Barberiite is an extremely rare ammonium borofluoride mineral found in high-temperature fumaroles. It typically occurs as small tabular crystals or crusts coating volcanic rocks in association with other rare sublimates.
Is this barberiite?
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 barberiite with a known reference. Barberiite sits at Mohs 1, 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.
- 5Look at form & habitCrystal system: orthorhombic. Typical habit: aggregates, granular.
Often confused with
Barberiite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside barberiite
Minerals reported to co-occur with barberiite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (NH₄)BF₄
- Mohs hardness
- 1
- Density
- 1.89 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent to translucent
- Crystal system
- Orthorhombic
- Crystal habit
- Aggregates, granular
- Cleavage
- Perfect on {100}; good on {010}; good on {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Formed by fumarolic activity, stable at ground temperatures between 200°C and 600°C
Where rockhounds find barberiite
Classic worldwide localities
- Fossa crater, Vulcano, Lipari Islands, Italy
Field-hunting tip
Where it forms: Formed by fumarolic activity, stable at ground temperatures between 200°C and 600°C. If you start seeing malladrite, realgar, bismuthinite in float, you are in the right ground. Typical habit: aggregates, granular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify barberiite?+
Where is barberiite found?+
What rocks look like barberiite?+
What minerals are found with barberiite?+
What kind of rock does barberiite form in?+
What is barberiite used for?+
Find barberiite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
