| Otwayite | |
|---|---|
 Otwayite from the type locality in Otway Nickel deposit | |
| General | |
| Category | Carbonate mineral |
| Formula (repeating unit) | Ni2CO3(OH)2 |
| IMA symbol | Otw[1] |
| Strunz classification | 5.DA.15 |
| Crystal system | Orthorhombic Unknown space group |
| Unit cell | a = 10.18, b = 27.4, c = 3.22 [Å]; Z = 8 |
| Identification | |
| Color | Bright green |
| Crystal habit | Sprays of Fibrous bundles oriented perpendicular to veinlet walls; spherules and claylike coatings |
| Mohs scale hardness | 4 |
| Luster | Silky to waxy |
| Diaphaneity | Opaque to translucent |
| Specific gravity | 3.41 |
| Optical properties | Biaxial |
| Refractive index | nα = 1.650 nγ = 1.720 |
| Birefringence | δ = 0.070 |
| Pleochroism | Weak |
| Dispersion | Very strong |
| References | [2][3] |
Otwayite, Ni2CO3(OH)2, is a hydrated nickel carbonate mineral. Otwayite is green, with a hardness of 4, a specific gravity of 3.4, and crystallises in the orthorhombic system.
- ^ 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.
- ^ Mindat.org
- ^ Handbook of Mineralogy