Sonolite ore exhibited at Mining Museum of Akita University — Photo: 掬茶 · CC BY-SA 4.0
Sonolite
A manganese silicate of the humite group discovered in 1960 at Japan's Sono mine.
Intro adapted from Wikipedia (CC BY-SA).
Sonolite is an IMA-recognized mineral species in the silicate class, with the chemical formula Mn²⁺₉(SiO₄)₄(OH)₂.
It crystallizes in the monoclinic crystal system (space group P2_1/b). It is a member of the Humite structural group.
Key properties: Mohs hardness 5.5; specific gravity 3.82–4; Dull to vitreous luster; refractive index 1.777; optically biaxial.
IMA symbol Snl, IMA status: approved, named in 1963.
Found in metamorphosed manganese-rich deposits.
It is found associated with Rhodochrosite, galaxite, pyrochroite (Japan); franklinite, willemite, zincite, manganosite, chlorite, calcite, tephroite (Franklin, New Jersey, USA).
The name refers to the Sono mine, Japan, where it was originally found.