2S = Fe2S3 + 6H2O 

2Fe(OH)3 + 3H2S = 2FeS + S + 6H2O

which Wright has demonstrated to be probable in the case of the ordinary compound. If solutions of colloidal ferric hydrate and colloidal 

aurous sulphide are mixed no reaction takes place either at ordinary 

or at higher temperatures. This fact confirms the hypothesis 3 that in

1 Zeitsclirift f. pbys. Chem., vol. 4, p. 486.

* Jour. Chem. Soc., 1883, vol. 43, p. 156.

3 C. Barus and E. A. Sehuoider: On tlio nature of colloidal solutions. Zoitschril't f. pliya. Choni., 

vol. 8, p. 278.

* The soluble aurous oxide has been described by Kriiss; Ann. Chem. Pharm., vol. 237, p. 2%.
58 LABORATORY REPORT, 1890-'91. [mjix.00.

colloidal solutions extremely small solid particles are held in suspension, for s'olid substances do not react among themselves, excepting 

possibly when very high pressure is used.

COLLOIDAL AUROAURIC SULPHIDE.

Weak solutions of colloidal auroauric sulphide have been already prepared by Winssinger. 1 Comparatively concentrated solutions of auroauric sulphide may be obtained easily and in large quantity when the 

freshly precipitated compound is boiled Avith potassium cyanide or potassium polysulphide until about half of the gold salt has gone into solution. The undissolved sulphide is rinsed now with water in a dialyser 

and subjected to dialysis. Af^r removal of all the crystalloids there 

remains in the dialyser a dark brown liquid, together with some solid 

auroauric sulphide, which can be easily separated by decantation and 

filtration.

The yield is equally good whether potassium cyanide- or potassiumpolysulphide is used. In the second case, however, it seems to be 

more difficult to remove the crystalloids, even by protracted dialysis.

The colloidal auroauric sulphide solutions are perfectly transparent 

to both transmitted and reflected light (the latter is not always the case 

with colloidal solutions).

When the solution is fro/en it behaves like the solution of aurous 

sulphide and most of the other colloids. It undergoes no change when 

heated to 240° in a sealed tube.

The strongest solution which I was able to obtain, according to the 

above described method, contained 0-8 gramme auroauric ^sulphide in 

the liter. Its color is dark brown and a layer of about 2 centimeters 

thickness is almost opaque. ,

In order to ascertain whether the auroauric sulphide had undergone 

change on dissolving, a liquid containing the compound in colloidal condition was coagulated.

The precipitated sulphide was reddish brown when moist; black 

when dried. The analysis gave data which corresponded well with the 

formula Au2S2 .

Colloidal solutions of aurous sulphide can be obtained by treating 

aurous sulphide with potassium polysulphide, but the yield is much 

smaller than in the case of auroauric sulphide.

That colloidal solutions are formed by prolonged washing with water 

of a precipitate which has been already acted on by a solvent has been 

observed several times. Wright 2 states that ferrous sulphide changes 

to the colloidal condition if washed with water after previously having 

been boiled with enough potassium cyanide to eifect partial solution. 

I have repeated the experiment and can fully confirm this statement.

'Bull, rte la soci6t6 cluniique, vol. 49, p. 452. 

* Jonr. Chern. Soc., 1883, vol. 43, p. 163.
SGHNEIDERO COLLOIDAL SULPHIDES OF GOLD. 59

Without knowing- of Wright's experiments I found several years ago 

that ordinary ferric hydrate may be converted into its colloidal form by 

a similar process. 1

Freshly precipitated ferric hydrate is easily dissolved by a neutral 

solution of aluminum chloride. Now, if an excess of ferric hydrate is 

present which does not further dissolve, and if the same is placed on a 

filter and washed with water until all salts present are removed it goes 

into a solution which seems to be in its properties almost identical with 

ordinary dialysed ferric hydrate.

The following explanation can be given of this behavior: If a solvent 

acts on a finely divided precipitate, single molecules throughout the 

whole mass of the latter go into solution. Thus the large aggregates 

of molecules are broken up into smaller ones. These aggregates of 

molecules may become, under certain conditions, so small that they 

remain permanently suspended in the liquid and form a so-called "colloidal " solution. It must be added, however, that this happens only in 

certain cases and with certain substances. If, for instance, silver 

sulphide is treated exactly in the same way as ferrous sulphide or auroauric sulphide with potassium cyanide and then washed with water no 

trace of a colloidal solution is formed.

An unsuccessful experiment, which was made with the intention of 

obtaining colloidal auroauric sulphide by another method, may be mentioned, as it gave rise to an interesting observation. If sulphureted 

hydrogen is conducted at ordinary temperatures into a solution of auric 

chloride, very little precipitate is formed as long as uudecomppsed 

chloride is present; the color of the solution becomes at the same time 

dark brown; thin layers of the liquid remain still transparent. This 

behavior seemed to indicate that at first only colloidal auroauric sulphide is formed. In order to confirm thie assumption by experiment a 

solution of auric chloride was incompletely precipitated by sulphureted 

hydrogen and then placed in a dialyser. After the lapse of a fe\\r hours 

the unchanged chloride of gold was diifused; in the dialyser, however, 

remained finely divided gold instead of colloidal auroauric sulphide as 

had been expected.

