Cheralite is a rare phosphate mineral in the monazite group that is notable for its significant thorium content. It is typically found as a component of heavy mineral sands or within granitic pegmatites, often appearing as yellowish to brownish grains. Due to its radioactivity, collectors should handle it with proper precautions and store it in a way that limits radiation exposure.
Is this cheralite?
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 cheralite with a known reference. Cheralite sits at Mohs 5, 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: resinous or greasy to vitreous.
- 4Match the color rangeCompare against the expected color range: pale, dark green, honey-, yellow-brown.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic crystals, granular, massive.
Often confused with
Cheralite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside cheralite
Minerals reported to co-occur with cheralite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CaTh(PO₄)₂
- Mohs hardness
- 5
- Density
- 5.28 g/cm³
- Colors
- Streak
- White
- Luster
- Resinous or greasy to vitreous
- Transparency
- Semitransparent
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic crystals, granular, massive
- Cleavage
- {010} distinct; {100} difficult; {001} a poor parting
- Rarity
- Rare
- Uses
- Collector, Scientific research
- Host rock
- Disseminated in a kaolinized pegmatite dike and surrounding kaolinized granite gneiss; alluvial (Kuttankuli, India); in a carbonatite (Mt. Weld, Western Australia)
Where rockhounds find cheralite
Classic worldwide localities
- Binghampton, Broome Co., New York, and in the Uranium King mine, Encampment, Carbon Co., Wyoming, USA
- Kuttankuli (Kuttakuzhi), about 42 km east-southeast of Trivandrum, Kerala State, India
- Ratnapura, Sri Lanka
- Mt. Weld carbonatite, 35 km south of Laverton, Western Australia
Field-hunting tip
Where it forms: Disseminated in a kaolinized pegmatite dike and surrounding kaolinized granite gneiss; alluvial (Kuttankuli, India); in a carbonatite (Mt. Weld, Western Australia). If you start seeing tourmaline, chrysoberyl, zircon in float, you are in the right ground. Typical habit: prismatic crystals, granular, massive. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify cheralite?+
Where is cheralite found?+
Is cheralite safe to handle?+
What rocks look like cheralite?+
What minerals are found with cheralite?+
What kind of rock does cheralite form in?+
What is cheralite used for?+
Find cheralite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
