RocksdayChrysocolla vs Hemimorphite
How to tell them apart
A blue-green hydrated copper silicate that forms crusts and fillings where copper deposits weather.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
A zinc silicate forming sky-blue bubbly crusts or white bladed crystals.
Photo: Ivar Leidus, CC BY-SA 4.0
Quick tests
- Hardness: Hemimorphite is clearly harder: Mohs 4.5–5 versus 2.5–3.5.
- Streak (rub on unglazed porcelain): Chrysocolla leaves a pale blue to white streak; Hemimorphite leaves white.
- Heft: Hemimorphite feels noticeably heavier for its size (specific gravity 3.4–3.5 vs 1.9–2.4).
Key differences
- Chrysocolla is softer and greener.
Side by side
| Property | Chrysocolla | Hemimorphite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 2.5–3.5 | 4.5–5 |
| Luster | Vitreous to earthy | Vitreous to silky |
| Streak | Pale blue to white | White |
| Colors | Blue, Green | Blue, White, Clear |
| Crystal system | Amorphous to cryptocrystalline | Orthorhombic |
| Specific gravity | 1.9–2.4 | 3.4–3.5 |
| Formula | (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O | Zn₄Si₂O₇(OH)₂·H₂O |
| Found in | Arizona; Peru | Yunnan, China; Chihuahua, Mexico |
Properties that are the same for both are grayed out.
How to identify chrysocolla
- Vivid blue to blue-green, often mixed with malachite or quartz.
- Soft and light; may stick slightly to the tongue.
- No crystals — crusts, veins and botryoidal masses.
Crystal system: Amorphous to cryptocrystalline
Full Chrysocolla guide →How to identify hemimorphite
- Pale sky-blue botryoidal crusts, or fans of colorless blades.
- Crystals have different shapes at each end.
- Does not fizz in acid.
Crystal system: Orthorhombic
Full Hemimorphite guide →More comparisons
Could you tell them apart from a blurry close-up?
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