It appears that the gold chloride had acted on the auroauric sulphide 

according to the following equation:

Au2S2 + (Au013 )4 + 8H2O = Au6 + 2H2SO, + 12HC1.

And, indeed, if a mixture of the solutions of colloidal auroa,uric sulphide and gold chloride is gently heated gold immediately separates 

out. The following quantitative experiment definitely confirms this 

view. 14140 grammes auroauric sulphide (one molecule Au2S2 ) were 

heated on the water bath with four molecules auric chloride, corresponding to 2-8280 grammes gold. After the lapse of four hours the 

liquid had become entirely colorless and the brownish black color pf

Ann. Cbem. Pharin., vol. 257, p. 374.
60 LABORATORY REPORT, 1890-J91. [HULL. 90.

auroauric sulphide had changed entirely to the yellowish brown of 

metallic finely divided gold. The gold which had thus separated out 

was carefully washed, dried, digested with carbon bisulphide for some 

time and ultimately dried at a temperature of 110°. Its weight after 

this treatment amounted to 4-2708 grammes on heating and calcining 

the same a sulphur flame was noted, and a loss of 0-0327 grammes 

or 0-77 per cent was found; consequently found 4-2381 grammes gold, 

instead of 4-2420 grammes.

The presence of sulphuric acid as required by the above equation was 

only qualitatively proved. The presence of a small quantity of sulphur 

in the gold can be explained by the fact that the auroauric sulphide 

used was not freed originally from the sulphur which is always formed 

when gold chloride solution is precipitated by sulphureted hydrogen. 

Consequently it was possible for the metal to be contaminated with 

traces of sulphur, which are removed only with great difficulty by carbon bisulphide.

By a second, but not strictly quantitative experiment it was shown 

that gold chloride reacts with auroauric sulphide in the above described 

manner even at ordinary temperatures, but the reaction proceeds more 

slowly. The reduction of boiling solutions of auric chloride by sulphureted hydrogen, which has been already observed by Level, 1 can be 

explained by the .above reaction.

Finally, colloidal auroauric sulphide was prepared by prolonged 

treatment of freshly precipitated auroauric sulphide with sulphureted 

hydrogen water. Freshly precipitated auroauric sulphide was suspended in a few hundred cubic centimeters of water and placed in a 

dialyser. Sulphureted hydrogen was conducted into the latter for a 

week, and the water in the outer jar was frequently renewed. After 

the lapse of this time a light brownish yellow solution had formed in 

the dialyser. This solution contained 0-023 gramme auroauric sulphide 

per liter.

It is evident that more concentrated solutions could be obtained if 

the treatment with sulphureted hydrogen were continued for a longer 

period. If, however, we compare this method with the preceding it 

appears long and tedious. Some of the facts mentioned may possibly 

throw light on certain chemico-geological problems.

It appears probable 

(1) That the separation of free gold in the upper strata of the earth's 

crust may have been effected by the action of sulphureted hydrogen 

on chloride of gold ;2 for the constant associate of gold, pyrites, owes 

its formation, as Doelter 3 has shown in his investigation on that subject, to the action of sulphureted hydrogen water on the various oxides 

of iron at temperatures below 100°.

' Annal. Chim. Phys. (3), vol. 30, p. 356.

2 Tlio original formation of gold chloride in the earth-crust can bo explained hy.tho action of chlorine 

on gold at a considerable depth.

3 Zeitschrift f. Kryst. nnd Win., vol. 11, p. 30.
COLLOIDAL SULPHIDES OF GOLD. , 61

(2) That the formation of gold could have taken place at no very 

great depth, for we have seen that already at much lower temperatures 

auric chloride effects the separation of gold from auroauric sulphide 

solutions.

(3) That the formation of pyrites has taken place in strata nearer 

the surface than those in which"the formation of gold took place, for it 

is necessary to assume that the mineral acids which are formed, when 

gold is separated out by sulphureted hydrogen from gold chloride 

solution, had to be first neutralized by the bases of strata of considerable thickness in order to make possible the formation of pyrites by 

the action of sulphureted hydrogen on ferric oxide.

In connection Avith this investigation I have tried the action of high 

pressures on some colloidal solutions.

A colloidal solution of ferric hydrate (0-64 per cent F2O3 ) was sub. 

jected at temperatures of 17° and of 100° to a pressure of 1,700 atmospheres. No visible action was observed. A colloidal solution of silicic 

acid (1-22 per cent) also remained at 17° and at 100° under the same 

pressure entirely unchanged.
MISCELLANEOUS ANALYSES.

THREE MINERALS FROM COLORADO. 

[Collected by Whitman Cross, analyzed by L. G-. Ealdns.] 

