Doyleite
| Doyleite | |
|---|---|
| General | |
| Category | Minerals |
| Formula | Al(OH)3 |
| IMA symbol | Doy |
| Strunz classification | 4.FE.10 |
| Dana classification | 6.3.4.1 |
| Crystal system | Triclinic |
| Space group | P1 or P1 |
| Unit cell | 104.37 |
| Identification | |
| Formula mass | 78 |
| Color | White, creamy-white, bluish-white |
| Cleavage | Perfect on {010} Distinct on {100} |
| Mohs scale hardness | 2.5 - 3 |
| Luster | Vitreous |
| Streak | White |
| Optical properties | Biaxial (+) |
| Refractive index | nα = 1.545 nβ = 1.553 nγ = 1.566 |
| Birefringence | 0.021 |
| 2V angle | Measured: 77° Calculated: 78° |
| Dispersion | None |
Doyleite is a rare aluminum trihydroxide mineral named in honor of its discoverer, the Canadian physician Earl Joseph (Jess) Doyle. It was first definitively described in 1985 (although a partial description was published in 1979) and it is approved by the IMA. It was described from Mont Saint-Hilaire, where it is extremely rare.