This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 Excerpt: ...2J. Specific gravity, about 5-6. Optical.--Colour, scarlet-vermilion. Streak, scarlet. Lustre, adamantine. Microfragments transparent, with an extremely high refractive index (w = 2-98). Birefringence extremely high (w-= 0-27). Optical sign, negative. Blowpipe and chemical.--Sulphide of silver and arsenic (3Ag2S ' ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 Excerpt: ...2J. Specific gravity, about 5-6. Optical.--Colour, scarlet-vermilion. Streak, scarlet. Lustre, adamantine. Microfragments transparent, with an extremely high refractive index (w = 2-98). Birefringence extremely high (w-= 0-27). Optical sign, negative. Blowpipe and chemical.--Sulphide of silver and arsenic (3Ag2S ' As2S3) with 65-95 per cent, of silver. Fusibility, 1. In closed tube yields a sublimate of arsenic sulphide. Smell of sulphur dioxide in open tube and a sublimate of arsenic, which is more volatile than that of the antimony oxide yielded by pyrargyrite. On charcoal yields a button of metallic silver. Decomposed by nitric acid, with separation of sulphur. Stephanite (named after Archduke Stephen of Austria. Also called brittle silver-ore). General.--Orthorhombic; in flat or elongated six-sided prisms, terminated by basal plane; but usually massive, and compact, or in a disseminated form. Fracture, conchoidal or uneven. Hardness, 2i. Specific gravity, about 6-2. Optical.--Colour, greyish black. Streak, greyish black. Lustre, metallic. Opaque. Chemical and, blowpipe.--Sulphide of silver and antimony (5Ag2S 1 Sb2S3), with 68-5 per cent, of silver. Fusibility, 1. Charcoal reactions, and chemical behaviour generally, like those for pyrargyrite. Polybasite (Gr. polys, many, and basis, base, signifying the presence of many metallic bases). General.--Monoclinic, with tabular crystals simulating hexagonal form. Also massive and disseminated. Fracture, uneven. Hardness, 21. Specific gravity, about 6-2. Optical.--Colour and streak, iron-black. Lustre, metallic. Microfragments translucent and reddish, with a very high refractive index, exceeding 1-9. Chemical and blowpipe.--Sulphide of silver, copper and antimony 9(Ag, Cu)2S 'Sb2Sg, with about 70 per cent, of ...
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Add this copy of Economic Mineralogy: a Practical Guide to the Study of to cart. $58.91, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2010 by Nabu Press.
Add this copy of Economic Mineralogy: a Practical Guide to the Study of to cart. $67.74, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2016 by Palala Press.
