Black microcrystals of the extremely rare Ti-V-As-Sb oxide mineral hemloite from the type and only known locality worldwide in Page Williams mine, Hemlo deposit, Canada, in a quartz barian microcline matrix. Analyzed specimen by SEM/EDS by the former owner of the specimen (the Vandenbroucke Museum). Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Hemloite
Hemloite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula (Ti,V³⁺,Fe³⁺,Al)₁₂As³⁺₂O₂₃(OH).
It crystallizes in the triclinic crystal system (space group P-1).
Key properties: Mohs hardness 6.5–7; specific gravity 4.613; Black streak; Metallic to submetallic luster; optically biaxial.
IMA symbol Hlo, IMA status: approved, named in 1987.
Found in a hydrothermal gold deposit.
It is found associated with Quartz, barian microcline, pyrite, molybdenite, sphalerite, arsenopyrite, vanadian muscovite, rutile, titanite.
The name refers to the Hemlo deposit, Ontario, Canada, where it occurs.