Oregon Sunstone Identification Guide
Identify Oregon sunstone, a copper-bearing labradorite feldspar with aventurescent schiller and a unique green-to-red color range.
Read the full Oregon Sunstone encyclopedia entry →
What Oregon Sunstone Looks Like
Oregon sunstone is a gem-quality plagioclase feldspar (labradorite composition) colored by tiny crystalline copper inclusions. It ranges from colorless and pale yellow to peach, salmon, pink, red, and rare blue-green, often with a metallic copper shimmer called schiller or aventurescence. Unlike most sunstone, its color and sparkle come from elemental copper, and the finest stones can be strongly bicolored or color-zoned.
- Color: colorless, yellow, peach, salmon, pink, red, green, teal
- Luster: vitreous; copper schiller gives metallic glints
- Transparency: transparent to translucent
- Form: broken crystal fragments and tabular cleavage pieces; faceted gems
Step-by-Step Field ID Checklist
- Tilt for copper schiller. Reddish-gold metallic sparkles that flash from inside as you rotate it are the signature.
- Look for cleavage planes. Two cleavage directions at near 90 degrees identify feldspar.
- Check color zoning. Natural Oregon sunstone often shows uneven color and bicolor zones.
- Test hardness. It scratches glass (about 6-6.5).
- Examine inclusions. Platy copper crystals aligned in layers appear under magnification.
Key Diagnostic Tests
- Hardness: Mohs 6-6.5.
- Streak: white.
- Cleavage: two good cleavages meeting near 90 degrees (feldspar).
- Density: about 2.65-2.70 g/cm3.
- Acid: no reaction.
- Inclusions: native copper platelets, distinguishing it from hematite-included sunstone.
Common Look-Alikes
- Indian/Tanzanian sunstone (oligoclase): schiller comes from hematite/goethite platelets (more orange-red metallic glitter), and lacks Oregon's copper-driven green and red body colors.
- Andesine (treated): copper-diffused feldspar marketed similarly; gemological testing distinguishes natural Oregon copper coloration.
- Citrine/peach quartz: no feldspar cleavage, no schiller, hexagonal habit, hardness 7.
- Sunstone glass (goldstone): man-made, packed with uniform copper flakes and round bubbles, no cleavage.
Where It Is Found
Oregon sunstone is found only in Oregon, USA, chiefly in Lake and Harney Counties (Plush/Ponderosa areas), weathered out of basaltic lava flows. It is Oregon's official state gemstone and one of the only natural copper-colored feldspars.
Frequently asked questions
How can you tell if Oregon sunstone is real?
Look for feldspar cleavage in two near-90-degree directions, hardness 6-6.5, and reddish-gold copper schiller from platy copper inclusions. Natural color zoning and green or red hues from copper support a genuine Oregon origin.
What is the difference between Oregon sunstone and Indian sunstone?
Oregon sunstone is labradorite colored by native copper, giving green and red body colors. Indian and Tanzanian sunstone is oligoclase with hematite platelets, producing orange-red glitter but not copper-based green or red coloring.
Is Oregon sunstone treated or natural?
Genuine Oregon sunstone is naturally colored by copper. Be cautious of copper-diffused andesine sold similarly; reputable Oregon sunstone is untreated, and gem labs can confirm natural copper coloration.
What does Oregon sunstone look like?
It looks like a transparent-to-translucent feldspar in peach, red, green, or colorless tones with sparkling reddish-gold copper schiller and often bicolor zoning.
Oregon Sunstone identified by the community
Recent Oregon Sunstone specimens identified with Rock Identifier.
