RocksdayAzurite vs Linarite
The quickest way to tell Azurite from Linarite: A fingernail scratches Linarite (Mohs 2.5) but not Azurite (Mohs 3.5–4).
An intensely deep blue copper carbonate. Over time it slowly converts to green malachite, and the two are often found together.
Photo: Ivar Leidus, CC BY-SA 4.0
A deep blue lead-copper sulfate, often mistaken for azurite. It does not fizz, and it is much heavier.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Quick tests
- Fingernail: A fingernail scratches Linarite (Mohs 2.5) but not Azurite (Mohs 3.5–4).
- Acid (vinegar or dilute HCl): Azurite fizzes; Linarite doesn't.
- Streak (rub on unglazed porcelain): Azurite leaves a light blue streak; Linarite leaves pale blue.
- Heft: Linarite feels noticeably heavier for its size (specific gravity 5.3–5.4 vs 3.77–3.78).
Key differences
- Azurite fizzes in acid and is lighter.
Side by side
| Property | Azurite | Linarite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 3.5–4 | 2.5 |
| Luster | Vitreous | Adamantine to vitreous |
| Streak | Light blue | Pale blue |
| Colors | Blue | Blue |
| Crystal system | Monoclinic | Monoclinic |
| Specific gravity | 3.77–3.78 | 5.3–5.4 |
| Formula | Cu₃(CO₃)₂(OH)₂ | PbCu(SO₄)(OH)₂ |
| Found in | Bisbee, Arizona; Tsumeb, Namibia | Linares, Spain; Arizona |
Properties that are the same for both are grayed out.
How to identify azurite
- Deep 'azure' blue, often with green malachite.
- Fizzes in acid.
- Soft — a knife scratches it.
- Light blue streak.
Crystal system: Monoclinic
Full Azurite guide →How to identify linarite
- Intense blue crystals or crusts.
- A fingernail almost scratches it.
- No fizz in acid — azurite fizzes.
- Surprisingly heavy.
Crystal system: Monoclinic
Full Linarite guide →More comparisons
Frequently asked questions
What is the difference between azurite and linarite?
Azurite is a mineral with a Mohs hardness of 3.5–4 and a vitreous luster, usually blue. Linarite is a mineral with a Mohs hardness of 2.5 and an adamantine to vitreous luster, usually blue.
How can you tell azurite from linarite?
A fingernail scratches Linarite (Mohs 2.5) but not Azurite (Mohs 3.5–4). Azurite fizzes; Linarite doesn't. Azurite leaves a light blue streak; Linarite leaves pale blue. Linarite feels noticeably heavier for its size (specific gravity 5.3–5.4 vs 3.77–3.78). Azurite fizzes in acid and is lighter.
Could you tell them apart from a blurry close-up?
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