Greenockite cadmium sulfide

Sulfides and Selenides cadmium sulfide, amorphous t)rpe cadmium sulfide, greenockite type and greenockite cadmium sulfide, hawleyite type and hawleyite cadminm selenide the tertiary sulfides cadmium mercury sulfide, cadmium selenium sulfide and cadmium zinc sulfide. 

Cadmium sulfides and selenides group Cadmium sulfide, greenockite type Cadmium sulfide, hawleyite type Chrome yellow Budgen (1924) Fiedler Bayard (1986)... 

Cadminm sulfides and selenides group Cadmium sulfide, greenockite... 

Cadmium group Cadmium sulfides and selenides group Cadmium sulfide Greenockite Lithopone Titanium dioxide white Aurora yellow. Brilliant yellow, Cadmia-, Cadmium lithopone-. Cadmium sulfide lithopone-, Cadmolith-, Cadmopone-, Daffodil yellow-. Emerald green-, Jaune brilliant-. Lemon cadmium-, Mutrie yellow-. Neutral orange-. Orient yellow Radiant yellow... 

Greenockite, see Cadmium sulfide Gruenerite, see Iron(II) silicate(2—)... 

Cadmium sulfide [68859-25-6], CdS, Mr 144.48, occurs as greenockite or cadmium-blende in several natural deposits, which are, however, of no importance as pigments. The mineral crystallizes hexagonally in the wurtzite lattice (a-form). 

Uses Cadmium (Cd) (L. cadmia Gr. kadmeia, ancient name for calamine, zinc carbonate) was discovered by Stromeyer in 1817 through an impurity in zinc carbonate. Cadmium most often occurs in small quantities associated with zinc ores, such as sphalerite (ZnS). The important compounds used in industry are cadmium oxide (CdO), cadmium chloride (CdCl2), cadmium nitrate (CdfNCRh), cadmium sulfide (CdS), and cadmium sulfate (CdSC>4). Greenockite (CdS) is the only mineral of any consequence bearing cadmium. Cadmium is also obtained as a by-product in the treatment of zinc, copper, nonferrous metal industry, and lead ores. Cadmium is a highly toxic heavy metal that forms complex compounds with other metals and elements. 

Early attempts to prepare low-melting alloys with cadmium sulfide (its natural form, greenockite, is orange-yellow) encouraged further investigation... 

The only important ore of cadmium is greenockite, or cadmium sulfide (CdS). Most cadmium is obtained as a by-product of zinc refinement. 

Occurrence A greenockite (cadmium sulfide) ore containing zinc sulfide also in lead and copper ores containing zinc. Canada, central and western U.S., Peru, Australia, Mexico, Zaire. 

Cadmium occurs naturally as an insoluble sulfide (greenockite). It is found in this form combined with zinc in blende. Pure CdS is a yellow salt used in paint and fireworks. In industry, it is a raw material for nickel-cadmium batteries. 

Greenockite gre-n3- klt [Charles M. Cath-cart. Lord Greenock f 1859 Enghsh soldier] (1844) n. Naturally occurring cadmium sulfide mineral. 

The average lead content in the Earth s crust is 13mg/kg and cadmium content is 0.1 mg/kg. In nature, these metals are found mainly in sulfide and carbonate ores. Lead sulfide is known as galena (PbS), cadmium sulfide occurs in the rare ore greenockit (CdS), and both metals are present as admixtures in sphalerite (ZnS) and smithonite (ZnCOj). 

Although cadmium sulfide exists in two crystalline forms (hexagonal or greenockite type, and cubic or hawleyite type, qq.v.), an amorphous form may also be synthesised. This phase can reportedly coexist with the other crystalline forms at room temperature. According to Budgen (1924), amorphous cadmium sulfide may be formed either by the adding cadmium oxide to molten potassium thiocyanate, or by heating cadmium thiocyanate with acetic acid in a sealed tube at 250 C. 

Cadmium yellow Cadmium sulfide CdS Mineral (greenockite) +... 

Minerals dominated by cadmium are rare the sulfide CdS (greenockite), especially, is very rarely found. However, cadmium is widespread in zinc ores in low concentrations (0.2-0.4%) and is separated during processing of these ores and production of zinc. 

Although ranking 57th in abundance in the earth s crust tO. 15 ppm), cadmium is not encountered alone, but is always associated with zinc. The only known cadmium minerals are greenockite (sulfide) and otavite (carbonate), both minor constituents of sphalerite (zinc oxide) and smilhsoniie (zinc carbonate), respectively See also Greenockite Smithsonite and Sphalerite Blende. 

Cadmium is obtained mainly as a by-product in the smelting and refining of zinc it occurs to the amount of about one percent in many zinc ores. The sulfide of cadmium, CdS, is called greenockite. Cadmium is more volatile than zinc, and in the reduction of zinc oxide containing cadmium oxide it is concentrated in the first portions of dust collected in the receivers. 

Derivation (1) By passing hydrogen sulfide gas into a solution of a cadmium salt acidified with hydrochloric acid. The precipitate is filtered and dried. (2) Occurs naturally as greenockite. 

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