Hechtsbergite is a rare copper bismuth arsenate mineral typically found as small, vibrant green acicular crystals or radial tufts. It is most frequently encountered in the oxidation zones of hydrothermal veins, particularly in the Black Forest region of Germany.

Hardness

Mohs

Luster

Vitreous

Streak

Light Green

Transparency

Translucent

mineralrareMixite Group family

Hechtsbergite

Hardness: 3
Luster: Vitreous
Streak: Light Green
Transparency: 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 3 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Hechtsbergite leaves a light green streak.
3
Read the luster
Hold the specimen under a strong light. Hechtsbergite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: dark green, emerald green.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: acicular crystals, radial aggregates, crusts.

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 — Hechtsbergite leaves light green, Mixite leaves white.

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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: Bi₂Cu(OH)₆(AsO₄)
Mohs hardness: 3
Density: 4.9 g/cm³
Colors: Dark Green Emerald Green
Streak: Light Green
Luster: Vitreous
Transparency: Translucent
Crystal system: Hexagonal
Crystal habit: Acicular Crystals, Radial Aggregates, Crusts
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Veins in Granite
Typical price: $50-300 per specimen

Where rockhounds find hechtsbergite

Classic worldwide localities

Hechtsberg, Germany
Schwarzwald, Germany

Field-hunting tip

Look in hydrothermal veins in granite country — that is the host setting where hechtsbergite typically forms. If you start seeing bismutite, quartz, mimetite in float, you are in the right ground. Field specimens usually show a acicular crystals, radial aggregates, crusts habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify hechtsbergite?+

Mohs hardness is 3. It typically shows a vitreous luster. The streak is light green. Common colors include dark green, emerald green.

Where is hechtsbergite found?+

Notable localities include Hechtsberg, Germany; Schwarzwald, Germany.

How much is hechtsbergite 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.

Is hechtsbergite safe to handle?+

It contains toxic constituents. Contains arsenic and bismuth; wash hands thoroughly after handling and avoid ingestion or inhalation of dust. Handle with care, avoid grinding or breathing dust, and store separately.

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, Quartz, Mimetite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does hechtsbergite form in?+

Hechtsbergite typically forms in hydrothermal veins in granite. 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.