Colemanite
Billie Mine (Billie group; Ryan Mine; Billie I Mine; Billie II Mine), Ryan, Furnace Creek Mining District (Furnace Creek Borate Mining District), Inyo County, California, USA
0.87 carats
© Rarestone.com
Colemanite has variable crystal habits: short prismatic crystals, stubby and bead-like equant crystals, flattened crystals, that appear bladed with terminations.
Colemanite is highly sensitive to heat.
Colemanite Gemstones by Colour
This table shows the variety of hues this gemstone can be found in. Click on a photo for more information.
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Colemanite Gemstones by Size
This table shows distribution of Colemanite gemstone sizes that are listed on this site. This can give a good indication as to the general availability of this gemstone in different sizes.
Contributed photos
Lightest:0.87 cts
Heaviest:9.33 cts
Average:4.08 cts
Total photos:3
Do you have a larger Colemanite? Why not upload a photo?
| General Information | ||||||||||||||||||
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| Chemical Formula |
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| Physical Properties of Colemanite | ||||||||||||||||||
| Mohs Hardness | 4.5, Gemmological Tables (2004) More from other references | |||||||||||||||||
| Specific Gravity | 2.40 to 2.42, Gemmological Tables (2004) More from other references | |||||||||||||||||
| Tenacity | Brittle, Gems, Sixth Edition (2006) | |||||||||||||||||
| Cleavage Quality | Perfect, Gemmological Tables (2004) More from other references | |||||||||||||||||
| Fracture | Uneven, Gemstones (2009) | |||||||||||||||||
| Heat Sensitivity | Highly sensitive, Gemstones (2009) | |||||||||||||||||
| Optical Properties of Colemanite | ||||||||||||||||||
| Refractive Index | 1.584 to 1.615, Gemmological Tables (2004) More from other references | |||||||||||||||||
| Optical Character | Biaxial/+, Gemmological Tables (2004) More from other references | |||||||||||||||||
| Birefringence | 0.028 to 0.030, Gemmological Tables (2004) More from other references | |||||||||||||||||
| Pleochroism | Nil, Gemstones (2009) | |||||||||||||||||
| Dispersion | Relatively weak, Gemstones (2009) | |||||||||||||||||
| Colour | ||||||||||||||||||
| Colour (General) | Colourless, gray-white, Gemstones of the world (2001) More from other references | |||||||||||||||||
| Transparency | Transparent,Translucent, Gemmological Tables (2004) More from other references | |||||||||||||||||
| Lustre | Vitreous, Gemstones (2009) | |||||||||||||||||
| Fluorescence & other light emissions | ||||||||||||||||||
| Fluorescence (General) | Commonly white or green, Gemmological Tables (2004) More from other references | |||||||||||||||||
| Crystallography of Colemanite | ||||||||||||||||||
| Crystal System | Monoclinic, Gemmological Tables (2004) More from other references | |||||||||||||||||
| Habit | Equant to short-prismatic crystals, Gems, Sixth Edition (2006) More from other references | |||||||||||||||||
| Geological Environment | ||||||||||||||||||
| Where found: | Colemanite is a common constituent of borate deposits formed in sodium- and carbonate-poor lake environments., Gems, Sixth Edition (2006) | |||||||||||||||||
| Further Information | ||||||||||||||||||
| Mineral information: | Colemanite information at mindat.org | |||||||||||||||||