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nomelane from Antwerp, New York; 16. Calamine from the Bertha mine, Pulaski Co., Virginia; 17. Titanite from Statesville, North Carolina; 18. Vanadinite from Wanlockhead, Scotland; 19. Annabergite from the Gem mine, Silver Cliff, Colorado. B. H. B.

Mineralogical Notes. By E. S. DANA (Amer. J. Sci., 32, 386390). The author gives the results of a crystallographical investigation of the following minerals:

1. Columbite from Standish, Maine.-The results of the author's examination of this mineral have already been published (this vol., . 20).

2. Diaspore from Newlin, Pennsylvania. The crystal examined is the finest ever found at the locality. It is prismatic in habit and showed the following planes:-P∞, ∞P2, ∞P2, ∞P5, and §P; the last pyramid being new to the species. On crystals of diaspore from Chester, Massachusetts, the author has observed the planes 1P and 1P2, new to the species.

3. Zincite. The knowledge of the crystals of zinc oxide has hitherto rested on observations of artificial crystals, the native mineral showing usually only massive forms. The cabinet of Mr. C. S. Bement contains several specimens of zincite from Stirling Hill, New Jersey, showing distinct crystals. The angles measured show a fair agreement with the angles of the artificial forms.

4. Sulphur.-A specimen of native sulphur from Rabbit Hollow, in the cabinet of Professor Brush, is interesting on account of the complexity of its form. Fifteen planes were observed; of these P3 and P are new to the species.

B. H. B.

Copper Mineral from Sunnerskog, Sweden. By G. LINDSTRÖM (Zeit. Kryst. Min., 12, 512-513).-The mineral is dark indigo-blue, with a blue streak and faint metallic lustre. Analysis gave the following results:

Cu. 74.29

S. 24.22

Fe2O3. CaO. Insol. Total.
0.10 0.59 0.51 99.71

A mineral analysed by Hahn, and named carmenite, had the same composition. It was, however, regarded by Dana as an impure copper glance, mixed with covelline. B. H. B.

Galenobismuthite containing Selenium from the Falun Mine. By M. WEIBULL (Zeit. Kryst. Min., 12, 511-512).-Galenobismuthite containing selenium was first observed in the quartz at the Falun Mine in Sweden. Its occurrence is of practical importance, as it has been proved that the native gold is always accompanied by this mineral at Falun. The mineral has a perfect cleavage; H. 3. Thin plates are flexible, but scarcely elastic. The colour is a steel grey; sp. gr. 6.97. Analysis gave the following results :

Bi. 49.73

Pb.
Cu.
Fe.
S.
24.62 0.77 0.61 9.82

The formula is thus PbS,BigS, + PbS,BigSea.

Total.

99.66

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Se. 13.61

The mineral is

probably isomorphous, with the lead-bismuth glance described by H. Sjögren.

This mineral has also been analysed by A. Genth (Zeit. Kryst. Min., 12, 487-488), the mean of five analyses giving the following results, after 3'96 to 8.8 per cent. of impurities had been subtracted :

S.

Bi.
Pb. Ag.
Se.
49.88 27.88 0.33 9.75 12:43

Total.

100.27
B. H. B.

Emmonsite, an Iron Telluride. By W. F. HILLEBRAND (Zeit. Kryst. Min., 12, 492-493).—This new mineral from Colorado occurs in yellowish-green scales in a hard brown, vein-mass, consisting of lead carbonate, quartz, and a brown substance containing iron and tellurium. The mineral is probably monosymmetric. The quantity of mineral available for analysis was very small. Three analyses of the brown substance gave the results under I, II, III; an analysis of the green particles carefully picked out, but still not pure, gave the results under IV. The mean results, probably the most correct, are given under V, 0.53 per cent. of selenium having been subtracted:

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In Analysis I, 3-28 per cent. of water was found, and in Analysis IV 1.94 of ZnO and 0.56 of CaO. The mineral is a ferri-telluride. It has been named in honour of Mr. S. J. Emmons, of the U.S. Geological Survey. B. H. B.

Elpasolite, a New Mineral. By W. J. CROSS and W. J. HILLEBRAND (Zeit. Kryst. Min., 12, 495). This is a new Colorado mineral, named after the county (El Paso) in which it was found. It occurs in cavities in massive pachnolite, in the form of compact masses, on which are planted indistinct, isometric crystals. Analysis gave the following results:

AJ. Ca. Mg. K. Na. 11.32 0.72 0.22 28.94 9.90

F.

