Lucasite-(Ce) is a rare rare-earth titanium hydroxide mineral primarily found in carbonatite deposits. It typically forms small, fragile, platy crystals that are often identified by their characteristic brownish-yellow color and perfect basal cleavage. Collectors usually seek out specimens from its type locality at the Mount Weld carbonatite in Western Australia.
Is this lucasite-(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 lucasite-(ce) with a known reference. Lucasite-(Ce) sits at Mohs 6-6.5, 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.
- 4Match the color rangeCompare against the expected color range: brown, dark brown, chocolate brown.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: striated, subhedral crystals.
Often confused with
Lucasite-(Ce) vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside lucasite-(ce)
Minerals reported to co-occur with lucasite-(ce). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CeTi₂O₅(OH)
- Mohs hardness
- 6-6.5
- Density
- 5.00 g/cm³
- Colors
- Streak
- White
- Luster
- Resinous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Striated, subhedral crystals
- Cleavage
- Good on {001}, may be a parting
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In heavy-media concentrates from non-sandy tuff in an olivine lamproite diatreme
Where rockhounds find lucasite-(ce)
Classic worldwide localities
- Argyle AK1 diamond mine, east Kimberley area, Western Australia
Field-hunting tip
Where it forms: In heavy-media concentrates from non-sandy tuff in an olivine lamproite diatreme. If you start seeing calcite, dolomite, talc in float, you are in the right ground. Typical habit: striated, subhedral crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify lucasite-(ce)?+
Where is lucasite-(ce) found?+
What rocks look like lucasite-(ce)?+
What minerals are found with lucasite-(ce)?+
What kind of rock does lucasite-(ce) form in?+
What is lucasite-(ce) used for?+
Find lucasite-(ce) on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
