Hauyne
From Wikipedia, the free encyclopedia
| Hauyne | |
|---|---|
| Category | Mineral |
| Chemical formula | (Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2 |
| Identification | |
| Color | Blue, white, grey, ... |
| Crystal system | Isometric |
| Cleavage | Distinct/Good, Distinct on {110} |
| Fracture | Irregular/Uneven, Conchoidal |
| Mohs Scale hardness | 5 to 6 |
| Luster | Vitreous, Greasy |
| Refractive index | n = 1.494 - 1.509 |
| Specific gravity | 2.4 to 2.5 |
Hauyne, haüyne or hauynite is a tectosilicate mineral with sulfate and chloride with formula: (Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2. It is a feldspathoid and a member of the sodalite group. Hauyne crystallizes in the isometric system forming translucent, vitreous typically twinned crystals with highly variable color (blue, white, grey, yellow, green, pink). It has a Mohs hardness of 5 to 6 and a specific gravity of 2.4 to 2.5.
Hauyne was first described in 1807 from samples at Vesuvius Mount Somma, Italy. It was named for the French crystallographer, Rene Just Hauy (1743-1822). It occurs in silica deficient igneous rocks in a wide variety of locations.
