Sunstone (Aventurine feldspar)
Oregon, USA
2.38 carats
© Mineral Classics
The name derives from sunstones believed to have been used for navigation in the Middle Ages.
Sunstone is the official gemstone of Oregon, USA.
Sunstone 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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Sunstone Gemstones by Size
This table shows distribution of Sunstone 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:1.69 cts
Heaviest:17.54 cts
Average:6.20 cts
Total photos:26
Do you have a larger Sunstone? Why not upload a photo?
| General Information | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| A variety or type of: | Feldspar | |||||||||||||
| Chemical Formula |
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| Physical Properties of Sunstone | ||||||||||||||
| Mohs Hardness | 6 to 6.5, Blue Chart Gem Identification (2010) | |||||||||||||
| Specific Gravity | 2.62 to 2.67, Blue Chart Gem Identification (2010) More from other references | |||||||||||||
| Tenacity | Brittle, Gemstones of the world (2001) | |||||||||||||
| Cleavage Quality | Perfect, Gemmological Tables (2004) | |||||||||||||
| Fracture | Splintery, Gemstones of the world (2001) | |||||||||||||
| Optical Properties of Sunstone | ||||||||||||||
| Refractive Index | 1.525 to 1.552, Blue Chart Gem Identification (2010) More from other references | |||||||||||||
| Optical Character | Biaxial/-, Blue Chart Gem Identification (2010) | |||||||||||||
| Birefringence | 0.007 to 0.010, Blue Chart Gem Identification (2010) More from other references | |||||||||||||
| Pleochroism | Weak or absent, Gemstones of the world (2001) | |||||||||||||
| Dispersion | None, Gemstones of the world (2001) | |||||||||||||
| Colour | ||||||||||||||
| Colour (General) | Reddish-brown, brownish-red, golden brown. Aventurescent, Gemmological Tables (2004) | |||||||||||||
| Transparency | Translucent,Opaque, Gemmological Tables (2004) | |||||||||||||
| Fluorescence & other light emissions | ||||||||||||||
| Fluorescence (General) | Dark brown-red, Gemstones of the world (2001) | |||||||||||||
| Crystallography of Sunstone | ||||||||||||||
| Crystal System | Triclinic, Blue Chart Gem Identification (2010) | |||||||||||||
| Habit | Rare, solid aggregates, Gemstones of the world (2001) | |||||||||||||
| Further Information | ||||||||||||||
| Mineral information: | Sunstone information at mindat.org | |||||||||||||
| Significant Gem Localities | ||||||||||||||
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