Pyrite ↗
Mineral species
Pyrite catches light with a brass-yellow metallic surface. Cubes and other crisp crystal shapes make even a small collector specimen rewarding to study.
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Crystal Guide / All families
Same formula, different structures
Iron disulfide polymorphs.
Pyrite and marcasite are distinct FeS₂ minerals. Their different stability and structures matter for care.
Keep each chapter’s scientific identity: a family, species, variety, trade label, rock and fossil are different kinds of names.
Marcasite ↗
Mineral species
Marcasite is an iron sulfide species with metallic luster. It shares the FeS₂ formula with pyrite, but the two have different crystal structures.
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