In vitro weathering products of pyrite

Abstract

Fine grained natural pyrite concretions oxidize spontaneously under laboratory conditions. A solution of oxidation products in distilled water yields the following crystallization products upon evaporation (in order of formation): melanterite, rozenite, szomolnokite, rhomboclase, coquimbite, roemerite, a slightly basic ferric sulphate, and voltaite. The crystallization sequence is comparable to that found in natural environments where pyrite ores are oxidizing.