Beshtauite is a rare ammonium sulfite hydrate found as a secondary mineral in volcanic fumaroles. It typically appears as small, colorless tabular crystals and is known primarily from its type locality at Mount Beshtau in the Caucasus Mountains.

Hardness

2-3

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareSulfur Oxysalt family

Beshtauite

Hardness: 2-3
Luster: Vitreous
Streak: White
Transparency: Transparent

No image

Is this beshtauite?

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 beshtauite with a known reference. Beshtauite sits at Mohs 2-3 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Beshtauite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Beshtauite 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: monoclinic. Typical habit: tabular crystals.

Often confused with

Beshtauite vs. its common look-alikes — and how to tell them apart in the field.

Often found alongside beshtauite

Minerals reported to co-occur with beshtauite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: (NH₄)₂(SO₃)·H₂O
Mohs hardness: 2-3
Density: 2.98 g/cm³
Colors: Colorless White
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Tabular Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Fumarolic Deposits
Typical price: $100-500 thumbnail

Where rockhounds find beshtauite

Classic worldwide localities

Beshtau Mountain, Russia

Field-hunting tip

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

Common questions

How do you identify beshtauite?+

Mohs hardness is 2-3. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white.

Where is beshtauite found?+

Notable localities include Beshtau Mountain, Russia.

How much is beshtauite worth?+

Typical asking prices fall in the range of $100-500 thumbnail. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like beshtauite?+

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

What minerals are found with beshtauite?+

Beshtauite commonly co-occurs with Mascagnite, Sulfur. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does beshtauite form in?+

Beshtauite typically forms in fumarolic deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is beshtauite used for?+

Beshtauite is used in collector.

Find beshtauite on the map

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