| Vanadiocarpholite | |
| Category: | Silicate mineral |
| Formula: | Mn+2V+3AlSi2O6(OH)4 |
| Imasymbol: | Vcar[1] |
| Strunz: | 9.DB.05 |
| System: | Orthorhombic |
| Class: | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
| Symmetry: | Ccca |
| Unit Cell: | a = 13.83 Å, b = 20.681 Å c = 5.188 Å; Z = 8 |
| Color: | Pale-straw yellow, honey-yellow to brown |
| Habit: | Prismatic to acicular crystal clusters, vein fillings |
| Cleavage: | Perfect on |
| Tenacity: | Flexible |
| Luster: | Vitreous, silky |
| Diaphaneity: | Transparent |
| Opticalprop: | Biaxial (+) |
| Refractive: | nα=1.684, nβ=1.691, nγ=1.7 |
| Birefringence: | 0.0160 |
| References: | [2] [3] |
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).
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]
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 |