Tistarite | |
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General | |
Category | Oxide minerals |
Formula (repeating unit) | Ti2O3 |
IMA symbol | Tta[1] |
Strunz classification | 4.CB.05 |
Crystal system | Trigonal |
Crystal class | Hexagonal scalenohedral (3m) H-M symbol: (3 2/m) |
Space group | R3c |
Identification | |
References | [2] |
Tistarite is an exceedingly rare mineral with the formula Ti2O3, thus being the natural analogue of titanium(III) oxide.[4][2] In terms of chemistry it is the titanium-analogue of hematite, corundum, eskolaite, and karelianite. Other minerals with the general formula A2O3 are arsenolite, avicennite, claudetite, bismite, bixbyite, kangite, sphaerobismoite, yttriaite-(Y) and valentinite. Tistarite and grossmanite – both found in the famous Allende meteorite (so is kangite) – are the only currently known minerals with trivalent titanium. Titanium in minerals is almost exclusively tetravalent.[2][5][6] The only known terrestrial occurrence of tistarite was found during minerals exploration by Shefa Yamim Ltd. in the upper mantle beneath Mount Carmel, Israel.[3][7]