Jørgensenite is an exceptionally rare fluoride mineral discovered in the famous cryolite deposit of Ivigtut, Greenland. It typically occurs as small tabular crystals associated with cryolite and chiolite, often requiring microscopic examination for positive identification.
Is this jørgensenite?
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 jørgensenite with a known reference. Jørgensenite sits at Mohs 3.5-4, 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: colorless, white.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: tabular crystals.
Often confused with
Jørgensenite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside jørgensenite
Minerals reported to co-occur with jørgensenite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₂Sr₁₄Na₂Al₁₂F₆₄(OH)₄
- Mohs hardness
- 3.5-4
- Density
- 3.89 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Semitransparent
- Crystal system
- Monoclinic
- Crystal habit
- Tabular crystals
- Cleavage
- Distinct
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In vugs and as fissure fillings in a cryolite deposit with other fluorides
Where rockhounds find jørgensenite
Classic worldwide localities
- Ivigtut cryolite deposit, Greenland
Field-hunting tip
Where it forms: In vugs and as fissure fillings in a cryolite deposit with other fluorides. If you start seeing jarlite, stenonite, thomsenolite in float, you are in the right ground. Typical habit: tabular crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify jørgensenite?+
Where is jørgensenite found?+
What rocks look like jørgensenite?+
What minerals are found with jørgensenite?+
What kind of rock does jørgensenite form in?+
What is jørgensenite used for?+
Find jørgensenite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
