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per Mountain Mine, near Morenci, Arizona, and from the American Eagle Mine, Copperopolis, Utah. In the first-mentioned locality, the substance forms incrustations of small, blue, fibrous tufts in a quartz gangue. Upon alteration it gives rise to a greenish-yellow, and finally to a fibrous yellowish-white material, often associated with hydrous aluminium sulphate. The Copperopolis specimens are velvety coatings of azure-blue silky fibers on a mixture of clay and lettsumite. The analyses of the two varieties, which are almost identical in composition, lead to the formula Cu,Al,(OH),,SO,+2H,O.

So, CuO A1,0, Fe,O, H2O Ins. 12.49 46.71 16.47 1.34 21.89 .44

Sp, Gr.

2.737

-Crystallized metacinnabarite (which has heretofore been found only in amorphous masses) has recently been discovered in the New Almaden Mine, California.14 The crystals are implanted on quartz containing cinnabar crystals, which in turn occurs incrusting a selvage of clayey material forming an ore seam, whose origin is referred to solfataric action on the country rock. Spheres of a black organic substance are imbedded in the metacinnabarite, whose density is 7.118. Its composition follows:

.90 .15 .71

Quartz Org. Matter

4-57

.63

S Hg Fe Co Zn Mn CaCO, 13.68 78.01 .61 tr. The crystals are rhombohedral and hemimorphic, with an acute pyramidal habit, and an axial ratio a:c=1:.2372. In rotted galena on a contact between limestone and mica-schist at Mountain View Lead Mine, near Union Bridge, Md., Williams 16 has found small but good crystals of anglesite and cerussite, and a single crystal of sulphur, all of which are products of the decomposition of the lead ore. The three principal types of the anglesite are prismatic, parallel to the brachyaxis, with P and P predodominating, cuboidal, with P and Pthe principal forms, and prismatic in the direction of the macro-axis, with P determining the habit. The cerussite presents a great variety of habits. One elbow twin is peculiar in that each of the two individuals is bounded on the inner side by P, while the outer side contains in addition the brachy-domes P, P, and 2P. The sulphur crystal is very small, but it contains thirteen forms, of which eight are in the zone of the ground-pyramid and one P is new. -The polycrase reported by Messrs. Hidden and Mackintosh 16 as oc14 Melville. Ib., Oct., 1890, p. 291.

15 Johns Hopkins Univ. Circ., No. 87.

16 Amer. Jour. Sci., June, 1890, p. 302.

1008

curring four mil has been examin crystals with o and Poccurrin and those from both hemihedra obtained by was for impurities, y Cb,O, Tic N.C. 19.48 29. S.C. 19.37 28.9 Prof. Rowland mitted for micr

The

dium.
auerlite from F

rare minerals.
composition:
=1.78; H,O=
drally hemihed
sometimes in t
Analysis: Si
Hidden 19 also
Manitou, Colo
four new local
ciated with all
zircon, in the
at the Grassy
gold placers
Landbo, Norw

A partial ana
52.53 per cen
substances.-

the Nickel P nodules of a green in mass is 5, and der PO, FeO 38.64 25.05

17 Ib., May, I 18 Cf. Amer.. 19 Ib., p. 439. 20 Headdon.

curring four miles from Marietta, S. C., and in Henderson Co., N. C. has been examined by these gentlemen, who find it forming tabular crystals with ∞P largely developed, and the new forms oP, P∞, and P occurring on it. Several of the crystals are apparently twins, and those from South Carolina, when doubly terminated, appear to be both hemihedral and hemimorphic. The material for analysis was obtained by washing kaolinized coarse granite. This, when corrected for impurities, yielded :

2

Cb,О, TiO, YO, (etc.) FeO UO, PbO Fe,О, CaO H2O Ins. SiO, N. C. 19.48 29.31 27.55 2.87 13.77

