Minerals · common
Pyrite
Pyrite, commonly known as 'fool's gold,' is an iron sulfide with a metallic luster and pale brass-yellow color. Despite its name, it has significant industrial uses.
Also known as: fools gold, iron sulfide, brass yellow.
Pyrite properties at a glance
| Type | Minerals |
|---|---|
| Chemical formula | FeS2 |
| Mohs hardness | 6.5 |
| Crystal system | cubic |
| Luster | metallic |
| Streak | Greenish-black |
| Cleavage | Poor |
| Fracture | Conchoidal |
| Specific gravity | 5 |
| Transparency | opaque |
| Common colors | Brass Yellow, Pale Gold |
| Rarity | common |
Geology & background
Forms in a variety of geological environments from hydrothermal fluids, in sedimentary rocks, and as a replacement mineral.
Used in early firearms as a spark source and misidentified as gold throughout history.
How to identify Pyrite
- Check whether the specimen's color and texture match typical Pyrite examples.
- Photograph a fresh surface in natural light and avoid shadows, glare, or wet surfaces.
- Use hardness, streak, luster, grain size, and locality together; no single trait is enough for every specimen.
Full Pyrite identification guide: checklist, home tests and look-alikes →
Pyrite vs similar stones
Not sure it isn't something else? Side-by-side comparisons with the stones most often confused with Pyrite.
Where Pyrite is found
Pyrite is reported from multiple localities or geological settings. Exact locality should be verified from specimen provenance, maps, or field notes.
How much is Pyrite worth?
| Entry-level specimen | $2 |
|---|---|
| Typical collector specimen | $15 |
| Premium specimen | $100+ |
Value depends on size, condition, color, crystal quality, locality, rarity, preparation, and provenance. Treat this as educational guidance, not an appraisal.
Common uses
- Sulfuric acid production
- Jewelry
- Collector specimens
Interesting facts
- Name comes from Greek 'pyr' meaning fire, as it sparks when struck
- Used by ancient civilizations to start fires
- Sometimes contains microscopic gold inclusions
Care & safety
Treat Pyrite as a collector specimen unless hardness, cleavage, and fracture are confirmed.
Avoid inhaling dust. Do not cut, grind, or polish unknown specimens without eye protection and a properly rated respirator.
Pyrite FAQ
What is Pyrite?
Pyrite, commonly known as 'fool's gold,' is an iron sulfide with a metallic luster and pale brass-yellow color. Despite its name, it has significant industrial uses.
How much is Pyrite worth?
Entry-level Pyrite specimens sell for around $2, a typical collector specimen for about $15, and premium pieces for $100 or more. Value depends on size, condition, color, crystal quality, locality, rarity, preparation, and provenance. Treat this as educational guidance, not an appraisal.
How hard is Pyrite?
Pyrite has a Mohs hardness of 6.5. It scratches glass and a steel knife and cannot be scratched by a steel file.
Where is Pyrite found?
Notable sources of Pyrite include Spain, Peru, USA, Russia, and South Africa. Forms in a variety of geological environments from hydrothermal fluids, in sedimentary rocks, and as a replacement mineral..
What is Pyrite used for?
Pyrite is used for sulfuric acid production, jewelry, and collector specimens.
