Oregon Sunstone is a gemstone that deserves wider recognition. It is a type of plagioclase feldspar colored by copper. While the natural color of the feldspar is a golden yellow, the copper causes colors ranging from reds to greens and teal blues. In addition to the coloration, larger flakes of copper can cause an aventurine effect, reflecting the light like pieces of copper-colored glitter. This effect is referred to as schiller. While plagioclase feldspar is found in other locations in the world and can occasionally have a schiller effect, only the sunstone from Oregon contains copper, making it a unique and rare gemstone. With a hardness of 6-7 and a RI that ranges from 1.56 to 1.57, it cuts beautiful stones that are durable and have excellent brilliance and flash.
There are no named varieties or species of Oregon Sunstone.
Where is it found
Oregon Sunstone is limited to its namesake–the state of Oregon in the United States. To date it has only been found in two small areas of Oregon, one near Plush in Lake County and the other in nearby Harney County. Both are found in ancient lava flaws.
Oregon Sunstone is all-natural and no treatments have been reported. However, in the 2000’s there was a flood of “red sunstone” in the market that turned out to be artificially created by diffusing yellow to colorless andesine feldspar with copper to mimic the beautiful yet rare natural reds. After extensive testing, it was determined that this material was all manmade. While this is not a problem in and of itself, unfortunately it was not disclosed, and the material was being sold as natural.
Use in jewelry
Oregon sunstone is slowly gaining in popularity. It is well-suited to use in jewelry due to its hardness–at 6-7 on the Mohs scale, its similar to Tourmaline and Beryl. It can often be found in fairly large sizes, and is still very reasonably priced, although the finest reds and teals can become quite expensive due to their rarity.
Buy Oregon Sunstone
You can look at my current inventory of loose gemstones online here: http://www.earthstreasury.com/product-category/gemstones/oregon-sunstone/
Here’s a link to a number of articles and media resources about Oregon Sunstone on the GIA website: