Brianite
Appearance
Brianite | |
---|---|
Small white microcrystals of brianite from the Dayton meteorite | |
General | |
Category | Phosphate minerals |
Formula (repeating unit) | Na2CaMg(PO4)2 |
IMA symbol | Bne[1] |
Strunz classification | 8.AC.30 |
Crystal system | Monoclinic |
Crystal class | Prismatic (2/m) (same H-M symbol) |
Space group | P21/a |
Unit cell | a = 13.36 Å, b = 5.23 Å, c = 9.13 Å, β = 91.2°; Z = 4 |
Identification | |
Color | Colorless |
Crystal habit | Anhedral grains with lamellar structure visible under polarized light |
Twinning | Polysynthetic on {100} |
Mohs scale hardness | 4-5 |
Luster | Vitreous |
Diaphaneity | Transparent |
Specific gravity | 3.0-3.1 |
Optical properties | biaxial (-) |
Refractive index | nα = 1.598, nβ = 1.605, nγ = 1.608 |
Birefringence | 0.010 |
2V angle | 63° to 65° |
Extinction | 2 to 3° from lamellae |
References | [2][3][4][5] |
Brianite is a phosphate mineral with the chemical formula Na2CaMg(PO4)2.[4] It was first identified in an iron meteorite.[3] This mineral is named after Brian Harold Mason (1917–2009), a pioneer in meteoritics.[3]
It was first reported from the Dayton meteorite in Montgomery County, Ohio in 1966.[3] It occurs in phosphate nodules within the meteorite. Associated minerals include: panethite, whitlockite, albite, enstatite, schreibersite, kamacite, taenite, graphite, sphalerite and troilite.[5]
See also
[edit]References
[edit]- ^ 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.
- ^ Mineralienatlas
- ^ a b c d Brianite mineral information and data on Mindat
- ^ a b Brianite data on Webmin
- ^ a b "Brianite data from the Handbook of Mineralogy" (PDF). Archived from the original (PDF) on 2015-09-24. Retrieved 2015-01-31.