Inorganic substance with the chemical formula Ag2S belonging to the class of binary compounds.

Can also be regarded as a salt of silver, and hydrogen sulphide. Occurs in nature as the mineral argentite or acanthite. At temperatures below 179C, the orthorhombic (or monoclinic) black (or dark gray), prisms (density 7.326 g/cm3), which corresponds to the natural acanthite. And at a temperature above 179C - the black (or dark gray) cubic crystals (density of 7.317 g/cm3), which corresponds to natural argentite. m.p. = 827 ° C. Slightly soluble in water OL (Ag2S) = 4,2.10-50 (t = 25oC) ammonia, alkali metal thiosulfate. Dissolved in nitric acid and alkali metal cyanide solutions. Can be prepared by reaction of silver and its compounds with sulfur, hydrogen sulfide or sulfide.

Physico-chemical data of Silver sulphide (CAS 21548-73-2):