Total.

98.08

(46.98)

The determination of the alkalis is only an approximation, and the fluorine is calculated on the assumption that it is completely combined with metals. It is suggested that the mineral should be regarded as a cryolite, in which two-thirds of the potassium is replaced by sodium. B. H. B.

Gearksutite from Ivigtut, Greenland. By A. E. NORDENSKIÖLD (Zeit. Kryst. Min., 12, 513-514).-The mineral is, according to the author, of recent formation, being due to the action of calcareous water on the water circulating in the fissures of the cryolite deposit. Analysis gave results identical with those obtained by Cross and Hillebrand (Abstr., 1884, 21), the formula being CaF2 +(AIF) (AIH2O2) + H2O. B. H. B.

Chemical Composition of Ralstonite. By S. L. PENFIELD and D. N. HARPER (Amer. J. Sci., 32, 380-385).-Analyses of the rare mineral ralstonite have been published by Nordenskiöld, Penfield, and Brandt. The authors have now made an analysis of a specimen of ralstonite associated with thomsenolite from Arksut Fjord, Greenland, the results being as follows:

Ca.

Al.

F.

Mg. Na. K.
4:39 4.27 0.12 0.03 24.25 39.91

H2O. Total. 18.73 91.70

This ratio being

The ratio of (MgNa,K2): Al 1:3 nearly. assumed to be correct, the ratio of the fluorine necessary to unite with the metals should be 11, whereas only 7.56 was found. The assump

tion that hydroxyl replaces fluorine not only makes up for the deficiency in the analysis, but also leads to a very satisfactory ratio. The assumption is also well supported by actual experiment. Using the actual water of crystallisation and hydroxyl determinations, and determining the fluorine by difference, the latter part of the analysis would be as follows::

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Assuming these conclusions to be correct, the mineral is an isomorphous mixture of (MgNa2) Al3F1,2H2O and (MgNa2) Al(OH)11 +2H2O. B. H. B.

Brucite from the Ural. By A. A. LöscH (Zeit. Kryst. Min., 12, 514). The mineral occurs with chlorite, calcite, perowskite, forsterite, and waluewite at the Nikolaje-Maximilianoffski Mine; sp. gr. = 2.388. Analysis gave the following results:

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B. H. B.
By A.

Artificial Production of Zincite and Willemite. GORGEU (Compt. rend., 104, 120-123).-When zinc sulphate is gradually heated to bright redness, it yields zinc oxide in small crystals which are more readily obtained if the zinc salt is mixed with an equivalent quantity of an alkaline sulphate. Decomposition is then less rapid and the crystals separate in the fused mass. Before decomposition is complete, the product is cooled and extracted with water, when zinc oxide is left in heavy, transparent, nacreous, greenishyellow or greenish, hexagonal prisms which, like the crystals of zincite, belong to the hexagonal system. In hardness and sp. gr. (5.5) the artificial crystals are identical with the natural oxide. Zinc nitrate also yields good crystals if only heated to partial decomposition, and the crystals are also obtained by heating equal parts of zinc fluoride and potassium fluoride in presence of aqueous

vapour.

Willemite, SiO2,2ZnO, is obtained when an intimate mixture of zinc sulphate with 0.5-1 equivalent of an alkaline sulphate and one-thirtieth of their weight of hydrated silica is heated for an hour

VOL. LII.

2 a

at a temperature sufficient to cause a slight but regular evolution of sulphurous anhydride. The fused mass is treated with water, which leaves a residue of tridymite and basic zinc sulphate with strongly birefractive crystals of willemite, which form hexagonal prisms with obtuse rhombohedral terminations. In hardness (5.5), sp. gr. (4.25), and general properties, the artificial crystals are identical with those of the natural mineral. Calcined silica and sand will give the same results, but the action is much slower.

No acid zinc silicate was obtained even with an excess of silica.

When a mixture of zinc chloride and an alkaline chloride with silica is heated in presence of water-vapour, crystals of the composition SiO2,2ZnO, are obtained, but their exact form could not be determined. C. H. B.

Goslarite from Montana. By R. PEARCE (Zeit. Kryst. Min., 12, 494).-Goslarite occurs in long, acicular crystals in some old workings, 400 feet deep, in the Gagnon Mine, Butte City, Montana. Analysis gave the following results :

ZnO.

