Yellow brown microcrystals of the rare Bi vanadate mineral schumacherite from Germany (Schneeberg, Erzgebirge, Saxony). Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY 4.0
Schumacherite
Schumacherite is an IMA-recognized mineral species in the vanadate class, with the chemical formula Bi₃O(VO₄)₂(OH).
It crystallizes in the triclinic crystal system (space group P-1).
Key properties: Mohs hardness 3; specific gravity 6.9; Adamantine luster; optically biaxial.
IMA symbol Shh, IMA status: approved, named in 1982.
Very rare, in the oxidized zone of Bi-rich hydrothermal deposits.
It is found associated with Pucherite, namibite, quartz (Schneeberg, Germany); bismutite, bismutoferrite, bismutostibiconite, koechlinite, namibite (Lodi #4 mine, California, USA).
The mineral was named to honor Professor Friedrich Schumacher (1884–1975), Universities of Freiberg and Bonn, Germany.