A. Heulandite, from Anthracite creek, Gunnison county. 

B. Diaspore, from Mount Bobinson, Ouster county. 

0.. Alunite, from Knickerbocker Mil, Ouster county.

Si02 . .......................

Ala03 .. .....................

Fe»0,.. .....................

PnH

MgO.......... ..............

K2O..... ....................

TSs^O .......................

H,0....... ..................

S03 .........................

Sp.gr................'.......

Heulandite.

57-38

17.10

8-07

 82

10002 

2'24 21°

Diasporo.

81*97

99-40

Alunite.

2-82

 35

i Q-m

35-91

99-37

YELLOW SMITHSONITE FROM ARKANSAS.

[Collected in Marion county by W. P. Jenney, and analyzed by H. N. Stokes.]

Briglit golden yellow in color. Takes a fine polish. Known loc'ally 

as "turkey-fat ore."

SiOt... ....................... f ....... ..................... -06

CO^ ....................................................... 34-68

Cu ........................................................ tr.ice

CdS ....................................................... -25

CdO ....................................................... -63

ZnO ........................:.............................. 64-12

FeO....................................................... -14 .

CaO................................... ".................... -38

100-26
CLAHKE. ] MISCELLANEOUS ANALYSES. 63

ROCKS AND CLAYS FROM THE ZINC REGION OF MISSOURI AND KANSAS,

[Collected by W. P. Jeiinoy.)

First. Two dolomites from the Oswego laud, Joplin, Missouri.

[Analyzed by L. G. Eakins.]

CaO......... ..........................

MgQ. .......... .......................

AlA,*V>j- .........................

A.

14-79

1-32

90-77

100-47

K.

__ 

00.70

1-03

41-55

100-22

Second. Seven cherts.

A. Partly altered, from East Hollow, Belleville, Jasper county, 

Missouri.

B. Altered to " cotton rock," same locality. 

0. Unaltered, same locality. 

D. Surprise mine, Joplin, Missouri. 

B, F. Bonanza shaft, Galena, Kansas. 

G. Altered, same locality.

[Analyzed by K. A. Sulmculor.j

SiO.,. ....... ..............

AU>3 , FeA. ............. 

CaO.......................

My;O. .....................

Jgn.. .....................

SiO........................

Al-A.lVOj....... ........

CaO .......................

M"-O

Ign...... ..................

A.

98-1)2

 48

.02

99-87

Ji.

98-71

.4;i

 r>o

99-09

E.

99-23

 22

 02

r)0

99-97

C.

98-17

 83

 78

99-84

F.

98-60

00

4)9-02

D.

 29 

 04

]()0-13

G.

99-13

 16

.01

 20

99.50
64 LABORATORY REPORT, 1890-'91. [BULL. 90.

Third. «Jasperite" and "tripoli."

A. Jasperite, from Joplin, Missouri.

B. Jasperite, from Galena, Kansas.

C, D. Tripoli, from Seneca, Newton county, Missouri.

[Analyses by L. G. Eakins.]

SiOz. ......... ............

ALA, FejOs..-.--. .--...-

CaO. ......................

MgO......................

HjO...... ................

A.

95.77

1-84

 54

 24

1-17

99-56

B.

97-33

1-89

 11

 09

 77

100-19

C.

9S.29

 62

 09

Ml

100-11

D.

98-93

 63

.04

 68

100-28

Fourth. Eleven "tallow clays." 

A, B, C, D. From Joplin, Missouri. 

E. From Aurora, Missouri.

[Analyzed by T. M. Chatard.]

Ign. ..............

Soluble ALjOa- ....

Soluble Fo/)3 -....

Soluble ZuO ......

Soluble CaO ......

Soluble MgO .....

A.

17-10

40-64

5-72

1-30

32-46

1-80

.27

99-38

B.

16-74

43-07

7-60

1-12

29-43

1.70

 32

99-98

C.

17-63

6-17

1-16

34-28

2.13

 27

100-98

D.

16-95

6-45

1-53

33-55

1.77

 30

100-17

E.

16'90

10-01

3-62

33-49

2-09

 25

100.46

F. Gave Springs miue, Jasper county, Missouri. 

G. Coon hollow, Boone county, Arkansas. 

H. Great Western mine, Granby, Missouri. 

I, J, K. Woodcock mine, Granby.

[Analyses by II. N. Stokes.]

Soluble A1S 03 .........

Soluble ZnO.... ......

Soluble CaO..........

Soluble MgO.........

F.

10-37

51-64

7-38

10-34

14-35

1-55

 35

95-98

G.

8-36

47-20

6-34

4-40

30-50

1-91

 75

99-46

II.

8-22

44-14

10-78

3-89

29-54

2-65

:90

100-12

I.

7-99

8-21

2-75

38-59

2-77

 78,

100-21

J.

9-19

44'79

8-93

5-98

26-23

2-01

 46

97-59

1C.

7-52

6-46

3-49

38-90

2-56

 42

100-28

Iii these analyses the terms insoluble and soluble refer to solubility 

pf the material in aqueous hydrochloric acid, ------ <
CLARKE. ] MISCELLANEOUS ANALYSES. 65

TWO FELDSPARS.

