Sunstone is a plagioclase feldspar variety known for its distinctive 'aventurescence', a glittering metallic sheen caused by internal reflections from copper or hematite inclusions. It typically occurs as transparent to translucent crystals in volcanic rocks or pegmatites and is prized by collectors for its warm, fiery colors and unique optical play.
Is this sunstone?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch sunstone with a known reference. Sunstone sits at Mohs 6-6.5 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Sunstone leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Sunstone typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: orange, red, gold, brown, colorless.
- 5Look at form & habitCrystal system: triclinic. Typical habit: tabular crystals.
Often confused with
Sunstone vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside sunstone
Minerals reported to co-occur with sunstone. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Na,Ca)(Si,Al)₄O₈
- Mohs hardness
- 6-6.5
- Density
- 2.62-2.67 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Triclinic
- Crystal habit
- Tabular Crystals
- Cleavage
- Perfect in Two Directions
- Rarity
- Uncommon
- Uses
- Gemstone, Lapidary, Collector
- Host rock
- Basaltic Lava Flows, Pegmatites
- Typical price
- $10-100 per carat for high-quality specimens
Where rockhounds find sunstone
10 mapped spotsClassic worldwide localities
- Oregon, USA
- Norway
- India
- Tanzania
- Canada
Field-hunting tip
Look in basaltic lava flows, pegmatites country — that is the host setting where sunstone typically forms. If you start seeing quartz, muscovite, biotite in float, you are in the right ground. Field specimens usually show a tabular crystals habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in New York, New Jersey, North Carolina — start trip planning there.
Common questions
How do you identify sunstone?+
Where is sunstone found?+
Can I find sunstone in the United States?+
How much is sunstone worth?+
What rocks look like sunstone?+
What minerals are found with sunstone?+
What kind of rock does sunstone form in?+
What is sunstone used for?+
Find sunstone on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
