Alnaperbøeite-(Ce) is an extremely rare silicate mineral identified from alkaline complexes. It typically presents as small, brownish tabular crystals found embedded within nepheline syenites and related igneous formations.
Is this alnaperbøeite-(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 alnaperbøeite-(ce) with a known reference. Alnaperbøeite-(Ce) sits at Mohs 6-7, 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.
- 4Match the color rangeCompare against the expected color range: very pale green.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic to tabular crystals.
Often confused with
Alnaperbøeite-(Ce) vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Alnaperbøeite-(Ce) leaves white, Epidote leaves grayish white.
How to tell apart: Streak differs, so Alnaperbøeite-(Ce) leaves white, Allanite leaves gray; luster reads vitreous on Alnaperbøeite-(Ce) and submetallic on Allanite.
All properties
- Chemical formula
- (CaCe₂.₅Na₀.₅)Al₄(Si₂O₇)(SiO₄)₃O(OH)₂
- Mohs hardness
- 6-7
- Density
- 4.308 g/cm³
- Colors
- Very pale green
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic to tabular crystals
- Cleavage
- Good on {100}, imperfect on {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A late primary phase in REE-bearing quartz-microcline pegmatite
Where rockhounds find alnaperbøeite-(ce)
Classic worldwide localities
- Hundholmen, Stetind, and Nedre Eivollen pegmatites in the Tysfjord granite, Norway
Field-hunting tip
Where it forms: A late primary phase in REE-bearing quartz-microcline pegmatite. If you start seeing yttrian fluorite, törnebohmite-, allanite- in float, you are in the right ground. Typical habit: prismatic to tabular crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify alnaperbøeite-(ce)?+
Where is alnaperbøeite-(ce) found?+
What rocks look like alnaperbøeite-(ce)?+
What minerals are found with alnaperbøeite-(ce)?+
What kind of rock does alnaperbøeite-(ce) form in?+
What is alnaperbøeite-(ce) used for?+
Find alnaperbøeite-(ce) on the map
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