Hellandite-(Ce) is a rare borosilicate mineral typically found in complex granite pegmatites. It usually forms as brown to reddish-brown prismatic crystals and is highly valued by collectors due to its association with radioactive rare earth minerals.
Is this hellandite-(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 hellandite-(ce) with a known reference. Hellandite-(Ce) sits at Mohs 5.5 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Hellandite-(Ce) leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Hellandite-(Ce) typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: brown, yellowish-brown, reddish-brown.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic crystals.
Often confused with
Hellandite-(Ce) vs. its common look-alikes — and how to tell them apart in the field.

How to tell apart: Streak differs — Hellandite-(Ce) leaves white, Allanite leaves gray; luster reads vitreous on Hellandite-(Ce) and submetallic on Allanite.

How to tell apart: Gadolinite-(Y) is the harder of the two (Mohs 6.5-7 vs. 5.5).
Often found alongside hellandite-(ce)
Minerals reported to co-occur with hellandite-(ce). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Ca,Ce)₅Al□(B₄Si₄O₂₀)(OH,O)₂
- Mohs hardness
- 5.5
- Density
- 3.73 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic Crystals
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Granite Pegmatites
- Typical price
- $50-300 per specimen
Where rockhounds find hellandite-(ce)
Classic worldwide localities
- Kragerø, Norway
- Hitterø, Norway
- Tvedestrand, Norway
- Bancroft, Ontario, Canada
Field-hunting tip
Look in granite pegmatites country — that is the host setting where hellandite-(ce) typically forms. If you start seeing euxenite, fergusonite, zircon in float, you are in the right ground. Field specimens usually show a prismatic crystals habit, so train your eye for that shape before scanning the outcrop.