[Separated from the cheolito-syenite of Litchflcld, Maine, by W. S. Bay ley; analyzed by W. H. Melville..!

H2O ........................

Si02 ........................

A1«0S ...... .................

FeO ........................

CaO ........................

MgO........................

K2 0 ........................

Na.,0 .......................

Sp.gr., 2-50.

 17

 9^

 33

 16

14-14

1-68

100-06

Sp. fir., 

2-622.

 09

IIQ.OQ

19-02

.OO

 31

 09

 39

10-81

99-82

SIX SANDSTONES.

A, B, 0. " Peebles-Henley stone," from Portsmouth, Ohio.

[Analyzed by H. N. Stokes. Alkalies probably present, but not sought for.]

Si02 ........................

A12 03 .......................

Fe203 ---- ..................

FeO ........................

MgO........................

A5-15.

 65

 27

 28

 99

97-74 

98-00

B.

89-32

5-52

 87

.yc

 51

1-49

98-06 

96 '90

C.

87-12

5-96

 85.

 85

 73

9'ftn

97-51

os.rn

J). Brown sandstone, Humnielstown, Pennsylvania. 

E. Potsdam sandstone, Sank county, Wisconsin. 

F. Banded sandstone, Peoa, Utah.

[Analyses by E. A. Schneider.]

SiOa ........................

Al<03 ...... .................

Fo^Oj...- ...................

FeO ........................

CaO ........................

MgO........................

KS0 ........................

NsiiO .......................

H.,0 ........................

D.

5-81

1-77

 31

 20

 53

 06

 49

99-93

E.

! «

 18

99-91

F.

2-02

'04

 08

 40

99-14

Bull. 90-
66 LABORATORY REPORT. 1890-791. [BULL. yo.

SEVEN MARBLES AND DOLOMITES.

A and B. From Happy valley, Georgia. 

C. From Kutland, Vermont.

[Analyses by L. G. Eakins.J

CaO ........................

MgO........................

AW), . ...................

FeO ........................

C02 . ............. ..........

H20 ........................

A.

53-91

 83

 17

 05

43-16

 13

1'84

100' 09

B.

53-09

 si

 15

 06

43-13

 17

2-01

100-04

C.

CA-7O

 39

 14

39-80

1-01

8-00

100-13

Analyses of portion innoluble in hydrochloric acid.

Si02 . .......................

A.l203 . ......................

FeO ........................

MgO....- ...................

A.

58-21

7-37

 31

12-53

20-42

98-84

B.

15-58

14-52

12-88

98-46

C.

56-69

31-16

2-13

2-68

3-27

95-93

D. Marble from Lee, Massachusetts.

E. Compact gray limestone, from Greason, Pennsylvania.

F. Dolomite, from Cockeysville, Maryland.

G. Crystalline limestone, Eureka, Nevada,

[Analyses by E. A. Schneidor.]

CaO .................:....-.

MgO........................

ALA, Fo203 ................

C02 . ............... .....

H20,105° ...................

D.

30-88

21-42

 24

46-72

 19

99-45

E.

39-26

9-00

38-82

 18

11-07

 75

99-08

3T.

29-08

20-30

 40

44-26

5-57

99-61

G.

30-60

21-69

47-13

 53

99-95

NINE BOCKS FROM MARYLAND. 

[Collected by G. H. Williams; analyzed by W. F. Hillcbrand.]

A. Granite, from Gnilford. 

B. Granitite, Sykesville.
CLAKKE. ] MISCELLANEOUS ANALYSES. 67

0. Hornstoue, from, contact with limestone, Sykesville. 

D. Dissolved inclusion, Sykesville.

SiOa ................*.......

AlgOj. ......................

~\?t\ f~\

PcO ........................

CftO. .......................

MgO.........................

K.,,0 ........................

NajO. ......................

H20 ........................

'

A.

72-57

15-11

1-65

 30

4-33

3'92

 47

99-96

K

71-45

14-36

2-78

1-58

1-17

3-28

1-30

99-94

C.

Tl-77

1-02

11-09

 65

 09

 66

1-16

100-10

D.

47-35

3-] 5

2-20

1-60

0-83

2-84

3-15

99.82

E, F, G. G-ranitites.

H, I. Gneisses.

E. From Woodstock, the remainder from Dorsey's run.

Si02 ..............

A1203 ...... .......

Fo203 ....... ......

FeO........ ......

CaO..............

MgO..............

K20. .............

If a,0. ............

H.,0....... .......

E.

71-79

' 15-00

 77

 1-12

2-50

 51

4-75

3-09

 04

100-17

F.

62-91. 

19-13

 98 

3-20 

4'28 

1-69 

3-38 

3-94

 63

100-14

Manganese and traces of lithia present in all. SrO and BaO not 

looked for. TiO3 and P2O5 , if present, are included with the alumina.

ERUPTIVE BOOK FROM KENTUCKY.

