Opal
Opal
Item-No.: LM66 Price: 59.00 EUR
Herĺany, Košice Region, Slovakia
Opal
Item-No.: LM71 Price: 16.00 EUR
Borovina, Třebíč, Vsočina Region, Moravia, Czech Republic
Opal
Item-No.: LM87 Price: 28.00 EUR
Řípov, Třebíč, Vysočina Region, Moravia, Czech Republic
Opal
Item-No.: LM89 Price: 20.00 EUR
Řípov, Třebíč, Vysočina Region, Moravia, Czech Republic
Opal
Item-No.: LM91 Price: 22.00 EUR
Řípov, Třebíč, Vysočina Region, Moravia, Czech Republic
Opal
Item-No.: LM105 Price: 26.00 EUR
Nová Ves, Oslavany, South Moravia Region, Moravia, Czech Republic
Opal
Item-No.: LM124 Price: 13.00 EUR
Bohouškovice, Křemže, Český Krumlov, Bohemia, Czech Republic
| Synonyms: | Gel-Cristobalite, Gel-Pristobalite, Hemiopal, Invisible Quartz, Iridot, Lechosos, Neslite, Nevada Opal, Paederos, Potch, Rumanite, Semiopal, Vidrite, Virgin Valley Opal, White Cliffs Opal |
| Classification: | Oxides, Hydroxides |
| Chemical formula: | SiO2·nH2O |
| Crystal system: | Amorphose |
| Density (g/cm3): | 1,9 - 2,3 measured |
| Tenacity: | Brittle |
| Cleavage: | None observed |
| Fracture: | Irregular/Uneven, Splintery, Conchoidal |
| Hardness (Mohs): | 5,5 - 6,5 |
| Colour: | Colourless, white, yellow, red, orange, green, brown, black, blue |
| Lustre: | Vitreous, Waxy, Greasy, Dull |
| Streak: | White |
| Application: | Gemstone |