SO3.
CuO. MnO,FeO.
28.09 (27.56) 0.12 0:30

H2O.

43.93

Total. 100.00

B. H. B. By A. SJÖGREN

Place of Spodiosite in the Mineral System. (Zeit. Kryst. Min., 12, 512).—In consequence of the chemical and crystallographical resemblance between spodiosite and kjerulfine, the author suggests that the two minerals may be isomorphous compounds, thus:

Kjerulfine
Spodiosite

...

Mg.F.PO
Ca2F PO1.

The planes of spodiosite calculated from the axial ratio of kjerulfine would be coP, coPco, -2P, +2P, 4Pcs. B. H. B.

Sarkinite, a New Manganese Arsenate. By A. SJÖGREN (Zeit. Kryst. Min., 12, 514).—This mineral occurs in veins of white calcite at Pajsberg, in Sweden. It has a greasy lustre, and is of a bright flesh colour, hence its name, from oάpkivos, fleshy. H. = 4 to 5. Sp. gr. 414 to 4:15. The mineral is brittle, giving a bright red powder. On heating, the powder becomes first grey, then black, and, when strongly ignited, a brownish-black. The crystalline system is unknown, probably monosymmetric. The mean of two analyses gives the following figures:

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B. H. B.

Polyarsenite, a New Mineral. By L. J. IGELSTRÖM (Zeit. Kryst.

found at the Sjö mine, in the

Min., 12, 515).-The mineral was parish of Grythytta, Örebro, Sweden.

It is a hydrated manganese

arsenate, of a reddish-yellow colour, translucent, massive, and without distinct cleavage, or crystal planes. It occurs with hæmatostibiite (a manganese antimoniate) in calcite veins in a mass of tephroite. Sp. gr. 4.085. Analysis gave the following results:

H,O. CO.. As2Os Sb2O5. MnO. FeO. CaO. MgO. Total. 3.15 3.51 39.23 1.37 49.88 trace 2.85 0.77 100.76 Formula: (MnO),As2O ̧ + H2O.

B. H. B. Crystallised Vanadinite from Arizona and New Mexico. By S. L. PENFIELD (Amer. J. Sci., 32, 441-443).-The crystals of vanadinite from Pinal Co., Arizona, are small, seldom over 1 mm. in length, of a deep red colour, and usually show the very simple combinations mentioned by W. P. Blake (Amer. J. Sci., 22, 410). A few highly modified crystals were found possessing pyramidal hemihedral forms, which are of interest because these forms have rarely been observed in this species. From the best measurements, the axial ratio a: c 1: 0·71121 was obtained. This agrees closely with the ratios given by Schabus, 10-71157, and by Vrba, 1: 0-7112177. The measured angles agree closely with those calculated from the axial ratio. The crystals contain but a trace of As 05.

=

The crystals from the Sierra Grand Mine, Lake Valley, New Mexico, are straw-yellow in colour. The crystals give distinct V2O5 and As2O, reactions, thus corresponding exactly with the description given by F. A. Genth and G. vom Rath of the species named by them endlichite. The axial ratio was found to be ac 1: 0·7495. The measured angles do not agree well with those calculated from the axial ratio. The presence of As2O, in the mineral must therefore tend to increase the length of the vertical axis. B. H. B..

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Columbite from Colorado. By W. P. HEADDEN (Zeit. Kryst. Min., 12, 494). A mineral, hitherto regarded as tin ore, from Turkey Creek, Jefferson Co., Colorado, is found to be columbite rich in manganese. Sp. gr. 5:48. Analysis gave the following results:

Nb2O WO3 + SnOg. FeO.
77.83
1.00

9.92

MnO. 11.23

Total.
99.98

B. H. B. By G. LINDSTRÖM (Zeit.

Phosphoric Anhydride in Felspar. Kryst. Min., 12, 513).-The author gives two analyses of felspar from Tammela and Skogböle in Finland. They present nothing worthy of note, with the exception of the phosphoric anhydride found by the author. In one case the percentage is 0.72, and in the other 0:58. Thin sections of the mineral analysed were found to contain a small quantity of apatite. The author is, however, of opinion that the phosphoric anhydride must also be present in some other less soluble compound. B. H. B.

Lithia Micas. By F. W. CLARKE (Amer. J. Sci., 32, 353-361). 1. The Lepidolites of Maine.-In the western part of Maine, there are

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