Ardennite-(V)
Mn2+4(AlMg)Al4(Si5V)O22(OH)6 [CNMNC approved formula]
Named as the vanadium analogue of ardennite-(As).
| IMA status : | Approved Species 2005 (IMA2005-037) |
| CLASSIFICATION | |
| Dana (8th edition) : |
58.03.01.03 (This Dana# Added) |
| (58) Sorosilicate Insular, Mixed, Single, and Larger Tetrahedral Groups | |
| (58.03) with insular single and triple groups (n=1,3) | |
| (58.03.01) Ardennite group | |
| Nickel-Strunz (10th edition) : |
09.BJ.40 |
| (09) Silicates | |
| (09.B) Sorosilicates (dimer) structures | |
| (09.BJ) Sorosilicates with Si3O10, Si4O11, etc. anions; cations in octahedral [6] and greater coordination | |
| Crystal system: | Orthorhombic System |
| Point group (H-M): | mmm (or 2/m 2/m 2/m) — dipyramidal |
| Unit cell: | a = 8.76Å, b = 5.838Å, c = 18.56Å |
| Crystal Habit: | accicular; tabular |
| Color: | Yellow |
| Diaphaneity: | Transparent |
| Luster: | Vitreous |
| Hardness (Mohs): | 6 - 7 |
| Measured Density: | 3.55 g/cm3 |
| Tenacity: | Brittle |
| Fracture: | Subconchoidal to uneven |
| Streak: | White |
| Geologic Setting: | Found in a specimen of piemontite-bearing mica schist. |
Ardennite-(V) crystals (yellow) with piemontite.Origin: Feilongo, Sparone, Orco Valley, Torino Province, Piedmont, Italy.
Image size: 5mm
Photo and owner: © Giovanni Fraccaro