RocksdayGold vs Pyrite
How to tell them apart
A native metal that never tarnishes. In nature it occurs as nuggets, flakes in stream gravel and wires in quartz veins.
Photo: Alchemist-hp (talk) www.pse-mendelejew.de, CC BY-SA 3.0 de
Brassy iron sulfide famous as 'fool's gold'. It often forms startlingly perfect cubes with fine parallel lines on the faces.
Photo: Ivar Leidus, CC BY-SA 4.0
Quick tests
- Scratch glass: Pyrite scratches glass (Mohs 6–6.5); Gold can't (Mohs 2.5–3).
- Streak (rub on unglazed porcelain): Gold leaves a golden yellow streak; Pyrite leaves greenish black.
- Heft: Gold feels noticeably heavier for its size (specific gravity 15.5–19.3 vs 4.95–5.1).
Key differences
- Pyrite is brittle, hard and leaves a black streak.
- Gold is soft, bendable, has a golden streak and is about four times as heavy.
Side by side
| Property | Gold | Pyrite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 2.5–3 | 6–6.5 |
| Luster | Metallic | Metallic |
| Streak | Golden yellow | Greenish black |
| Colors | Gold | Gold |
| Crystal system | Cubic | Cubic |
| Specific gravity | 15.5–19.3 | 4.95–5.1 |
| Formula | Au | FeS₂ |
| Found in | Witwatersrand, South Africa; Carlin Trend, Nevada | Navajún, Spain; Huanzala, Peru |
Properties that are the same for both are grayed out.
How to identify gold
- Extremely heavy — sinks instantly in a gold pan.
- Bends and flattens instead of breaking.
- Golden streak.
- Stays bright yellow in shade and sun alike.
Crystal system: Cubic
Full Gold guide →How to identify pyrite
- Pale brass-yellow metallic color.
- Streak is greenish black, not gold.
- Hard and brittle — it shatters rather than flattens when struck.
- Cubes with striated faces, or twelve-sided pyritohedrons.
Crystal system: Cubic
Full Pyrite guide →More comparisons
Could you tell them apart from a blurry close-up?
Play today's Rocksday