| Variscite | |
|---|---|
 | |
| General | |
| Category | Phosphate minerals |
| Formula (repeating unit) | AlPO4·2H2O |
| IMA symbol | Var[1] |
| Strunz classification | 8.CD.10 |
| Crystal system | Orthorhombic |
| Crystal class | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
| Space group | Pbca |
| Identification | |
| Color | Pale to emerald-green (pale green in transmitted light), green, blue green, yellow green, pale shades of brown or yellow, rarely red and colourless to white |
| Crystal habit | Encrustations and reniform masses |
| Cleavage | [010] perfect |
| Fracture | Conchoidal to splintery |
| Mohs scale hardness | 4.5 |
| Luster | Vitreous to waxy |
| Streak | White |
| Diaphaneity | Transparent to translucent |
| Specific gravity | 2.57 to 2.61 |
| Optical properties | Biaxial (−) |
| Refractive index | nα = 1.563 nβ = 1.588 nγ = 1.594 |
| Birefringence | δ = 0.031 |
| References | [2][3][4] |
Variscite is a hydrated aluminium phosphate mineral (AlPO4·2H2O). It is a relatively rare phosphate mineral. It is sometimes confused with turquoise; however, variscite is usually greener in color. The green color results from the presence of small amounts of trivalent chromium (Cr3+
).[5]
- ^ Warr, L. N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. Vol. 85, no. 3. Mineralogical Society of Great Britain and Ireland. pp. 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ "Variscite" (PDF). Handbook of Mineralogy. RRUFF Project.
- ^ Variscite, Mindat.org
- ^ Variscite Mineral Data, WebMineral.com
- ^ Cite error: The named reference
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