Pyritization in the shells of living bivalves

摘要: Pyrite with characteristic brass-yellow luster was found coating parts of the outer surface living Mercenaria mercenaria and Geukensia demissa in a Georgia tidal marsh. Sections through one shell revealed additional pyrite replacing aragonite layer, especially around fractures, borings, concentrations organic matrix. This is first report precipitation massive (metallic luster) modern sediments indication that pyritization can commence mollusk even before death mollusk.