Pezzottaite (also transcriptions are pezzottaite , pedzottaya ; raspberry beryl) is a rare mineral, silicate of cesium , beryllium , aluminum and lithium with the chemical formula Cs (Be 2 Li) Al 2 Si 6 O 18 . Cesium analogue of beryl , in which one of the three beryllium atoms is replaced by lithium and cesium atoms. Unlike beryl, it crystallizes in the trigonal system, and not in the hexagonal.
| Pezzottaite | |
|---|---|
 | |
| Formula | Cs (Be 2 Li) Al 2 Si 6 O 18 |
| Physical properties | |
| Color | raspberry red, pink, orange red |
| Trait color | colorless turning into white |
| Shine | glass |
| Transparency | translucent, transparent |
| Hardness | 8 |
| Cleavage | imperfect (001) |
| Kink | uneven, conch |
| Density | 2.97 g / cm³ |
| Syngonia | trigonal |
| Refractive index | 1,6 |
Named after Italian geologist and mineralogist Federico Pezzotta from the Civic Museum, Milan, Italy. Recognized by the International Mineralogical Association in 2003.
Pezzottaite is painted in various shades of red. Transparent or translucent.
Hardness 8 on the Mohs scale , density 2.97 g / cm³.
Transparent defect-free crystals lend themselves well to faceting . Used as a gem in jewelry.
Loses color when heated to 450 ° C for two hours.
Deposits
It was found in the pegmatites of southern Madagascar , as well as in Afghanistan.
Links
- Pezzottaite Description, photographs.
- All about beryl - varieties of beryl, deposits and unique finds.
- Mineralienatlas