Imogolite
| Imogolite | |
|---|---|
| General | |
| Category | Clay mineral |
| Formula (repeating unit) | Al2SiO3(OH)4 |
| Strunz classification | 9.ED.20 |
| Crystal system | Tetragonal |
| Identification | |
| Color | White, blue, green, brown, black |
| Crystal habit | Conchoidal to earthy masses of microscopic threadlike particles and bundles of fine tubes, each about 20 Å in diameter |
| Mohs scale hardness | 2-3 |
| Luster | Vitreous, resinous, waxy |
| Diaphaneity | Transparent to translucent |
| Specific gravity | 2.7 |
| Optical properties | Isotropic |
| Refractive index | n=1.47-1.51 |
| References | [1][2][3] |
Imogolite is an aluminium silicate clay mineral with formula: Al2SiO3(OH)4. It occurs in soils formed from volcanic ash and was first described in 1962 for an occurrence in Uemura, Kumamoto prefecture, Kyushu Region, Japan.[1] Its name is derived from the Japanese imogo for the brownish yellow soil derived from volcanic ash. It occurs with allophane, quartz, cristobalite, gibbsite, vermiculite and limonite.[2]
Further reading
- Wada, Koji; Yoshinaga, Naganori (January–February 1969). "The structure of "Imogolite"" (PDF). The American Mineralogist 54: 50–71. Retrieved 13 March 2012.
- Gabriel, Jean-Christophe P.; Davidson, Patrick (2003). "Mineral Liquid Crystals from Self-Assembly of Anisotropic Nanosystems" (PDF). Top Curr Chem 226: 126–127.
|chapter=ignored (help) (Contains structure illustration)
References
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