From a dike in Crittenden county.

[Analyzed by W. F. Hillobrand. Material dried at 100°.]

G.

70-45

15-98

 75

1-84

2-60

 77

3'59

3-83

 45

100-26

H.

07-33

15-31

3-39

8-19

3-95

4-30

4'57

1-22

1-80

100-12

I.

48-92

16-57

4-21

9-18

9-69

5-98

1-56

2-47

1-68

100-26

SiO. 

TiO.,

Cr.2 0:!

33 -84 

3-78 

5-88

-18 

7-04 

5-16

-16

-10

FeO .....................................................

MnO ................................ .....................

NiO......................................................

CoO ....................................................... trace

CaO ....................................................... 9-M

BaO ....................................................... -06

MgO. ...................................................... 22-90

K2 0 ....................................................... 2-04
68 LABORATORY REPORT, 18!30-'91. [BULL. 90.

Na2O ............................

H2 0 .............................

P.O.. ............................

Cl...... ........................

CO...............................

.......................... -33

.......................... 7-50

.......................... -8!)

.......................... -05

.......................... -43

99-86

FOUR GRANITES FROM MISSOURI.

From NE. £ Sec. 6, T. 33, E. 5 E.

[Analyses by W. H. Melville.]

Si02 . ...............

Ti02 . ...............

p»o« - . .......

A1203 ---. ---.. -----

Fe203 .. .............

FeO. ...............

KiO.. ..............

MuO...... ..........

CaO.. ..............

MgO................

K20...... ..........

A.

60-94

 25

 13

15-19

1-88

 CO

 03

1-15

 92

3-95

 4'29

 14

 85

99-32

B.

72-35

 44

 J3

1.3-78

1-87

 30

 20

 06

 87

 42

4-14

4-49

 22

99-87

0.

71-33

 55

 16

12-55

3-75

 85

 15

 04

 94

 58

4-52

4-20

 32

 30

100-04

D.

71-88

 22

 15

12-88

3-05

1-05

 02

1-13

 33

' 4-21

4:4(5

 17

 26

99-81

THREE ROCKS FROM MINNESOTA.

A. Hypersthene gabbro from SE J Sec. 20, T. 65 N., E. 4 W.

B. Olivine gabbro, SE. J Sec. 19, T. 63, E. 9 W.

0, Oliviue gabbro, S. quarter post, Sec. 35, T. 61 N., E. 12 W.

[Anaylses by H. N. Stokes.]

SiOj.... ....................

Ti02 ........................

T> C\ '

Al^..,....... .............

yo20s . ......................

Crt03 .. .....................

FeO...... ............ ......

NiO............. ............

MnO-. ............. ........

CaO........................

MgO........................

TC20. ........................

NajjO.. .....................

H20, 105°............ .......

HjO, above 105° .............

A.

46-96

 62

 03

14-13

 76

 06

 93

9-32

15-97

 35

 07

]-2G

100-09

B.

45-66

 92

 05

16-44

 66

 16

7-23

Jl-57

 41

 07

 83

100-03

0.

1.19

 02

21-30

 81

Q'17

 04

9-83

7-90

 34

 14

1-02

100-75
CLARKE. ] MISCELLANEOUS ANALYSES. 

ROOKS FROM COLORADO.

69

A, B, C. Three rocks from Gnnnison county; A, Mount Marcellina; 

B, Storm ridge; C, Mount Carbon.

[Analyse* A anil C by T. M. Chatard; B by L. O. Eakins.]

SiO,. .......................

TiO.,. .......................

P,0«. .......................

A18 0S . ............ .....:...

Fe2O3 ... ....................

FeO. ........ ...............

MuO. .......................

BaO ........................

CaO ........................

M<?0. .......................

K2O ........................

Na20 .......................

H2 0. 105°...................

A.

62-85

 41

 48

10-21

3-08

1-46

 15

 11

4-72

1-47

3-10

3-49

 29

2-03

1)9-85

R

C1.-42

 117

 14

]7'C9

4-24

1-74

 19

 09

5-29

1-91

8-19

} '97

100-28

C.

05.36

 52

 25

15-48

3-09

1-21

 19

 08

i.r,1)

3-41

o.r.o

c -82

( -70

100-36

D. Ehyolite from Mount Eobinson, Ouster county.

[Analysis by L. G. EaTdns. ContaiiiH much diaapore.

SiOj.......... ........

Als03 -----. --...-...-.

CaO..................

MgO. ................

Na»0. ................

H2 0. .................

D.

69-67

 07

 34

4'73

9-27

100-24

E, F, G, H, I. Spherulites from Ouster county; E, G, TT, from 

Rosita; F, T, from Silver cliff.

 [Analyses by L. G. Eakins.]

Si02 ..............

ALA.............

CaO..............

MtfO. .............

K.2O. ......... ....

NiteO .............

HjO ..............

"F*

74-47

13-87

7-40

9. in

1-88

100-29

F.

9-54

 19

5-00

 62

-60

100-01

Gr.

