Chibaite
Appearance
Chibaite | |
---|---|
![]() White crystals of the rare silica-hydrocarbon minerals chibaite (IMA 2008-067) and bosoite (IMA 2014-023) from the type and only known locality worldwide for both species: Arakawa, Minamiboso City, Chiba Prefecture, Honshu Island, Japan. | |
General | |
Category | Mineral |
Formula (repeating unit) | SiO2•n(CH4, C2H6, C3H8, i-C4H10) (n ≤ 3/17) |
IMA symbol | Cib[1] |
Strunz classification | 4.DA |
Crystal system | Isometric |
Space group | F2/d3 |
Unit cell | a = 19.3742 V=7,272.29 Å3 |
Identification | |
Colour | white |
Mohs scale hardness | 7 |
Luster | Vitreous |
Specific gravity | 1.933 |
Optical properties | isotropic |
Refractive index | 1.470 |
Chibaite is a rare silicate mineral. It is a silica clathrate with formula SiO
2•n(CH
4,C
2H
6,C
3H
8,i-C
4H
10) (n = 3/17 (max)). The mineral is cubic (diploidal class, m3) and the silica hosts or traps various hydrocarbon molecules, such as methane, ethane, propane and isobutane.[2][3]
Chibaite was first described for specimens collected from Arakawa, Minamibōsō, Chiba Prefecture, Honshu Island, Japan. The mineral was approved by the IMA in 2009.[2][3]
References
- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ a b Chibaite on Mindat.org
- ^ a b The Discovery of Chibaite, Elements, June 2012, section: Japan Association of Mineralogical Sciences p. 230