Hechtsbergite is a rare bismuth vanadate that forms brown rounded or etched crystals. It occurs in cavities in gneiss. Associated minerals include bismutite, namibite and eulytite. It was first described from Hechtsberg quarry, near Hausach, Black Forest, Germany.

Hardness

4.5

Mohs

Luster

Adamantine

Streak

Yellow

Transparency

Transparent to translucent

mineralrareMixite Group family

Hechtsbergite

Hardness: 4.5
Luster: Adamantine
Streak: Yellow
Transparency: Transparent to translucent

Is this hechtsbergite?

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 hechtsbergite with a known reference. Hechtsbergite sits at Mohs 4.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: yellow.
3
Read the luster
Hold the specimen under a strong light. Luster: adamantine.
4
Match the color range
Compare against the expected color range: brown.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: euhedral crystals.

Often confused with

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

mineral

Mixite

Mohs 3-4

How to tell apart: Streak differs, so Hechtsbergite leaves yellow, Mixite leaves pale bluish green; luster reads adamantine on Hechtsbergite and vitreous, silky in aggregates on Mixite.

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Often found alongside hechtsbergite

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

All properties

Chemical formula: Bi₂O(VO₄)(OH)
Mohs hardness: 4.5
Density: 6.87 g/cm³
Colors: Brown
Streak: Yellow
Luster: Adamantine
Transparency: Transparent to translucent
Crystal system: Monoclinic
Crystal habit: Euhedral crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: In cavities in gneiss

Where rockhounds find hechtsbergite

Classic worldwide localities

Hechtsberg quarry, near Hausach, Black Forest, Germany

Field-hunting tip

Where it forms: In cavities in gneiss. If you start seeing bismutite, namibite, eulytite in float, you are in the right ground. Typical habit: euhedral crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify hechtsbergite?+

Mohs hardness is 4.5. Luster: adamantine. The streak is yellow. Common colors include brown.

Where is hechtsbergite found?+

Notable localities include Hechtsberg quarry, near Hausach, Black Forest, Germany.

Is hechtsbergite safe to handle?+

Hechtsbergite contains vanadium. Contains vanadium, which is toxic if ingested or inhaled as dust. Wash hands thoroughly after handling and avoid creating dust.

What rocks look like hechtsbergite?+

Hechtsbergite is most often confused with Mixite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with hechtsbergite?+

Hechtsbergite commonly co-occurs with Bismutite, Namibite, Eulytite, Mixite, Beyerite, Chrysocolla. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does hechtsbergite form in?+

Where it forms: In cavities in gneiss. Working float back to the host body is the standard way to chase a fresh occurrence.

What is hechtsbergite used for?+

Hechtsbergite is used in collector.

Find hechtsbergite on the map

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