Blue sharp crystals of the extremely rare henmilite associated to very pale pink buryatite from the only known locality worldwide for henmilite (Fuka Mine, Bitchu-cho, Takahashi, Honshu Island, Japan). Henmilite is a Ca-Cu borate and buryatite is a Ca sulphate-borate that has only been found in two localities worldwide. — Photo: David Hospital · CC BY-SA 4.0
Buryatite
Buryatite is an IMA-recognized mineral species in the silicate class, with the chemical formula Ca₃(Si,Fe³⁺,Al)(SO₄)B(OH)₄(OH,O)₆·12H₂O.
It crystallizes in the hexagonal crystal system (space group P31c). It is a member of the Ettringite structural group.
Key properties: Mohs hardness 2.5; specific gravity 1.895; White streak; Dull luster.
IMA symbol Buy, IMA status: approved, named in 2000.
From drill core containing frolovite veinlets in kurchatovite-sakhaite ore.
It is found associated with Calcite, magnetite, brucite, fluoborite.
The name is taken from the type locality.