80-61

10-94

*2(J

 09

3-02

2'90

9-90

100-02

][.

79 ll'l

'43

 11

5' 26

2

,ro

.(\ft

100-49

I.

7Q-77

"34

 09

0.19

 70

100-32
70 LABORATORY REPORT, 1890-'91. [BUM,. 00.

ROCKS FROM MONTANA.

Eeceived from G. P. Merrill. A, from lills northwest of Bed Bluff; 

B", between Antelope and South Bowlder creeks; 0, hills east of South 

Bowlder creek; D, near North Meadow creek; E, near North Meadow 

creek; F, northwest of Bed Bluff.

[Analyzed by L. O. Eakins.]

SiO., ..............

TiOs ....... .......

A1203 ....... ......

Cr2 03 .............

Fe203 ....... ......

FeO...... ........

MnO.. ............

NiO ..............

CaO ..............

MgO..............

BaO ..............

KS0 ..............

NajO .............

H*0.. ............

P»0S . .............

S. ................

' A.

48-95

 81

5-69

 05

1-20

12-11

 08

 1C

. f( -33

23-49

 79

1-58

 18

 12

100-54

Ji.

50-82

 59

11-44

 03

 25

8.94

 ]9

8-14

14-01

 06

3-45

1-79

 58

 20

100-49

0.

50-03

 61

14-08

2-92

6-11

.08

7-46

10-73

. .04

2-64

1-46

3-70

 42

100-28

IX

46-13

 73

4-69

 04

.73

16-87

 no

4-41

25-17

 08

1-38

 07

 24

100-63

F

'51-83

 29

7-98

.31

1-48

8-28

 11

5-20

24-10

 06

 35

 29

 09

100-43

F.

59-48

.93

16-37

.03

3-21

3-17

 19

4-88

3-29

 13

2-81

3.30

2-01

 41

100-21

Eock and separations from top of Square butte, Bear Paw mountains.

[Analyses by W. H. Melville.]

SiO..........................

TiOj.-.-.- ..................

T> A

ci............. ..............

A1203 - ......................

l^O3 ....... ................

TVO

NiO. ........................

MuO...... ..................

CaO.........................

MgO........................

SaaO...... ..................

KgO.................. .......

HjO, 100° ...................

H20, above 1000.. ...........

LossO Cl. .............-.".

Rock.

 29

 13

 43

20-08

1-31

4-39

 09

2-14

 63

5-61

7-13

 26

1-51

- 100.45 

 10

Hornblende.

38-41

17-65

3-75

21-75

 15

10-52

2-54

2-95

1-95

 24

99-91

Sp. gr. 

2-265.

41-56

4-79

29-48

.49

 49

 15

19-21

 91

 45

3-73

101-26

Sp. gr.

2-255.

49-54

1-67

25-07

 40

 22

.20

'15-32

 89

93-31 

 38

92-93
MISCELLANEOUS ANALYSES. 71

Two rocks from the Crazy mountains: A, theralite, Gordon's Imfctej 

B, porphyritic theralite, Elbow creek.

[Analyzed by K. A. Schnoider.]

SiOa ..................... ..............

A1A .................................

Fe»0g. ................................

FeO........... ........................

CaO. ......... .........................

MgO. .................................

MnO... ...............................

KjO........ ...........................

Nn.,0.. ......... .......................

HsO, 105° .............................

A.

44-fl

17-20

4-64

3-73

10-40

G-57

3-04

4-45

 77

3-30

99-11

B.

47,- 67

18-22

3-85

8'03

6-35

 28

1'fi9

.00

2-97

100-15

Four rocks from the Crazy mountains: A, green dike parallel to 

theralite; B, divide between first and second large creeks west of 

Smith's; C, Peaked butte; D, green dike north of long theralite dike.

[Analyzed by W. IT. Melville.]

SiO,.. .......................

TiO». .......................

 p t~\

Ala03 . ......................

FeA .......................

FeO. ...... ..................

MnO........................

CaO.........................

MgO.......... ..............

 NtiyO.......... ..............

K2O.... .....................

A.

08-70

 10

19-20

3-37

 58

 10

1-41

 76

8-55

 07

2.57

100-00

B.

02-17

18-58

2-15

1-05

1-57

 73

7-5G

O.OQ

 07

99-50

0.

59-CG

 14

10-97

'( is

1-15

"19

2.32

 80

8-38

407

 07

O.KO

9!)' 50

D.

17-52

 35

 50

 34

7-30

4-28

.04

99-07
72 LABOEATOEY EEPOET, 1890-*91. 

ROCKS FROM ARIZONA.

A series of four from the Santa Maria basin.

[Analyzed by W. F. Hillebranrt.]

[Rtri.r,. J)0.

SiO, ........................

TiOg. .......................

A1A .......................

FeA----------------------

FeO. ......... ...............

MnO...... ..................

(NiCo)O ....................

CaO....... ..................

SrO. ........................

BaO-.... ...................

MgO...... ..................

K20.. .............. .........

