Bergslagite is an exceptionally rare calcium beryllium arsenate mineral known primarily from the Langban iron-manganese mine in Sweden. It typically forms colorless to pale yellow tabular crystals and is frequently sought after by advanced systematic collectors for its unique chemistry and scarcity.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Bergslagite

Hardness: 5
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this bergslagite?

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 bergslagite with a known reference. Bergslagite sits at Mohs 5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Bergslagite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Bergslagite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, pale yellow.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals, subparallel aggregates.

Often confused with

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

Often found alongside bergslagite

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

All properties

Chemical formula: CaBeAsO₄(OH)
Mohs hardness: 5
Density: 3.84 g/cm³
Colors: Colorless White Pale Yellow
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Tabular Crystals, Subparallel Aggregates
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Metamorphic Manganese-iron Ore Deposits
Typical price: $50-300 per specimen depending on size and quality

Where rockhounds find bergslagite

Classic worldwide localities

Langban, Varmland, Sweden

Field-hunting tip

Look in metamorphic manganese-iron ore deposits country — that is the host setting where bergslagite typically forms. If you start seeing hediphane, hausmannite, baryte in float, you are in the right ground. Field specimens usually show a tabular crystals, subparallel aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify bergslagite?+

Mohs hardness is 5. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white, pale yellow.

Where is bergslagite found?+

Notable localities include Langban, Varmland, Sweden.

How much is bergslagite worth?+

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

Is bergslagite safe to handle?+

It contains toxic constituents. Contains arsenic, which is toxic; handle with care and wash hands thoroughly after handling. Do not ingest or inhale dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like bergslagite?+

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

What minerals are found with bergslagite?+

Bergslagite commonly co-occurs with Hediphane, Hausmannite, Baryte, Berzeliite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does bergslagite form in?+

Bergslagite typically forms in metamorphic manganese-iron ore deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is bergslagite used for?+

Bergslagite is used in collector.

Find bergslagite on the map

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