RocksdayPyrite
Brassy iron sulfide famous as 'fool's gold'. It often forms startlingly perfect cubes with fine parallel lines on the faces.
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.
Often confused with
GoldGold is soft, bendable, has a golden streak and is about four times as heavy.
Compare side by side
ChalcopyriteChalcopyrite is softer, deeper yellow and tarnishes to iridescent colors.
Compare side by side
Where it's found
- Navajún, Spain
- Huanzala, Peru
- Illinois coal fields
Uses
Once a source of sulfuric acid; today mostly collected.
Rock tumbling
Can be tumbled with care. Hard enough, but brittle and heavy, and it can tarnish if left wet.
Did you know?
The name comes from Greek pyr, 'fire' — pyrite throws sparks when struck with steel.
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