Name: Named in 1845 by Wilhelm Karl von Haidinger after an Arabic or Moorish name applied to pyrite and similar metallic bronze colored minerals. Johnathan Hill used the same name in 1771, but his usage was indiscriminate and was a term for any massive “pyrites” or mundic.
Isostructural with: Safflorite
Occurrences of Marcasite
Geological Setting: Most frequently found in sedimentary rocks and coal beds, as a replacement mineral forming fossils, it is a mineral of low-temperature, near-surface, environments, forming from acid solutions. Pyrite, the more stable form of FeS^2, forms under conditions of higher temperatures and lower acidity or alkaline environments.
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