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and redingtonite. Cinnabar from the New Idria Mine, California, ash a prismatic or rhombohedral habit, with the basal plane and a series of rhombohedra and tetarto-trapezohedrons well developed. The crystals are made up of layers of dextro- and lævo-rotatory material. At Knoxville acicular crystals occur with -R, and R. They encrust metacinnabarite that occurs in seams in a vesicular marcasite. An analysis gave: HgS=98.48; FeS =.69; SiO,=.71. Analysis of redingtonite and knoxvillite yielded :

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Colerain

to be ea

harder

density

Fe0=

Cinnam

and a ro

Que., ha

in the fe

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Copiapite in soft masses and sulphur-yellow scales and crystalline particles contains:

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Stromeyerite from the Silver King Mine, San Bernardino county, Cal., has a specific gravity of 6. 28, a steel-gray color on a fresh fracture, and a composition: Ag=53.96; Cu= 28.58; Fe = .26; S = 15.51; Res 1.55. The rare chromium chlorite Kotschubeite is found in the serpentine at Green Valley, Cal., as thin, hexagonal plates arranged in rosettes. The plates are twinned monoclinic crystals, with an optical angle of about 30°, and an acute bisectrix nearly normal to OP. The type mineral from the Urals is in apparently hexagonal pyramids. The composition of the California mineral is:

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-In a note on some Canadian minerals Mr. Harrington 13 mentions the existence of göthite crystals, forming a velvety druse on hematite, calcite, and other minerals at Clifton, N. S. At the same place radiating needles of the iron compound are found capped with rhombohedra of calcite. One specimen yielded: Fe,O,= 88.92; Mn,O,=.14; H2O 10.20; SiO,=.32. A white to pale apple-green serpentine occurs as veins in a darker serpentine at an asbestos quarry near

13 Can. Record of Science, Vol. IV., No. 2, 1890.

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vicinity

nature.

the west

are imbe northwe recent b

are the

Peru, M
Va.; (3

the Wate
SiO, A

(1) 77.29

(2) 35-35

(3) 27.41

(4) 47.28 3

Triplite, ALO, F 8.74

besides t 14 Can. A

15 Bull.

1891.]

Mineralogy and Petrography.

663

Coleraine, in the Eastern Townships. When first mined it is so soft as to be easily squeezed between the fingers, but on exposure it becomes harder until a hardness of 3.5 or more is reached. It then has a density of 2.514, and a composition: SiO, 43.13; MgO= 42.05; FeO.37; H,O= 13.88, with traces of MnO, NiO, and CaO. Cinnamon garnet from Ottawa county, Ont., has a density of 3.58, and a rose-red almandine from the Laurentian gneiss at Murray Bay, Que., has a specific gravity of 2.59. Small red spessartites," imbedded in the feldspar and muscovite of a coarse granite vein at Villeneuve Mine, Ottawa county, are much heavier. Sp. gr. = 4.117. The composition of these is:

SiO, Al,O, Fe,O, Cinnamon 36.22 18.23 7.17 Almandine 37.97 22.44 2.39 Spessartite 36.30 19.20

FeO MnO CaO MgO Loss .63 37.39 tr. .70 26.12 1.18 5.27 5.42 10.66 30.06 3.07 .43 .31

From the dump heaps of the Grant and Emerald Mines, in Buckingham, in the same county, specimens of mountain cork and mountain leather were obtained that yielded :

SiO, Al,O, Fe,O, FeO MnO CaO MgO Loss Sp. Gr. 53.99 .55 1.00 10.99 2.19 12.53 16.25 2.56 3.05 Since pseudomorphs of asbestos after pyroxene are found in the vicinity, it is thought that the material analyzed may be of the same nature. Dawsonite and ittnerite occur at the Corporation Quarry, on the west side of Montreal Mountain, and fine chalcedony concretions are imbedded in the clay between Irvine and the Cypress Hills, in the northwest territory. The analyses of several minerals are given in a recent bulletin of the U. S. Geol. Survey, 15 among which the following are the most interesting: (1) petalite, from the spodumene locality at Peru, Me.; (2) spessartite, from the Mica Mine, Amelia county, Va.; (3) willemmite, Trotter Mine, Franklin, N. J.; (4) kaolin, from the Waterfall Mine, Gunnison county, Col.

SiO2 Al2O3 Fe2O3 FeO MnO ZnO CaO Na2O K2O Li2O P2O, H2O and Loss (1) 77.29 16.95 tr. 2.39 tr. 2.62

tr.

(2) 35.35 20.41 2.75 1.75 38.70

(3) 27.41

(4) 47.28 36.19 tr.

[blocks in formation]

1.03

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Triplite, from a tin mine near Rapid City, S. Dak., gave:

Al,O, Fe,O, FeO MnO CaO Na,O P,O, H2O F SiO, Cl Co, 8.74 2.36 1.97 29.13 6.72 5.25 39.68 3.67 2.35 .43 .25 .26 besides traces of MgO and K,O, and .13 per cent. LiO,.

14 Can. Record of Science, October, 1890, p. 225.

15 Bull. No. 60, U. S. Geol. Survey, pp. 129-137.

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