Nn,20. .......................

T> ri

el.................. ........

1.

49-30

 98

JO-35

9-<W

8-55

 19

.05

 04

7'0fi

 82

 22

 65

 30

100-25

2.

55-35

.07

12-71

4-67

2-06

.08

 05

5'77

 19

6-29

4-8G

2-65

2-67

1-18

 58

99-98

;t.

' 57-04

 94

13-60

4-96

1-77

 07

6-23

 22

4-43

4-95

3-08

1-11

1-10

 63

100-36

\.

57-48

 94

14-09

^ 91

1.35

 09

 08

6-05

 23 : 3-49

4-09

3-00

1-20

1-37

 65

99-92

ROCK FROM EUREKA, NEVADA.

An andesitic pearlite.

[Analysis by "W. H. Melville.]

Si02 ...... ........................

 i0.2 .. .. ...............

Ko5 . ..........

A12 03 . ............................

Fe.2 03 . ............................

FeO ..............................

NiO ..............................

MnG .............................

CaO..............................

MgO. .............................

K2 o ............................:.

Na2 0 ..................... .......

H20, 105°. ........................

H20, above 105° ..................

........................ 65-13

........................ 58

........................ -23

........................ 15-73

........................ 2-24

........................ 1-86

........................ -07

........................ trace

........................ 3-62

.............:.......... 1-49

........................ 3-96

........................ 2-93

........................ -52

........................ 1-91

100-27
CLARKE. ] MISCELLANEOUS ANALYSES. 

BOCKS FROM CALIFORNIA.

73

Three from Mount Diablo: A, diabase, somewhat altered; B, diabase, fresh; C, pyroxenite.

f Analyzed by W. IT.

SKV .......................

Ti02 . .......................

P-iOs... .....................

A1A-----------------------

Cr»0a .. .....................

Fe203 - ......................

FeO. ........... ............

NiO.. .......................

MnO. ...... .................

CaO............ ............

Na20...... ..................

K,0.. .......................

H20, 100° ...................

H2 0, above 100° ............

A.

51-58

3-05

14-99

2-04

8-30

8-59

0-51

3-08

 31

 34

2-C7

99-70

B.

52-00

 47

 13

14-34

2-11

7-74

8-05

9-20

1-74

 73

 59

2-90

100-12

0.

53-25

truce

2-80

 54

 09

5-93

 07

 09

1G'22

10-01

 19

 or>

 24

90-98

Four collected by H. W. Turner: A, Table mountain, basalt, Tuolumne county; B, basalt, Pluinas county; C, dolerite, Plumas county; 

D, quartz porphyrite, Plumas county.

[Analyzed by W. F. Hillcbrand.]

SiOj.. .......................

Tio........ .................:

Al./)3 .......................

Fe2 0:< - ......................

FeO.... ....................

MuO........................

CuO ........................

BaO. .......................

MgO.... ....................

KaO. ......... ..............

Na,2 0 .......................

H20, 100° ...................

H2 O, above 100° ..............

P206 . .......................

COj.- .......................

FeSs. .......................

A.

 r>6-i9

 69

10-70

I1-05

4-18

 10

c-5;i

 19

3-79

4-4C

2-53

 34

 06

 55

100-02

}',.

50-50

1-71

14 71

3-54

8-90

 13

7-58

 25

4-07

2-10

2'94

1-00

1-12

1-14

99-81

C.

53-9 1

r>'>

17-95

4-80

 10

10-40

5-52

1-34

2-90

 20

 20

 21

..........

100-31

D.

73-25

1-74

2-23

 28

3-79

2-09

 07

1-03

1.05

 58

99-90

Also ti-aocs of lithia and slrontia.
74 LABORATORY REPORT, 1890-91. 

SINTER FROM QUEENSLAND.

[BULL. 90.'

From the Mount. Morgan gold mine. Analyzed for comparison with 

the sinters from the Yellowstone National Park.

[Analysis by E. A. Schneicler.]

SiO,'........................................................ 94-02

AlgOs+FeaOs............................................... 2-27

CaO........................................................ -07

MgO ....................................................... trace

H2 0,105° ................................................... 1-07

HsO, ignition ............................................... 2-29

99-72 

TWO CLAYS FROM FLORIDA.

A, from Tampa5 B, from Lakeland.

[Analyses by L. G. Eakina.]

A. B.

Si02 ........................ 70-78 ' 80-39

11-33 i 15-03

CaO ........................! 2-18: 1-22

H2 0 ..............:.........{ 14-55 4-34

98-84 j 100-98

IRON ORES FROM WEST VIRGINIA.

[Analyses by H. ¥. Stokes.]

First, from Cherry run, near the Potomac river.

