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.

Hardness

4-4.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineraluncommonBastnäsite Group family

Bastnäsite-(Ce)

Also: Bastnaesite-(Ce)

Hardness: 4-4.5
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this bastnäsite-(ce)?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try 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.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Bastnäsite-(Ce) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Bastnäsite-(Ce) typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, reddish-brown, brown, colorless.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: tabular crystals, massive, granular.

Often confused with

Bastnäsite-(Ce) vs. its common look-alikes — and how to tell them apart in the field.

mineral

Calcite

Mohs 3

How to tell apart: Bastnäsite-(Ce) is noticeably harder (Mohs 4-4.5 vs. 3).

How to tell apart: Luster reads vitreous on Bastnäsite-(Ce) and resinous on Monazite.

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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: Yellow Reddish-brown Brown Colorless
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Hexagonal
Crystal habit: Tabular Crystals, Massive, Granular
Cleavage: Distinct On {1010}
Rarity: Uncommon
Uses: Collector, Rare-earth Element Ore
Host rock: Carbonatites, Rare-earth Pegmatites, Hydrothermal Veins
Typical price: $10-50 per specimen depending on size and crystal quality

Where rockhounds find bastnäsite-(ce)

Classic worldwide localities

Mountain Pass, California, USA
Bayan Obo, China
Kola Peninsula, Russia
Zagi Mountain, Pakistan

Field-hunting tip

Look in carbonatites, rare-earth pegmatites, hydrothermal veins country — that is the host setting where bastnäsite-(ce) typically forms. If you start seeing barite, fluorite, quartz in float, you are in the right ground. Field specimens usually show a tabular crystals, massive, granular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify bastnäsite-(ce)?+

Mohs hardness is 4-4.5. It typically shows a vitreous luster. The streak is white. Common colors include yellow, reddish-brown, brown, colorless.

Where is bastnäsite-(ce) found?+

Notable localities include Mountain Pass, California, USA; Bayan Obo, China; Kola Peninsula, Russia; Zagi Mountain, Pakistan.

How much is bastnäsite-(ce) worth?+

Typical asking prices fall in the range of $10-50 per specimen depending on size and crystal quality. Quality, size, and provenance can move individual specimens well outside that range.

Is bastnäsite-(ce) safe to handle?+

This mineral is radioactive. Bastnäsite-group minerals often contain minor amounts of thorium, making them slightly radioactive; keep in sealed containers and wash hands after handling. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like bastnäsite-(ce)?+

Bastnäsite-(Ce) is most often confused with Calcite, Dolomite, Monazite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with bastnäsite-(ce)?+

Bastnäsite-(Ce) commonly co-occurs with Barite, Fluorite, Quartz, Ankerite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does bastnäsite-(ce) form in?+

Bastnäsite-(Ce) typically forms in carbonatites, rare-earth pegmatites, hydrothermal veins. Working float back to the host body is the standard way to chase a fresh occurrence.

What is bastnäsite-(ce) used for?+

Bastnäsite-(Ce) is used in collector, rare-earth element ore.

Find bastnäsite-(ce) on the map

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