mineral data
oregon sunstone mineral data
Mineral Species
- Feldspar - Labradorite
CRITICAL ANGLE & PAVILION ANGLE
- 42 degrees (best if cut at 43 degrees or higher on pavilion)
Variety
- Cuprian Oregon Sunstone
Specific Gravity
- 2.62 - 2.70 g/cm3
Crystal structure
- triclinic
Chemical Formula
- (Ca,Na)(Al,Si)2Si2O8
Hardness
- 6.5 - 7.0 Mohs
- Hardness similar or greater than Amethyst, Tanzanite, Garnet, Tourmaline, Peridot, Kunzite, Opal, etc.
Geologic Age and Occurrence
- 15.5 - 16.5 million years
- Oregon Sunstone is typically found in basaltic volcanic lava layers. Gems from PANA Mine & Sunstone Butte mine (previously one single mine) were created inside large magma chamber which cooled very slowly allowing for creation of extraordinary crystals both is size, clarity and range of colors.
Refractive Index
- 1.560 - 1.575
- Refractive Index similar to or higher than Emerald, Amethyst, Aquamarine, Andesine, Iolite, Citrine, Heliodor, etc.
RADIOACTIVITY
- Oregon Sunstone is not radioactive. This gemstone is safe to handle, store or wear in jewelry.
KNOWN TREATMENT
- Colored (red, orange, green, blue-teal, padparadscha, multicolor, etc…) Cuprian Oregon Sunstone is typically not treated because heat, radiation and other forms of treatment do not improve its color or clarity.
- Pale gold, straw and near colorless Oregon Sunstone and/or clear Oligoclase from Mexico, Mongolia and other locations is treated with a single-step or multi-step diffusion process turning near colorless or very pale stones into rich red, blue, green and even bi-color and dichroic stones. Such stones are sold as “Andesine”, “precious Sunstone” or simply as "Oregon Sunstone". Radiation is used to turn yellow-gold Labradorite Sunstone into pure orange. Some of these fakes being re-imported back into the USA, rest being typically marketed from Thailand, India and other countries. These fakes and misrepresented stones are identifiable by a trained gemologist based on chemical composition, color distribution and/or refractive index.