Sunstones form in molten lava and are found in volcanic vents that have erupted from volcanoes. When lava rock is weathered or broken, sunstone crystals are exposed. Crystals can be clear, pale yellow, pale pink, blood red, dark blue, and green. Some sunstone crystals will have streaks of different colors. This color variation is caused by different amounts of tiny copper crystals. More colored or darker fire opal rings contain more copper.
They are found all over the world, but quality stones large enough to be cut into jewelry are commonly found in Oregon. Crystals up to 3 inches in diameter have been found, but commonly range from 1/8 to 1 inch in length. Oregon is also the only place in the world where this gem material is found with copper, and in 1987 it was declared the official state gem of Oregon.
Rough natural opal stud earrings will range from approximately $400.00 to $500.00 per carat and with a good cut and polish can sell for over $1,000.00 per carat depending on size, color, clarity and cut. In 2006, the travel channel aired a show about the Spectrum Sunstone mines in the Cash and Treasures series. One of the sunstones found during filming, after it was cut and polished, weighed more than 10 carats and was sold to a couple in Oregon for $5,200.
Oregon sunstones are found only in the remote high desert in Lake and Harney counties, Oregon. The US Bureau of Land Management has set up a free public collection area in eastern Lake County, located near Plush Oregon. Until recently, this was the only known occurrence of gem-quality sunstones found in the United States.
The geology of Harney and Lake County is favorable for the discovery of additional deposits of these fine gems, and several additional mining claims have recently been established in the northern and southeastern areas of Harney County. These production premises are not available for public collection without the consent of the claim owners.
Sunstone Knoll southwest of Delta, Oregon is open to the public and is free. The best time to look for sunstones is right after rain. Sunstones will sparkle in the sunlight and can be found on the ground on the east side of the knoll. Opal gemstone typically range from 1/8 to 1 inch, but larger stones have also been found.
You will need to bring a small pick to use on the mine walls to uncover sunstones hidden between loose or broken rocks. Pliers or a screwdriver are used to pry gems out of broken rock. Loose dirt and broken rock are loaded with a shovel and five-gallon plastic bucket, which is then taken to the screening plant for further processing. The loosened dirt is collected on the screen and the screen is then shaken to remove small particles and sand.
