Roselite is a striking cobalt-bearing arsenate known for its intense rose-red to magenta coloration. It typically forms as small, attractive prismatic crystals or encrusting aggregates, often found associated with other cobalt minerals in hydrothermal veins.
Is this roselite?
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 roselite with a known reference. Roselite sits at Mohs 3.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: light red.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: dark rose red, pink.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: druse, mammillary, spherical.
Often confused with
Roselite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Roselite is noticeably harder (Mohs 3.5 vs. 1.5-2.5); streak differs, so Roselite leaves light red, Erythrite leaves pale red to pink; luster reads vitreous on Roselite and subadamantine, pearly on cleavages on Erythrite.
How to tell apart: Cobaltite is the harder of the two (Mohs 5.5 vs. 3.5); streak differs, so Roselite leaves light red, Cobaltite leaves grayish black; luster reads vitreous on Roselite and metallic on Cobaltite.
Often found alongside roselite
Minerals reported to co-occur with roselite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ca₂Co(AsO₄)₂·2H₂O
- Mohs hardness
- 3.5
- Density
- 3.46-3.74 g/cm³
- Colors
- Dark rose redPink
- Streak
- Light red
- Luster
- Vitreous
- Transparency
- Transparent to translucent
- Crystal system
- Monoclinic
- Crystal habit
- Druse, mammillary, spherical
- Cleavage
- On {010}, perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A rare secondary mineral in cobalt-bearing hydrothermal mineral deposits
Where rockhounds find roselite
Classic worldwide localities
- Rappold and Daniel mines, Schneeberg, Saxony, Germany
- Friedrich Christian mine, Wildschapbachtal, and the Anton mine, Heubachtal, near Schiltach, Black Forest, Germany
- Bou Azzer, Morocco
- Talmessi mine, 35 km west of Anarak, Iran
- Huercal Overa, Almería Province, and at Molvizar, Granada Province, Spain
Field-hunting tip
Where it forms: A rare secondary mineral in cobalt-bearing hydrothermal mineral deposits. If you start seeing talmessite in float, you are in the right ground. Typical habit: druse, mammillary, spherical. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify roselite?+
Where is roselite found?+
Is roselite safe to handle?+
What rocks look like roselite?+
What minerals are found with roselite?+
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Find roselite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
