Vanadiocarpholite
(repeating unit)Mn+2V+3AlSi2O6(OH)4 IMA symbol Vcar[1] Strunz classification 9.DB.05 Crystal system Orthorhombic Crystal class Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m) Space group Ccca Unit cell a = 13.83 Å, b = 20.681 Å
c = 5.188 Å; Z = 8 Identification Color Pale-straw yellow, honey-yellow to brown Crystal habit Prismatic to acicular crystal clusters, vein fillings Cleavage Perfect on {010} Tenacity Flexible Luster Vitreous, silky Diaphaneity Transparent Optical properties Biaxial (+) Refractive index nα=1.684, nβ=1.691, nγ=1.7 Birefringence 0.0160 References [2][3]
H-M symbol: (2/m 2/m 2/m)
c = 5.188 Å; Z = 8
Vanadiocarpholite (Mn+2V+3AlSi2O6(OH)4) is straw yellow to brown silicate mineral. It crystallizes in the orthorhombic crystal system. It is the vanadium rich variety of carpholite (Mn+2Al2Si2O6(OH)4).
Discovery and occurrence
It was first described in 2005 for an occurrence in the Molinello Mine, Graveglia Valley, Genova Province, Liguria, Italy.[3] It occurs in chert in a manganese ore deposit as vein fillings in silicified wood.[2]
Chemical composition
It consists of:[2]
| Manganese | 15.56% | Mn | 20.09% | MnO |
| Aluminium | 7.64% | Al | 14.44% | Al2O3 |
| Vanadium | 14.43% | V | 21.23% | V2O3 |
| Silicon | 15.91% | Si | 34.04% | SiO2 |
| Hydrogen | 1.14% | H | 10.21% | H2O |
| Oxygen | 45.32% | O |
References
- ^ 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 Vanadiocarpholite data on Webmineral.com
- ^ a b Vanadiocarpholite on Mindat.org
- v
- t
- e