H8 0,105°................................................... -81

Fe.......................................................... 50-16

Mn ......................................................... '04

S........................................................... 06

P........................ .................................. 80

Insoluble.................................................... 14-43

Second, a series from Tazewell county.

j^

Moisture, 105° .............. l-(57 1-59 1-10 3-]7 1-24

Fo.......................... 30-81 56-48 54-01 50-07 40-75

Mn ......................... 5-42 -47 -26 traoo

S ........................... -09 -03 -09 '25 -08

P........................... -04 1-08 -95 -91 trace

Insoluble................... 26-19 1-85 4-2G 2-63 32-37
CLARKE.] MISCELLANEOUS ANALYSES.

COAL AND COKE PROM WEST VIRGINIA.

75

From the Thomas Vein, Davis. A, upper coal; B, middle coal; 0, 

lower coal; D, 48-hour coke; E, 72-hour coke.

[Analyses by L. G. Eiikiiis,]

Abb...... ..................

A.

65- CO

22-87

 64

10-89

100-00 

 64

 06

I*.

05-99

23-88

 68

9-45

100-00 

1-39

 02

0.

72-76

22-90

 96

3-38

100-00 

 59

 01

».

87-08

 95

 23

11-74

100-00 

 63

 oc

K.

» 90-05

1-10

 15

100-00 

 70

TWO COALS PROM UTAH.

A, Little Cottonwood gulch, near Salt Lake city; B, Wasatch 

mountains.

[Analyses by L. G. Eakina.]

Volatile hydrocarbons ......

Ash ........:...............

A.

85-83

7-15 

2-98

4-04

100-00

B.

42-81

24-60 

25-57

7-02

100-00

I N I) E X.

Page. 

Alunite .................................... 02

As trophy llite. .......... .................. 41-42

Aurous sulphide .............._......... 56-61

Biickstrom, cited.......................... 41

Biotite...................................11-12,13

Bismuthinite.............................. 40

Brogger, W. C., cited...................... 41,42

Calciummolybdate ......._............. 34-37

Chatard, T. M., analyses by............... 04,69

Chert....................................... 63

Clarke, F. W., on the constitution of certain micas, etc ...................... 11-21

Clay........................................ 64,74

Coal........................................ 75

Coke......_.. _.. . ..... ..._ . ,.. 75

Colloidal sulphide of gold ................ 56-61

Cooke, cited................................ 14

Cross, Whitman, quoted on thin sections

of tscheffkinite...................... 42-43

Delafontaine, cited........................ 29

Demarcay, cited..._...................... 29

Diaspore....... ........................... 02

Dolomite................................... 03,60

Eakins, L. G-.. analyses by................ 6.%

63,64,66,09,70,74,75

Engle, Horace M., acknowledgments to. 42 

Eruptive rocks........... ............... 07

Feldspar................................... 05

Gabbro.................................... 63

Gneiss ............ .......... .. .... 6<

Granite.................................... 66

Granitite................................... 60,07

Hallite...................................14,15,16

Heulandite ................................ 02

Hidden, W.E., aid by ........ ............ 22,23

Hillebrand, W. F., onuraninite.......... 22,25

on the isormorphlsm and composition of thorium and uranous sulphates.........-..-....--.------------ 26-31

analyses by...........................67,72,73

Hoffman, G. C., acknowledgments to.... 24

Hornstone................. ............. 67

Iron ore_................................. 74

Jasperite.................................. 64

Konig, cited............................_ 41

Lenni ....................................14,15,16

Page. 

Limestone.................................. 66

Liudgren, Waldemar, aid by............. 12,14

Losch, A., acknowledgments to .......... 24

Marble..................................... 66

Melville, W. H., on crystallography of

thorium and urauous sulphates. 31-33

on powellite-calcium molybdate... 34-37

analyses by.................65,68,70,71,72,73

Merrill, G. P., quoted..................... 19,20

Meteorites,analyses.._................ 45,40

Mica from Henderson county, N. C ....11,12,13

Micas, paper on constitution of.......... 11-21

Natrolite................................... 38

Nivenite................................... 22,23

Packard, R. L., acknowledgments to.... 31

Painterite ................................. 17-19

Powellite...... ............................ 31-37

Protovermiculite ..........._.........11-12.13

Rammelsburg,cited ...................... 29

Rhyolite................................... 69

Roozeboom, cited ......................... 29

Sandstone................................. 65

Schueider, E. A., on the constitution of

certain micas, etc ------------- 11-21

on the colloidal sulphides of gold.... 56,61

analyses by........................63,05,71,^4

Sinter..........0............................ 74

Smithsonite............................... 62

Spessartite garnet........................ 39

Spherulites................................ 69

Stokes, H. N., on the action of phosphorus 

oxychloride on the ethers and cnlorhydriues of silicic acid ........._. 47-55

" analyses by.......................62,64,68,74

Therolite.................................. 71

Thorium and uranous sulphates, paper

on isomorphism and composition of 26-33 

Tourmaline ............................... 39

Traube, H.citedby ....................... 37

Tripoli..................................... 61

Tscheffkinite.............................. 42

Tschermak, cited ......................... 16,17

Uranium sulphate, crystalline form of.. 32 

Uranium-thorium sulphate .............. 32

Uraninite.................................. 22-25

Vermiculite ............................... 11-21

77

O