Scapolite is a group of silicate minerals most commonly found in contact metamorphic rocks like skarn. Collectors should look for its characteristic tetragonal prismatic crystal habit and frequent bright fluorescence under UV light, which helps distinguish it from common feldspars.
Is this scapolite?
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 scapolite with a known reference. Scapolite sits at Mohs 6, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: colorless, white, gray, yellow, pink, violet, blue, pale brown.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: massive, prismatic.
Often confused with
Scapolite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside scapolite
Minerals reported to co-occur with scapolite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₄Al₃Si₉O₂₄Cl to Ca₄Al₆Si₆O₂₄(CO₃)
- Mohs hardness
- 6
- Density
- 2.56-2.77 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Tetragonal
- Crystal habit
- Massive, prismatic
- Cleavage
- Distinct on {100}; distinct on {110}
- Fluorescence
- Fluorescent
- Rarity
- Common
- Uses
- Collector, Gemstone, Lapidary
- Host rock
- metamorphic rocks like skarns, marbles, and gneisses
Where rockhounds find scapolite
3 mapped spotsClassic worldwide localities
- Otter Lake, Canada (type locality)
Field-hunting tip
Where it forms: metamorphic rocks like skarns, marbles, and gneisses. If you start seeing diopside, garnet, amphibole in float, you are in the right ground. Typical habit: massive, prismatic. Train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in New York, Massachusetts. Start trip planning there.
Common questions
How do you identify scapolite?+
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Can I find scapolite in the United States?+
What rocks look like scapolite?+
What minerals are found with scapolite?+
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Find scapolite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
