Sulfosalts

R. W. FairbriiXjE, Encyclopedia of Geochemistry and Environmental Sciences, Van Nostrand, New York, 1972.. See sections on Geochemical Classification of the Elements Sulfates Sulfate Reduction-Microbial Sulfides Sulfosalts Sulfur Sulfur Cycle Sulfur Isotope Fractionation in Biological Processes, etc., pp. 1123 - 58. 

It is likely that the lead and sulfur atoms in most of the lead sulfarsenites and related minerals have the tercovalent argonic structures Pb—- and S y+, as in galena. Nowacki (1969) has published a valuable summary of results of structural studies of the so-called sulfosalt minerals, in relation to a system of classification of the structures that he has developed. Many structures of sulfide minerals have been determined by him and his coworkers. 

The common Ag-Au minerals are argentite, As-Se minerals and Ag sulfosalts (polybasite, pyrargyrite, pearceite). 

The common Ag minerals are argentite, and Ag sulfosalts (pyrargyrite, polybasite). Ag sulfosalts are abundant in the late stage of mineralization and argentite occurs in the early stage of mineralization (e.g., Ohe-Inakuraishi, Toyoha). 

Figure 4.26 Chemical twinning in the lead bismuth sulfosalts (a) idealized structure of galena, PbS, projected onto (110) (b) idealized structure of heyrovskyite and (c) idealized structure of lillianite. Shaded diamonds represent MS6 octahedra, those at a higher level shown lighter. Bi atoms are represented by shaded spheres, those at a higher level shown lighter. The twin planes are 113 with respect to the galena cell, and the arrows indicate planes of close-packed S atoms.

Silurian Mt. Wills Granite. Gold mineralisation is structurally-hosted and accompanied by the presence of pyrite, arsenopyrite, sphalerite, aurostibite, and a variety of sulfosalts (Crohn 1958). Gangue phases include quartz and ferroan dolomite. 

Wagner, T., Boyce, A. J., and Fallick, A. E. (2002). Laser combustion analysis of <534S of sulfosalt minerals determination of the fractionation systematics and some crystal-chemical considerations. Geochimica et Cosmochimica Acta 66 2855-2863. 

Mineralization was represented by quartz-chlorite-carbonate-sulfide veins with visible chalcopyrite, galena, sphalerite, pyrrhotite, cobaltite, limonite and malachite. Fractures filled by veins are identified on aerial photos as one submeridional zone up to 20 m thick and 500 m long. The northeastern linear system represented by a shear zone containing veinlets with arsenopyrite, bismuthine, gold and silver sulfosalts. Twelve veins that differ in extent and intensity of mineralization were discovered, with some veins yielding 3 wt. % Sn, 3 wt. % Cu, and up to 250 g/t Ag. 

Anomalous values of Au, Cu, Sn, Bi, As, and W in the Psi indicate the precipitation of high temperatures minerals and metals that are represented by a complex mineralogy. The correlation between Ag-Pb-Bi-Sb suggests the presence of different Ag-Pb-Bi sulfosalts correlation between Ag-Cu-Sb is associated with freibergite, argentotenantite, and tetrahedrite, while Sn-W is related to wolframite and cassiterite, and In-Sn-Sb with ferrokesterite, stannite and cassiterite. In Ps2 the In and Cd, are present in the Fe-rich sphalerite (Crespi 2006) showing a high correlation between In-Zn-Cd the correlation between In-Sn is associated with ferrokesterite. The presence of Ag-Pb sulfosalts is... 

The distribution of the metals in the veins is represented by two mineralization stages an early Psi characterized by the presence Sn sulfides, Ag-Pb-Bi sulfosalts, Ag-Cu sulfosalts with the highest concentration of Cu, Au, As, Sn, W and Bi, and a late PS2 that shows the highest values of Zn, Pb, Ag, In, Cd and Sb with Fe-rich sphalerite, galena and Ag-Pb sulfosalts. 

