Kalifersite is a very rare silicate mineral typically found in the vugs of alkaline pegmatites. Collectors look for its delicate, needle-like acicular crystals which often form radiating sprays within small cavities.
Is this kalifersite?
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 kalifersite with a known reference. Kalifersite sits at Mohs 2, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Kalifersite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Kalifersite typically shows a pearly luster.
- 4Match the color rangeCompare against the expected color range: white, colorless.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: fibrous, acicular, radiating clusters.
Often confused with
Kalifersite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside kalifersite
Minerals reported to co-occur with kalifersite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (K,Na,Ca)₃Si₈(O,OH)₂₄·nH₂O
- Mohs hardness
- 2
- Density
- 2.12 g/cm³
- Streak
- White
- Luster
- Pearly
- Transparency
- Translucent
- Crystal system
- Orthorhombic
- Crystal habit
- Fibrous, Acicular, Radiating Clusters
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Alkaline Igneous Rocks
- Typical price
- $50-300 per specimen
Where rockhounds find kalifersite
Classic worldwide localities
- Mont Saint-Hilaire, Quebec, Canada
- Khibiny Massif, Russia
- Langesundsfjord, Norway
Field-hunting tip
Look in alkaline igneous rocks country, the host setting where kalifersite typically forms. If you start seeing aegirine, microcline, natrolite in float, you are in the right ground. Field specimens usually show a fibrous, acicular, radiating clusters habit, so train your eye for that shape before scanning the outcrop.






