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Berthierite

Berthierite
Berthierite.jpg
Berthierite
General
Category Mineral
Formula
(repeating unit)
FeSb2S4
Strunz classification 2.HA.20
Crystal system Orthorhombic
Crystal class Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
Space group Pnam
Identification
Color steel grey
Cleavage poor/indistinct
Mohs scale hardness 2-3
Luster metallic
Diaphaneity opaque
Specific gravity 4.64

Berthierite is a mineral, a sulfide of iron and antimony with formula FeSb2S4. It is steel grey in colour with a metallic lustre which can be covered by an iridescent tarnish. Because of its appearance it is often mistaken for stibnite.

It was discovered in France in 1827 and named for the French chemist, Pierre Berthier (1782–1861).


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