=

5.18 S. C. 19.37 28.51 21.23 2.47 19.47 .46 .18 .68 4.46 .12 I.OI Prof. Rowland, to whom the South Carolina specimens were submitted for microscopic study, found in them large amounts of scandium. The same investigators 17 have examined lemon-yellow auerlite from Price's Land, Henderson Co., N. C., and a few other rare minerals. The auerlite has a density of 4.051-4.075, and a composition: P2O,⇒ 8.58; SiO,=6.84; ThO,=72.16 (diff.); Fe,O, =1.78; H,O=10.64. Sulphohalite they find to be probably tetrahedrally hemihedral. The fayalite 18 of Cheyenne Mt., Colorado, occurs sometimes in the granite in masses weighing as much as ten pounds. Analysis: SiO, 27.66; FeO=65.79; MnO 4.17; Ca0.47. Mr. Hidden 19 also announces the discovery of bastnaesite and tysonite, near Manitou, Colorado, in a mass weighing over six kilograms, and gives four new localities for the occurrence of fergusonite, as follows: Associated with allanite, at Amelia Court House, Virginia; accompanying zircon, in the mines at Storeville, Anderson Co., South Carolina; at the Grassy Creek Mica Mine, in Mitchell Co., N. C.; and in the gold placers near Golden, Rutherford Co., N. C. The orangite of Landbö, Norway, is declared to be uranothorite. Its density is 4.322. A partial analysis gave 11.97 per cent. H,O; 18.50 per cent. SiO,; 52.53 per cent. ThO2; 9 per cent. UO,, and small quantities of other substances. Associated with beryl and spodumene in the granite of the Nickel Plate tin claim, in Pennington Co., South Dakota, are nodules of a phosphate near triphyllite in composition. It is dark green in mass, and light yellowish-green in thin splinters. Its hardness is 5, and density 3.612. Analysis 20 yielded :

PO, FeO MnO CaO

5

MgO Na, K,O

Li2O F Ign. Gangue

38.64 25.05 15.54 5.53 1.50 7.46 2.00 .28 .69 .73 2.47

17 Ib., May, 1891, p. 438.

18 Cf. Amer. Jour. Sci., March, 1885, p. 25.

19 Ib., p. 439.

20 Headdon. Amer. Jour. Sci., May, 1891, p. 416.

10

=

-Penfield 21 has analyzed an aurichalcite, occurring in narrow seams in an impure limonite from Utah, which yielded an average: CO, CuO ZnO H2O CaO Dens. 16.36 19.37 53.09 9.92 .61 3.57 2RCO,3R(OH)2, in which R= Zn and Cu, with CuO:Zno=2:5.- -Inexhaustible beds of beauxite have been discovered near Little Rock, Arkansas, and near Benton in the same state. According to Branner 2 they are genetically related in some unknown way with eruptive granites. The material is pisolitic in structure. A partial analysis of one specimen gave: Al,O,=55.64; SiO, = 10.38: Fe20,=1.95; TiO2=3.50; Loss 27.62.—An analysis of halotrichite from Pitkin Co., Colorado, is given by Bailey 23 as follows: SO, AO, Fe,O, FeO

nant.

5.18

3

MgO HO at 100° H2O at over 100°

.17

33.10

12.94

33.46 12.98 1.60
Farrington 24 has carefully examined the Arizona azurites, on
which he finds the new forms 3P, 4P, 3P and P. Four distinct
types of crystals are recognized; one is pyramidal with 2P predomi-
The others are prismatic, dome-like, and lath-shaped. The
latter came from the Longfellow Mine, and are peculiar for their
ortho-diagonal elongation and the large development of the ortho-
dome P The axial relation calculated from the measurements of
the different types is a:b: c.85676: 1:.88603; P=87°36′36′′—The
very rare mineral pollucite has just been reported by Wells 25 as asso-
ciated with quartz crystals aud clay, and with psilomelane and a nearly
colorless calcium beryl at Hebron, Maine. The pollucite is in
irregular fragments, perfectly colorless, and as brilliant and transparent
as plate glass. Its index of refraction for sodium light is 1.5247, and
its density 2.976-2.985. Its analysis gave:

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-Columbite 26

corresponding to H,R'Al(SiO,),, with which formula all the analyses
of the Elba mineral may likewise be made to agree.-
crystals from the Bob Ingersoll Claim and the Etta Mine in the Black
Hills have a tabular habit with P predominating.Snow 27 re-
ports the occurrence of turquoise at several ancient workings near
Silver City, Grant Co., New Mexico.

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Ahrens
Arzruni
Backstrom
Bailey
Barbour
Harrois
Bauer
Baumhauer
Baurath
Beaugey
Becke
Behrens
Belowsky
Biake
Bey
Branner
Brogger
Brown
Boowning
Brush
Campbell
Clark
Cements
Chester
Czapski

Daba

Darapsky
Descicizeaux
Doriter

Bufet
Ferrier
Flink
Frenzel

Fri del, G.
Friedel, C.
Genth
Graeff
Gramont

Groth
Harada

Harrimann

Harrington

Headdon

Hensoldt

Hidden
Hillebrand
Hintze
Hyland
Kochs
JannetazZ
Lacroix

Lane
Lang
Laspeyres
Lawson

Lehmann,

0.

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