Bystrite
From Wikipedia, the free encyclopedia
| Bystrite | |
|---|---|
| General | |
| Category | Tectosilicate minerals |
| Group | Feldspathoid group, cancrinite group |
| Formula | (Na,K)7Ca(Si6Al6)O24S4.5•(H2O) |
| IMA symbol | Bys[1] |
| Strunz classification | 9.FB.05 |
| Dana classification | 76.02.05.02 |
| Crystal system | Trigonal |
| Crystal class | Ditrigonal pyramidal (3m) H-M symbol: (3m) |
| Space group | P31c |
| Identification | |
| Color | Yellow |
| Crystal habit | Tabular to irregular grains and inclusions |
| Cleavage | {1010} Good |
| Mohs scale hardness | 5 |
| Luster | Vitreous |
| Streak | light yellow |
| Diaphaneity | Transparent to translucent |
| Specific gravity | 2.43 |
| Optical properties | Uniaxial (+) |
| Refractive index | nω = 1.584 nε = 1.660 |
| Birefringence | δ = 0.076 |
| Pleochroism | Deep yellow to colorless |
| References | [2][3][4][5] |
Bystrite is a silicate mineral with the formula (Na,K)7Ca(Si6Al6)O24S4.5•(H2O), and a member of the cancrinite mineral group. It is a hexagonal crystal, with a 3m point group. The mineral may have been named after the Malaya Bystraya deposits in Russia, where it was found.[3]
Bystrite is a cancrinite mineral and exhibits similar physical properties, composition and structure as other cancrinites.
Bystrite has a structure that is shared with many of the minerals in the cancrinite group. It exhibits a hexagonal crystal structure with a 3m point group. Bystrite also has a P31c space group.[6] The structure of bystrite could not be easily found due to the mineral exhibiting a strong pseudotranslation, therefore, mineralogists made a model to find out the internal structure of the bystrite mineral, the idea was based on analyzing the tetrahedral frameworks of cancrinite minerals, and it did yield accurate results in predicting the structure of the mineral. Bolotina et al. (2004)[citation needed]