Potassic-fluoro-pargasite is a relatively rare member of the complex amphibole supergroup, often found in metamorphic environments like skarns or marbles. Collectors look for its well-defined, stubby prismatic crystals, which are typically shades of dark green to black due to its specific chemical composition. It is best identified through laboratory analysis of its characteristic potassium and fluorine-rich chemistry.
Is this potassic-fluoro-pargasite?
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-pargasite with a known reference. Potassic-fluoro-pargasite sits at Mohs 6 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Potassic-fluoro-pargasite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Potassic-fluoro-pargasite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: dark green, brownish-green, black.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic crystals.
Often confused with
Potassic-fluoro-pargasite vs. its common look-alikes — and how to tell them apart in the field.
How to tell apart: Streak differs — Potassic-fluoro-pargasite leaves white, Hornblende leaves grayish-white.
How to tell apart: Luster reads vitreous on Potassic-fluoro-pargasite and vitreous to silky on Actinolite.
Often found alongside potassic-fluoro-pargasite
Minerals reported to co-occur with potassic-fluoro-pargasite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- KCa₂Mg₄Al(Si₆Al₂)O₂₂F₂
- Mohs hardness
- 6
- Density
- 3.1-3.3 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic Crystals
- Cleavage
- Perfect On {110}
- Rarity
- Rare
- Uses
- Collector, Research
- Host rock
- Metamorphic Rocks
- Typical price
- $20-150 per specimen depending on crystal size and quality
Where rockhounds find potassic-fluoro-pargasite
Classic worldwide localities
- Kola Peninsula, Russia
- Pargas, Finland
- Madagascar
- Canada
Field-hunting tip
Look in metamorphic rocks country — that is the host setting where potassic-fluoro-pargasite typically forms. If you start seeing phlogopite, calcite, diopside 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.
Common questions
How do you identify potassic-fluoro-pargasite?+
Where is potassic-fluoro-pargasite found?+
How much is potassic-fluoro-pargasite worth?+
What rocks look like potassic-fluoro-pargasite?+
What minerals are found with potassic-fluoro-pargasite?+
What kind of rock does potassic-fluoro-pargasite form in?+
What is potassic-fluoro-pargasite used for?+
Find potassic-fluoro-pargasite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
