Bastnäsite-(Ce) is a primary ore of rare earth elements, often occurring as flat, hexagonal, honey-brown crystals. It is frequently found in carbonatite deposits where it may be associated with fluorite and barite. Collectors should check for high-quality, sharp crystals from the Mountain Pass locality or the Zagi Mountains.
Is this bastnäsite-(ce)?
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 bastnäsite-(ce) with a known reference. Bastnäsite-(Ce) sits at Mohs 4-4.5, 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: vitreous to greasy, pearly on basal partings.
- 4Match the color rangeCompare against the expected color range: yellow, reddish brown.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: massive, prismatic.
Often confused with
Bastnäsite-(Ce) vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside bastnäsite-(ce)
Minerals reported to co-occur with bastnäsite-(ce). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ce(CO₃)F
- Mohs hardness
- 4-4.5
- Density
- 4.9-5.2 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous to greasy, pearly on basal partings
- Transparency
- Transparent
- Crystal system
- Hexagonal
- Crystal habit
- Massive, prismatic
- Cleavage
- On {1010}, indistinct; {0001}, a parting, distinct to perfect
- Rarity
- Uncommon
- Uses
- Collector, Rare-earth element ore
- Host rock
- The most abundant RE-bearing mineral, typically hydrothermal, although primary igneous occurrences are known
Where rockhounds find bastnäsite-(ce)
Classic worldwide localities
- Sweden, from the Bastnäs mine, near Riddarhyttan, Västmanland
- Trimouns talc deposit, six km northeast of Luzenac, Ariège, France
- Shinwaro, Kunar Province, Afghanistan
- Zegi Mountain, Fata, Pakistan
- Andakatany, Ambatofangehana
Field-hunting tip
Where it forms: The most abundant RE-bearing mineral, typically hydrothermal, although primary igneous occurrences are known. If you start seeing allanite-, cerianite-, synchysite- in float, you are in the right ground. Typical habit: massive, prismatic. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify bastnäsite-(ce)?+
Where is bastnäsite-(ce) found?+
Is bastnäsite-(ce) safe to handle?+
What rocks look like bastnäsite-(ce)?+
What minerals are found with bastnäsite-(ce)?+
What kind of rock does bastnäsite-(ce) form in?+
What is bastnäsite-(ce) used for?+
Find bastnäsite-(ce) on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
