Uvite is a calcium-rich member of the tourmaline group, typically forming short, stout prismatic crystals in metamorphosed carbonate rocks. Collectors look for its distinctive trigonal cross-section and its tendency to be associated with contact-metamorphic minerals like diopside and calcite.
Is this uvite?
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 uvite with a known reference. Uvite sits at Mohs 7.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white, light green, light brown.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous to resinous.
- 4Match the color rangeCompare against the expected color range: brown, green, yellow, black, colorless, yellowish brown, blackish brown, bluish black.
- 5Look at form & habitCrystal system: trigonal. Typical habit: prismatic, striated.
Often confused with
Uvite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside uvite
Minerals reported to co-occur with uvite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CaMg₃(Al₅Mg)(Si₆O₁₈)(BO₃)₃(OH)₃OH
- Mohs hardness
- 7.5
- Density
- 2.97-3.14 g/cm³
- Streak
- White, light green, light brown
- Luster
- Vitreous to resinous
- Transparency
- Semitransparent
- Crystal system
- Trigonal
- Crystal habit
- Prismatic, striated
- Cleavage
- Indistinct on {1011}
- Fluorescence
- Yellow under SW UV
- Rarity
- Uncommon
- Uses
- Collector, Gemstone, Lapidary
- Host rock
- Typically in calcium-rich rocks subjected to contact metamorphism and metasomatic processes which added boron
Where rockhounds find uvite
1 mapped spotsClassic worldwide localities
- Franklin and Hamburg, Sussex Co., New Jersey, USA
- Gouverneur, Pierrepont, Dekalb, in St. Lawrence Co., and at Horicon, Warren Co., New York, USA
- East Hampton, Middlesex Co., Connecticut, USA
- Uva Province, Sri Lanka
- Sagaing district, Myanmar (Burma)
- Brumado, Bahia, Brazil
Field-hunting tip
Where it forms: Typically in calcium-rich rocks subjected to contact metamorphism and metasomatic processes which added boron. If you start seeing calcite, dolomite, tremolite in float, you are in the right ground. Typical habit: prismatic, striated. Train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in New York. Start trip planning there.
Common questions
How do you identify uvite?+
Where is uvite found?+
Can I find uvite in the United States?+
What rocks look like uvite?+
What minerals are found with uvite?+
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What is uvite used for?+
Find uvite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
