
Mexico
5.63 carats
© Rarestone.com
| General Information | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| A variety or type of: | Feldspar | |||||||||
| Chemical Formula |
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| Physical Properties of Bytownite | ||||||||||
| Mohs Hardness | 6 to 6.5, Blue Chart Gem Identification (2010) More from other references | |||||||||
| Specific Gravity | 2.72 to 2.75, Blue Chart Gem Identification (2010) More from other references | |||||||||
| Tenacity | Brittle, Gems, Sixth Edition (2006) | |||||||||
| Cleavage Quality | Perfect, Gemmological Tables (2004) More from other references | |||||||||
| Fracture | Uneven,Conchoidal, Gems, Sixth Edition (2006) | |||||||||
| Optical Properties of Bytownite | ||||||||||
| Refractive Index | 1.561 to 1.583, Blue Chart Gem Identification (2010) More from other references | |||||||||
| Optical Character | Biaxial/-, Blue Chart Gem Identification (2010) More from other references | |||||||||
| Birefringence | 0.007 to 0.011, Blue Chart Gem Identification (2010) More from other references | |||||||||
| Dispersion | Low (0.012), Gems, Sixth Edition (2006) | |||||||||
| Colour | ||||||||||
| Colour (General) | Yellowish, reddish-brown, labradorescent, Gemmological Tables (2004) More from other references | |||||||||
| Transparency | Transparent,Translucent, Gemmological Tables (2004) More from other references | |||||||||
| Lustre | Vitreous,Dull (Earthy), Gems, Sixth Edition (2006) Vitreous to dull | |||||||||
| Crystallography of Bytownite | ||||||||||
| Crystal System | Triclinic, Blue Chart Gem Identification (2010) More from other references | |||||||||
| Geological Environment | ||||||||||
| Where found: | It is usually found as compact masses and grains in gabbros, norites, allivalites and anorthosites. It also forms from sodic metasomatism of metamorphic rocks. Often it occurs as part of compositionally zoned feldspars., Gems, Sixth Edition (2006) | |||||||||
| Further Information | ||||||||||
| Mineral information: | Bytownite information at mindat.org | |||||||||