Sphalerite indium

Zinc sulfide, ZnS, sphalerite (zinc blende) zinc sulfide, ZnS, wurtzite zinc selenide, ZnSe zinc telluride, ZnTe, cubic zinc telluride, ZnTe, hexagonal zinc polonide, ZnPo zinc aluminum selenide, ZnAl2Se4 zinc indium selenide, ZnIn2Se4 zinc indium telluride, Znhi2Te4. 

Occurrence. Indium is widely spread in nature, generally in very low concentrations (0.1 ppm, earth s crust). Indium is present as a trace element in many minerals, such as sphalerite. 

The occurrence of indium-minerals is very rare in general, and indium substitutes in base metal sulfide minerals for elements with similar ionic radii. The most common In-bearing minerals are sphalerite where In is substituting for Zn and Fe, stannite, kesterite and cassiterite where In Is replacing Sn and Fe (Shwarz-Schampera Herzig 2002). 

Indium concentrations in the polymetallic veins show a wide range (3.4 to 1184ppm In, Table 1). Based on the correlation coefficients of ore geochemistry, significant Indium (up to 1184 ppm) is related to the Ps2 mineralization stage and closely associated with Fe-rich sphalerite, but also with ferrokesterite. There are important In anomalies in Psi (up to 159.4 ppm) that are related to the Sn minerals, cassiterite, ferrokesterite and stannite (Crespi 2006). 

Indium is associated with both stages, but is concentrated in Ps2 related mainly with Zn (Fe-rich sphalerite) and minor association with Sn (ferrokesterite). For Psi, Indium is associated with Sn, present... 

World mine production of zinc is 9 Mt, with almost all of it derived from sphalerite [(Zn,Fe)S], which is also the principal primary source of cadmium and several other metals, such as germanium and indium. China and Australia are the largest producers, but several other countries mine significant amounts. About half of the annual consumption is for the manufacture of galvanized products to resist corrosion, primarily in the automotive and construction industries. 

Indium By-product from sphalerite Electronics, LCD screens... 

Zinc (0.02% of the earth s crust) occurs almost entirely as ZnS this has two forms (Fig. 277), the much commoner cubic zinc blende or sphalerite, and the rarer, hexagonal wurtzite (p. 149). Iron and cadmium are nearly always present as substitutional impurities and the ore also serves to concentrate a number of much rarer elements such as indium, gallium and germanium. The sulphide is easily converted to oxide by roasting in air. 

The common sources of indium are the minerals dark sphalerite, christophite, and marmatite. Indium is also found in small amounts in manganese, tungsten, zinc, and tin ores. Rarely found as a free element, indium is commonly associated with gallium in tin and zinc ores. The main commercial source for indium is from zinc smelter flue dusts (Smith etal. 1977). Enrichment of indium from zinc residues is performed by acid leaching followed by chemical separation processes. Aqueous electrolysis of indium salts yields a final metal of 99.9% purity. Canada has the greatest resources of indium with approximately 27% of the world s reserves (based on estimated indium content of zinc reserves) and the United States has about 12% of the world reserves (Brown 2000). In recent years, there have been major improvements in the recovery, refining and recycling of... 

Extensive regions of homogeneous solid solutions close to indium arsenide were established by physicochemical methods of analysis in the following quaternary systems InAs-CdS, InAs-CdSe, InAs-CdTe, InAs-ZnS, InAs-ZnSe, InAs-ZnTe. All the melts crystallize in the sphalerite structure and exhibit a linear relationship between the lattice constant and composition. The results ate presented of studies of the electrical conductivity, the Hall effect, and the thermoelectric power, and of electron-microscope studies of the cleaved surfaces of the alloys. 

Indium is present in sphalerite and galena (lead glance) regularly in parts-per-milHon quantities, but actual indium minerals are very rare. Ores with high indium contents (0.1-1%) are found in Bolivia, England (CornwaU) and Canada (Brunswick). The... 

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