Foitite
| Foitite | |
|---|---|
 | |
| General | |
| Category | Mineral |
| IMA symbol | Foi[1] |
| Crystal system | Trigonal |
| Identification | |
| Mohs scale hardness | 7 |
Foitite is a mineral in the tourmaline group,[2] it is a vacancy-dominant member of the group.[3] Foitite is in the 'vacancy' group, due to the absence of atoms in the X site.[2]
According to the Czech Geological Society, foitite is rare.[4] However foitite is quite common among low-temperature tourmalines[5] and it might be more common than previously thought.[6]
The color of the mineral is dark indigo with purple tints to bluish-black.[3]
Name
The mineral was named in 1993 by D. J. MacDonald, Frank C. Hawthorne, and Joel D.Grice after Franklin F. Foit, Jr.[5]
Chemistry
![[icon]](/wiki/File:Wiki_letter_w_cropped.svg){kind=small} | This section needs expansion. You can help by adding to it. (October 2021) |
It lacks alkalis like sodium.[7]
Occurrence
It occurs in quartz veins[8] and possibly occurs in granite pegmatites.[9]
Foitite has also been reported in Marquette County, Michigan.[6] It’s type locality is California.[5]
It has been reported in Wales and it’s predicted that a more widespread distribution of the mineral in Wales will be shown.[2]
References
- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ a b c "Mineral Database - Mineralogy of Wales". National Museum Wales. Retrieved 2021-10-12.
- ^ a b "Foitite gemstone information". www.gemdat.org. Retrieved 2021-10-28.
- ^ Journal of Geosciences. Czech Geological Society. 2010. p. 17.
- ^ a b c "Foitite". www.mindat.org. Retrieved 2021-10-12.
- ^ a b "Foitite" (PDF). The A. E. Seaman Mineral Museum. Retrieved 29 October 2021.
- ^ "Wisconsin Geological & Natural History Survey » Foitite". wgnhs.wisc.edu. Retrieved 2021-10-14.
- ^ "Tourmaline-Bearing Quartz Veins in the Baraboo Quartzite, Wisconsin: Occurrence and Significance of Foitite and "Oxy-Foitite"" (Document).
{{cite document}}: Cite document requires|publisher=(help); Unknown parameter|citeseerx=ignored (help) - ^ "Foitite" (PDF). Mineral Data Publishing. 2001. Retrieved 29 October 2021.