Potassic-fluoro-richterite is a rare member of the amphibole supergroup often occurring as elongated, prismatic or needle-like crystals. It is typically found in metasomatized skarn deposits or alkaline intrusive complexes, prized by collectors for its crystal habit and relationship to other rare minerals in the richterite series.
Is this potassic-fluoro-richterite?
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 potassic-fluoro-richterite with a known reference. Potassic-fluoro-richterite 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: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: yellow, brown, green, colorless.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic crystals, acicular, fibrous.
Often confused with
Potassic-fluoro-richterite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside potassic-fluoro-richterite
Minerals reported to co-occur with potassic-fluoro-richterite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- KNaCaMg₅Si₈O₂₂F₂
- Mohs hardness
- 5-6
- Density
- 3.0-3.1 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic crystals, acicular, fibrous
- Cleavage
- Perfect prismatic
- Rarity
- Rare
- Uses
- Collector
- Host rock
- metasomatized skarns and alkaline igneous rocks
Where rockhounds find potassic-fluoro-richterite
Classic worldwide localities
- Badakhshan, Afghanistan
- Khibiny Massif, Russia
- Mont Saint-Hilaire, Canada
Field-hunting tip
Where it forms: metasomatized skarns and alkaline igneous rocks. If you start seeing diopside, calcite, apatite in float, you are in the right ground. Typical habit: prismatic crystals, acicular, fibrous. Train your eye for that shape before scanning the outcrop.







