Bieberite is a rare, water-soluble sulfate mineral characterized by its distinct rose-red to pink color. It typically forms as efflorescent crusts or fibrous aggregates in the oxidation zones of cobalt-rich hydrothermal veins.
Is this bieberite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch bieberite with a known reference. Bieberite sits at Mohs 2, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: pinkish red, flesh pink.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: encrustations, stalactitic.
Often confused with
Bieberite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside bieberite
Minerals reported to co-occur with bieberite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CoSO₄·7H₂O
- Mohs hardness
- 2
- Density
- 1.96 g/cm³
- Colors
- Pinkish redFlesh pink
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Encrustations, stalactitic
- Cleavage
- On {001}, perfect; on {110}, fair
- Rarity
- Rare
- Uses
- Collector
- Host rock
- An uncommon oxidation product of cobalt-bearing sulfide–arsenides
Where rockhounds find bieberite
1 mapped spotsClassic worldwide localities
- Island Mountain, Trinity Co., California, USA
- Ajo, Pima Co., Arizona, USA
- Dolly prospect, Emery Co., Utah, USA
- Bieber, near Hanau, Hesse, Germany
- Siegen, Westphalia, Germany
- Wittichen, Black Forest, Germany
Field-hunting tip
Where it forms: An uncommon oxidation product of cobalt-bearing sulfide–arsenides. If you start seeing erythrite, annabergite, pharmacolite in float, you are in the right ground. Typical habit: encrustations, stalactitic. Train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Utah. Start trip planning there.
Common questions
How do you identify bieberite?+
Where is bieberite found?+
Can I find bieberite in the United States?+
Is bieberite safe to handle?+
What rocks look like bieberite?+
What minerals are found with bieberite?+
What kind of rock does bieberite form in?+
What is bieberite used for?+
Find bieberite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
