sulfosalt

sulfosalt

also spelled  sulphosalt 

       Sulfosalts Sulfosaltsany of an extensive group of minerals, mostly rare species, marked by some of the most complicated atomic and crystal structures known to inorganic chemistry. They conform to the general composition AmBnXp, in which m, n, and p are integers; A may be lead, silver, thallium, or copper; B may be antimony, arsenic, bismuth, tin, or germanium; and X may be sulfur or selenium. Formerly it was believed that the sulfosalts were salts of complex hypothetical thioantimonic or thioarsenic acids (e.g., HSbS2, H18As4S15, H3AsS3), but X-ray diffraction analyses indicate that the atomic structures of many sulfosalts are based on structural fragments of simpler compounds such as galena (lead sulfide; PbS) blocks and stibnite (antimony trisulfide; Sb2S3) sheets. No encompassing theory has been evolved to rationalize many of these curious compounds. The complexity of many of the structures evidently results from their having crystallized at low temperatures and the consequent high degree of ordering of the metal atoms. Syntheses of such compositions at higher temperature usually result in structures simpler than the complicated low-temperature forms.

      Although sulfosalts are much rarer than the sulfide minerals with which they are often associated, some localities are truly remarkable for the variety of species encountered. At the Lengenbach Mine in Switzerland, for example, more than 30 distinct species have been recognized, 15 of which are not found elsewhere. Most sulfosalts have formed at low temperature in open cavities, usually in association with copper–zinc–arsenic sulfide ores. Very often they occur in cavities of calcite and dolomite, as at the Lengenbach Mine. Most are lead gray in colour with a metallic lustre, brittle (rarely malleable), crystalline, and difficult to tell apart without recourse to X-ray diffraction and electron microprobe analyses. The thallium-bearing sulfosalts often are deep red and transparent, as sometimes are the sulfosalts of silver.

      Although under exceptional circumstances some sulfosalts may constitute silver ores (i.e., proustite, pyrargyrite, and stephanite), and other species have constituted ores of silver (in minor amounts), mercury, arsenic, and antimony (i.e., boulangerite, livingstonite, enargite, and tennantite-tetrahedrite), their economic importance is trivial. Aside from mineralogical curiosities, the sulfosalts are of interest because their electronic properties are related to those of semiconductors.

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Universalium. 2010.

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  • Sulfosalt minerals — are those complex sulfide minerals with the general formula: AmBnSp; where A represents a metal such as copper, lead, or silver; B represents a semi metal such as arsenic, antimony or bismuth; and S is sulfur or rarely selenium. In the more… …   Wikipedia

  • sulfosalt — adjective Being a complex sulfide mineral with certain proportions of a metal, a semi metal, and sulfur (or, rarely, selenium) …   Wiktionary

  • sulfosalt — sul·fo·salt …   English syllables

  • sulfosalt — ˈsəlfəˌsȯlt noun Etymology: International Scientific Vocabulary sulf + salt : a compound (as tetrahedrite) that is either a salt of an inorganic thio acid or a double or multiple sulfide …   Useful english dictionary

  • Cobaltite — from Sweden General Category Sulfosalt mineral Chemical formula …   Wikipedia

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  • Classification of minerals — This list gives an overview of the classification of minerals (non silicates) and includes mostly IMA recognized minerals and its groupings. This list complements the alphabetical list on List of minerals (complete) and List of minerals. Rocks,… …   Wikipedia

  • Tennantite — Infobox mineral name = Tennantite category = Mineral: sulfosalt boxwidth = boxbgcolor = imagesize = caption = A sample of tennantite formula = Cu12As4S13 molweight = 1,471.40 gm color = Steel gray to iron gray habit = massive to well formed… …   Wikipedia

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