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.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Barberiite

Hardness: 2
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this barberiite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch barberiite with a known reference. Barberiite sits at Mohs 2 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Barberiite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Barberiite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: tabular crystals, crusts.

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: 2
Density: 2.11 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Tabular Crystals, Crusts
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Fumaroles
Typical price: $50-300 per specimen

Where rockhounds find barberiite

Classic worldwide localities

Vulcano, Aeolian Islands, Italy

Field-hunting tip

Look in fumaroles country — that is the host setting where barberiite typically forms. If you start seeing sassolite, sal ammoniac, mascagnite in float, you are in the right ground. Field specimens usually show a tabular crystals, crusts habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify barberiite?+

Mohs hardness is 2. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white.

Where is barberiite found?+

Notable localities include Vulcano, Aeolian Islands, Italy.

How much is barberiite worth?+

Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like barberiite?+

Barberiite is most often confused with Salammoniac, Mascagnite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with barberiite?+

Barberiite commonly co-occurs with sassolite, sal ammoniac, mascagnite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does barberiite form in?+

Barberiite typically forms in fumaroles. Working float back to the host body is the standard way to chase a fresh occurrence.

What is barberiite used for?+

Barberiite is used in collector.

Find barberiite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.