Brown microcrystal of the very rare mineral örebroite from the type and only known locality worldwide in Orebro (Sjögruvan, Grythyttan, Hällefors, Örebro County, Sweden). Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY 4.0
Örebroite
Örebroite is an IMA-recognized mineral species in the silicate class, with the chemical formula Mn²⁺₆(Sb⁵⁺Fe³⁺)(SiO₄)₂O₆.
It crystallizes in the hexagonal crystal system (space group P3). It is a member of the Welinite structural group.
Key properties: Mohs hardness 4; specific gravity 4.77; Reddish brown streak; Vitreous luster; optically uniaxial.
IMA symbol Öbr, IMA status: approved, named in 1985.
A fine-grained aggregate with antimonates.
It is found associated with Calcite, hausmannite, magnetite, dolomite.
Ä For the town of Orebro, Sweden, about 60 km southeast of the SjÄo mine.