Achalaite
Appearance
Achalaite | |
---|---|
General | |
Category | Mineral |
Formula (repeating unit) | (Fe2+,Mn)(Ti,Fe3+,Ta)(Nb,Ta)2O8 |
IMA symbol | Ahl[1] |
Strunz classification | 4.D0. |
Crystal system | Monoclinic |
Unit cell | a = 9.422(4) [Å], b = 11.427(3) [Å] c = 5.120(1) [Å]; β = 90.12°; Z = 4[2] |
Identification | |
Color | Black |
Crystal habit | fibrous |
Mohs scale hardness | 5.5 |
Luster | metallic |
Streak | black |
Specific gravity | 6.285 |
Density | 6.285 g/cm3 |
Pleochroism | Non-pleochroic |
References | [2] |
Achalaite ((Fe2+, Mn)(Ti, Fe3+, Ta)(Nb, Ta)2O8) is a black mineral of the wodginite group, first discovered in 2013.[3]
It crystallizes in the monoclinic system and has a dark, metallic luster, a specific gravity of 6.285 and a Mohs hardness of 5.5.[4]
Achalaite occurs in the intermediate zone of topaz- and tantalite-bearing pegmatite.[4] Associated minerals include rutile, quartz and albite.[2]
Its name comes from the type locality: the Achala batholith in Córdoba, Argentina and the mineral has been approved by the IMA with the acronym 2013-103.[2]
References
[edit]Look up achalaite in Wiktionary, the free dictionary.
- ^ 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 c d "Achalaite". Mindat.org. Retrieved 8 March 2019.
- ^ "The New IMA List of Minerals – A Work in Progress – Updated: July 2016" (PDF). International Mineralogical Association COMMISSION ON NEW MINERALS, NOMENCLATURE AND CLASSIFICATION. Archived from the original (PDF) on 9 September 2016. Retrieved 8 March 2019.
- ^ a b "Achalaite Fe2+TiNb2O8" (PDF). Handbook of Mineralogy. Retrieved 8 March 2019.