Violarite

Violarite (Fe2+Ni23+S4) is a supergene sulfide mineral associated with the weathering and oxidation of primary pentlandite nickel sulfide ore minerals. Violarite (Fe2+Ni23+S4) is a supergene sulfide mineral associated with the weathering and oxidation of primary pentlandite nickel sulfide ore minerals. Violarite crystallises in the isometric system, with a hardness of 4.5 to 5.5 and a specific gravity of about 4, is dark violet grey to copper-red, often with verdigris and patina from associated copper and arsenic sulfides, and is typically in amorphous to massive infill of lower saprolite ultramafic lithologies. Violarite has a characteristic violet colour, hence the name from the Latin 'violaris' alluding to its colour especially when viewed in polished section under a microscope. Violarite is formed by oxidisation of primary sulfide assemblages in nickel sulfide mineralisation. The process of formation involves oxidation of Ni2+ and Fe2+ which is contained within the primary pentlandite-pyrrhotite-pyrite assemblage.