RocksdayAnnabergite vs Erythrite
The quickest way to tell Annabergite from Erythrite: Annabergite leaves a white streak; Erythrite leaves pale pink.
Apple-green nickel arsenate, the nickel version of pink erythrite. It stains rock where nickel ores weather.
Photo: Didier Descouens, CC BY-SA 3.0
A crimson-pink cobalt arsenate that forms where cobalt ores weather.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Quick tests
- Streak (rub on unglazed porcelain): Annabergite leaves a white streak; Erythrite leaves pale pink.
Key differences
- Erythrite is crimson pink (cobalt), not apple green.
- Annabergite is apple green (nickel), not crimson pink.
Side by side
| Property | Annabergite | Erythrite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 1.5–2.5 | 1.5–2.5 |
| Luster | Pearly to vitreous | Adamantine to pearly |
| Streak | White | Pale pink |
| Colors | Green | Pink, Purple, Red |
| Crystal system | Monoclinic | Monoclinic |
| Specific gravity | 3–3.1 | 3.06 |
| Formula | Ni₃(AsO₄)₂·8H₂O | Co₃(AsO₄)₂·8H₂O |
| Found in | Annaberg, Germany; Laurium, Greece | Bou Azzer, Morocco; Cobalt, Ontario |
Properties that are the same for both are grayed out.
How to identify annabergite
- Pale apple-green crusts or tiny crystals.
- Very soft.
- On dark nickel ore, not the crimson of cobalt bloom.
Crystal system: Monoclinic
Full Annabergite guide →How to identify erythrite
- Crimson to pink crusts or radiating crystals.
- Very soft.
- Often coats dark cobalt ores.
Crystal system: Monoclinic
Full Erythrite guide →More comparisons
Frequently asked questions
What is the difference between annabergite and erythrite?
Annabergite is a mineral with a Mohs hardness of 1.5–2.5 and a pearly to vitreous luster, usually green. Erythrite is a mineral with a Mohs hardness of 1.5–2.5 and an adamantine to pearly luster, usually pink, purple or red.
How can you tell annabergite from erythrite?
Annabergite leaves a white streak; Erythrite leaves pale pink. Erythrite is crimson pink (cobalt), not apple green. Annabergite is apple green (nickel), not crimson pink.
Could you tell them apart from a blurry close-up?
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