| Agrellite | |
|---|---|
) Agrellite showing fluorescence in ultraviolet light | |
| General | |
| Category | Inosilicates |
| Formula (repeating unit) | NaCa2Si4O10F |
| Strunz classification | 9.DH.75 |
| Crystal system | Triclinic |
| Crystal class | Pinacoidal (1) (same H-M symbol) |
| Space group | P1 |
| Identification | |
| Color | White, grayish-white, greenish-white |
| Crystal habit | Lath - shaped like a small, thin plaster lath, rectangular in shape |
| Cleavage | perfect [110] |
| Mohs scale hardness | 5.5 |
| Luster | pearly |
| Streak | white |
| Diaphaneity | translucent |
| Specific gravity | 2.88 |
| Optical properties | biaxial |
| Refractive index | nα = 1.567 nβ = 1.579 nγ = 1.581 |
| Birefringence | δ = 0.014 |
| References | [1][2] |
Agrellite (NaCa2Si4O10F) is a mineral found in Quebec, Canada and a few other locations. Agrellite displays pink fluorescence under both shortwave and longwave ultraviolet light.[3] It is named in honour of Stuart Olof Agrell (1913–1996).[4]
References
- ^ http://www.mindat.org/min-57.html Mindat
- ^ http://www.webmineral.com/data/Agrellite.shtml Webmineral
- ^ Handbook of Mineralogy
- ^ first reported in the Canadian Mineralogist (1976), vol. 14, pp. 120-126