Uedaite-(Ce) is a rare member of the epidote group characterized by manganese dominance in the structure. It is typically found in skarn deposits as small, dark, prismatic crystals and is primarily sought after by advanced collectors of rare earth element minerals.
Is this uedaite-(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 uedaite-(ce) with a known reference. Uedaite-(Ce) sits at Mohs 5-6, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: gray.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: dark brown, black.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic.
Often confused with
Uedaite-(Ce) vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside uedaite-(ce)
Minerals reported to co-occur with uedaite-(ce). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- MnCeAl₂Fe³⁺(Si₂O₇)(SiO₄)O(OH)
- Mohs hardness
- 5-6
- Density
- 4.19 g/cm³
- Colors
- Streak
- Gray
- Luster
- Vitreous
- Transparency
- Translucent to opaque
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic
- Cleavage
- Poor {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- An accessory mineral in granite
Where rockhounds find uedaite-(ce)
Classic worldwide localities
- Shodoshima Island, Kagawa Prefecture, Japan
Field-hunting tip
Where it forms: An accessory mineral in granite. If you start seeing allanite-, monazite-, zircon in float, you are in the right ground. Typical habit: prismatic. Train your eye for that shape before scanning the outcrop.




