Black crystals of the rare Fe silicate mineral laihunite from Japan (Kamitaga, Atami City, Shizuoka Prefecture, Honshu Island, Japan). Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY 4.0
Laihunite
Laihunite is an IMA-recognized mineral species in the silicate class, with the chemical formula (Fe³⁺,Fe²⁺, )₂(SiO₄).
It crystallizes in the monoclinic crystal system (space group P2_1/b).
Key properties: Mohs hardness 5.5–6.5; specific gravity 3.967; Pale brown, blackish brown streak; Submetallic to metallic luster.
IMA symbol Lai, IMA status: approved, named in 1976.
Found in a Precambrian metamorphic iron deposit, probably derived by oxidation of fayalite (Little Lai-He Village, China).
It is found associated with Quartz, \hypersthene, " magnetite, \hornblende, " augite, plagioclase (Little Lai-He, China).
The name refers to the occurrence at Little Lai-He Village, China.