Titanoholtite
Titanoholtite | |
---|---|
General | |
Category | Silicate mineral |
Formula (repeating unit) | (Ti0.75[]0.25)Al6BSi3O18 |
Crystal system | Orthorhombic |
Crystal class |
Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
Space group | Pbcm |
Unit cell |
a = 47.00 Å, b = 11.83 Å c = 20.24 Å |
Identification | |
References | [1][2] |
Titanoholtite is an extremely rare mineral with the formula (Ti0.75[]0.25)Al6BSi3O18. It is titanium-rich member of dumortierite supergroup, and titanium-analogue of holtite of the holtite group. It is one of three quite recently found minerals of this group, the other two being nioboholtite and szklaryite, all coming from the Szklary village near Ząbkowice Śląskie in Poland. They occur in a unique pegmatite of probable anatectic origin.[1][2]
Association
Titanoholtite is closely associated with holtite and nioboholtite; its further association is very rich (see szklaryite).[1]
Notes on chemistry
Impurities in titanoholtite are mainly antimony and arsenic, with trace niobium, tantalum, titanium, and iron.[1]
References
- 1 2 3 4 Pieczka, A.; Evans, R. J.; Grew, E. S.; Groat, L. A.; Ma, C.; Rossman, G. R. (2013). "The dumortierite supergroup. II. Three new minerals from the Szklary pegmatite, SW Poland: Nioboholtite, (Nb0.6〈0.4)Al6BSi3O18, titanoholtite, (Ti0.75〈0.25)Al6BSi3O18, and szklaryite, 〈Al6BAs3+3O15". Mineralogical Magazine. 77 (6): 2841. doi:10.1180/minmag.2013.077.6.10.
- 1 2 "Titanoholtite: Titanoholtite mineral information and data". Mindat.org. Retrieved 2016-03-03.
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