Proustite
Chile
.35 carats
© raregemhunter
Proustite forms beautiful prismatic transparent adamantine dark red crystals, but they become dull black and opaque on exposure to light, therefore they must be kept in darkness.
Proustite is a rare stone. It is cut into brilliant faceted stones, but they are too soft to be set in jewelry.
Proustite 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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Proustite Gemstones by Size
This table shows distribution of Proustite 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:.35 cts
Heaviest:12.27 cts
Average:6.40 cts
Total photos:3
Do you have a larger Proustite? Why not upload a photo?
| General Information | |||||||||||||||||||||
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| Chemical Formula |
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| Photos of natural/un-cut material from mindat.org | |||||||||||||||||||||
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| Physical Properties of Proustite | |||||||||||||||||||||
| Mohs Hardness | 2.5, Gemmological Tables (2004) More from other references | ||||||||||||||||||||
| Specific Gravity | 5.51 to 5.64, Gemmological Tables (2004) More from other references | ||||||||||||||||||||
| Tenacity | Brittle, Gemstones (2009) | ||||||||||||||||||||
| Cleavage Quality | Distinct, Gemstones (2009) | ||||||||||||||||||||
| Fracture | Uneven,Conchoidal, Gemstones (2009) | ||||||||||||||||||||
| Light Sensitivity | Often darkens with exposure to light, Gems, Sixth Edition (2006) | ||||||||||||||||||||
| Optical Properties of Proustite | |||||||||||||||||||||
| Refractive Index | 2.792 to 3.087, Gemmological Tables (2004) More from other references | ||||||||||||||||||||
| Optical Character | Uniaxial/-, Gemmological Tables (2004) More from other references | ||||||||||||||||||||
| Birefringence | 0.295, Gemmological Tables (2004) More from other references | ||||||||||||||||||||
| Pleochroism | Strong, Gemstones (2009) | ||||||||||||||||||||
| Dispersion | Weak, Gemstones (2009) | ||||||||||||||||||||
| Colour | |||||||||||||||||||||
| Colour (General) | Cinnabar to scarlet-red, Gemstones of the world (2001) More from other references | ||||||||||||||||||||
| Transparency | Opaque, Gemmological Tables (2004) Rarely transparentMore from other references | ||||||||||||||||||||
| Lustre | Adamantine, Gems, Sixth Edition (2006) More from other references | ||||||||||||||||||||
| Crystallography of Proustite | |||||||||||||||||||||
| Crystal System | Trigonal, Gemmological Tables (2004) More from other references | ||||||||||||||||||||
| Habit | Rhombohedral, prismatic, Gems, Sixth Edition (2006) More from other references | ||||||||||||||||||||
| Geological Environment | |||||||||||||||||||||
| Where found: | Proustite occurs as a late-forming mineral in hydrothermal deposits in the oxidized and enriched zone, with other silver minerals and sulphides., Gems, Sixth Edition (2006) | ||||||||||||||||||||
| Further Information | |||||||||||||||||||||
| Mineral information: | Proustite information at mindat.org | ||||||||||||||||||||
| Significant Gem Localities | |||||||||||||||||||||
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