Sunstone is a member of the feldspar group. Both the orthoclase and the plagioclase feldspar species boast a sunstone variety. Other feldspar group gems include moonstone, non-phenomenal orthoclase, phenomenal and non-phenomenal labradorite, and amazonite. Sunstone from Oregon is gaining attention as a natural and untreated product of the United States.
Sunstone is a member of the feldspar group of minerals.
Sunstone can have a sparkly, metallic-looking luster caused by flat, reflective inclusions.
Oregon sunstone is a transparent feldspar with glittery copper inclusions.
Orthoclase - KAlSi3O8
Oligoclase and labradorite - solid solution between NaAlSi3O8 and CaAl2Si2O8
Yellow, green, red, red-brown, colorless
Orthoclase sunstone - 1.518 to 1.526
Oligoclase sunstone - 1.537 to 1.547
Labradorite sunstone - 1.559 to 1.568
Orthoclase - 0.005 to 0.008
Oligoclase and labradorite - 0.007 to 0.010
Orthoclase - 2.58
Oligoclase - 2.65
Labradorite - 2.70
- Mohs hardness: 6.0 – 7.2
There are a number of processes used to alter the color, apparent clarity, or improve the durability of gems.Learn More
Some gemstones have synthetic counterparts that have essentially the same chemical, physical, and optical properties, but are grown by man in a laboratory.Learn More
Any gem can be imitated—sometimes by manmade materials or by natural materials chosen by man to impersonate a particular gem.Learn More
Why We Love This Gemstone
Reflective inclusions in sunstone’s phenomenal varieties cause a distinct and lively glitter called aventurescence.
Oregon sunstone’s colors don’t result from treatment. The gem’s all natural and it’s mined in the United States.
Red-colored Oregon sunstone is often marketed to consumers as “spinel red.” Its vivid hue rivals spinel and even ruby.
The following factors combine to determine a sunstone’s value.
The most in-demand sunstone colors are deep red – like this gem – deep green, and intense bicolors.
Small inclusions provide a reddish or golden sheen; larger inclusions create glittering reflections.
Creative cuts and calibrated gems alike are designed to highlight the gem’s glowing colors.
Sunstone is available in a range of sizes, but large carved gems like this Oregon beauty are rare.
Sunstone Quality Factors: The Comprehensive Guide
Explore sources, gemological research, and the role of gems in history.
A Sunstone Odyssey,
Part 1: The Ponderosa
Ribbe, P. H