RocksdayMalachite vs Rosasite
How to tell them apart
A vivid green copper carbonate with bold light-and-dark banding. It forms where copper deposits weather near the surface.
Photo: JJ Harrison (https://www.jjharrison.com.au/), CC BY-SA 3.0
A copper zinc carbonate forming small blue-green balls of radiating fibers.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Quick tests
- Streak (rub on unglazed porcelain): Malachite leaves a light green streak; Rosasite leaves light blue.
Key differences
- Malachite is pure green and banded.
Side by side
| Property | Malachite | Rosasite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 3.5–4 | 4 |
| Luster | Silky to dull | Silky to vitreous |
| Streak | Light green | Light blue |
| Colors | Green | Blue, Green |
| Crystal system | Monoclinic | Monoclinic |
| Specific gravity | 3.6–4.05 | 4–4.2 |
| Formula | Cu₂CO₃(OH)₂ | (Cu,Zn)₂CO₃(OH)₂ |
| Found in | Katanga, DR Congo; Ural Mountains, Russia | Ojuela mine, Mexico; Rosas mine, Sardinia |
Properties that are the same for both are grayed out.
How to identify malachite
- Bright green with concentric light/dark bands.
- Fizzes in acid.
- Feels heavy for a stone.
- Light green streak.
Crystal system: Monoclinic
Full Malachite guide →How to identify rosasite
- Blue-green spheres, often on brown limonite.
- Radiating fibers inside when broken.
- Fizzes in acid.
Crystal system: Monoclinic
Full Rosasite guide →More comparisons
Could you tell them apart from a blurry close-up?
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