Tistarite

Tistarite is an exceedingly rare mineral with the formula Ti₂O₃, thus being the natural analogue of titanium(III) oxide.[2][1] 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.[1][3][4] The only known terrestrial occurrence of tistarite was found during minerals exploration by Shefa Yamim Ltd. in the upper mantle beneath Mount Carmel, Israel.[5][6]

Tistarite
General
Category	Oxide minerals
Formula (repeating unit)	Ti2O3
Strunz classification	4.CB.05
Crystal system	Trigonal
Crystal class	Hexagonal scalenohedral (3m) H-M symbol: (3 2/m)
Space group	R3c
Identification
References	[1]

References

1. Mindat, Tistarite, http://www.mindat.org/min-38695.html
2. Ma, C., and Rossmann, G.R., 2009: Tistarite, Ti₂O₃, a new refractory mineral from the Allende meteorite. American Mineralogist 94(5-6), 841-844
3. Mindat, Kangite, http://www.mindat.org/min-42879.html
4. Mindat, Yttriaite-(Y), http://www.mindat.org/min-40471.html
5. W.L. Griffin, S.E.M. Gain, D.T. Adams, J-X. Huang, M. Saunders, V. Toledo, N.J. pearson, and S.Y. O'Reilly (2016-08-17), First terrestrial occurrence of tistarite (Ti₂O₃): Ultra-low oxygen fugacity in the upper mantle beneath Mount Carmel, Israel (PDF), Geological Society of America, doi:10.1130/G37910.1, archived (PDF) from the original on 2016-09-12, retrieved 2016-09-12 – via Shefa Yamim Ltd.CS1 maint: uses authors parameter (link)
6. J-Wire Staff (2016-02-21). "Australian university confirms Israeli rare mineral discovery". J-Wire. Archived from the original on 2016-02-22. Retrieved 2016-09-12.CS1 maint: uses authors parameter (link)