Zhang S, Meyer B, Moh GH, Scholz F (1995) Development of analytical procedures based on abrasive stripping coulometry and voltammetry for solid state phase microanalysis of natural and synthetic tin-, arsenic-, and antimony-bearing sulfosalts and sulfides of thalhum, tin, lead, and silver. Electroanalysis 7 319-328. 

Many simple minerals, especially simple salts like halite, NaCl, sulfides, sulfosalts and oxides, have structures based upon cubic or hexagonal closest-packed arrays of either cations or anions. Coordination geometries of metal ions in many of these kinds of minerals are thus confined to more or less regular octahedra and tetrahedra. The occupancy of the two types of sites is dictated by the stoichiometry of the mineral, the radius of the ions involved and their preferred coordination geometries. Coordination of cations in mineral species in terms of bonding and crystal field effects has been extensively reviewed.16-21 Comprehensive lists of ionic radii relevant to cation coordination geometries in minerals have also been compiled.16,21... 

Prsek, J., Mikus, T., Makovicky, E. and Chovan, M. (2005) Cuprobismutite, kupCfkite, hodrushite and associated sulfosalts from the black shale hosted Ni-Bi-As mineralization at Cierna Lehota, Slovakia. European Journal of Mineralogy, 17(1), 155-62. 

The crystallized sulfosalt is then decomposed at 400°C. with hydrogen according to the following equation ... 

Sulfosalts are compounds of one or more metals, a semi-metal and sulfur. Many sulfosalts are rare, but some of them are important ore minerals. 

An alloy is a mixture of two or more metals, or of a metal and a non-metal. Many minerals are natural alloys, being compounds of metals or a metal/ non-metal combination. Most of these fall into the native element, sulfide and sulfosalt mineral groups. 

Sulfosalt group(s) A range of complex Pyrargyrite (AgjSbS3) tetrahedrite... 

Although examples of minerals from most of the major groups of sulfides (Table 6.1) have been discussed in the preceding sections of this chapter, there are a number of phases particularly worth considering that do not fit into any of the above categories. These are the layer sulfide molybdenite (MoSj), the metal-excess sulfides of the pentlandite family [CojSg, (Ni,Fe)9Sg], and an example of a sulfosalt family in the form of the tetra-hedrite-tennantite minerals [ Cu3(Sb,As)4S 3]. 

Another interesting family, in this case of sulfosalt minerals, is that of the tetrahedrites. Natural tetrahedrites are described approximately by the formula where A = Cu,Ag B = Cu,Fe,Zn,Hg,Cd,Pb ... 

Determination of local environment of particular atoms in a solid. Applicable to 130 isotopes (e.g., in mineralogy, studies of Al applied to order-disorder phenomena studies of As, Sb, and Bi isotopes in sulfosalts applied to structural investigations)... 

The average crustal abundance of arsenic is 1.5mgkg . The element is strongly chaloco-phile. Approximately 60% of natural arsenic minerals are arsenates, 20% sulfides and sulfosalts, and the remaining 20% are arsenides. 

Mexico, the leading silver producer, obtains about half of its output from mines in which silver is the principal ore metal. Many of the mines are epithermal fissure veins, and most host a polymetallic assemblage whose exploitation is economically dependent on the high silver values. Although acanthite [Ag2S] and native silver predominate in some veins, in others much of the silver occurs in silver sulfosalts and as silver substitutions in tetrahedrite [(Cu,Fe,Ag)i2Sb4Si3] and other minerals. 

Primary minerals formed in the ore deposit prior to weathering and erosion, including a wide variety of metal sulfides and sulfosalts, metal oxides, metal- and alkaline-earth carbonates, sulfates, crystalline silica, clays, and other silicates. Many metal sulfides (especially iron sulfides such as pyrite), when exposed by erosion or mining to atmospheric oxygen and water, can form acid-rock drainage (ARD). 

SULFIDES and SULFOSALTS (sulfides, selenides, tellurides arsenides, anti-monides, bismuthides sulfarsenites, sulfantimonites, sulfbismuthites, etc.)... 

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