mineral

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Hardness: 6.0-6.5 on Mohs scale. Color: Pale brass-yellow to brassy metallic grey. Luster: Metallic. Crystal structure: Isometric/cubic. Cleavage: Poor/indistinct. Specific gravity: ~4.9-5.2.

Hardness: 6
Color: Pale brass-yellow to brassy metallic grey
Luster: Metallic

Identified July 25, 2026More mineral →

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Physical properties

Hardness: 6.0-6.5 on Mohs scale. Color: Pale brass-yellow to brassy metallic grey. Luster: Metallic. Crystal structure: Isometric/cubic. Cleavage: Poor/indistinct. Specific gravity: ~4.9-5.2.

Formation & geological history

Forms in hydrothermal veins, metamorphic rocks, sedimentary rocks (such as dark shales), and magmatic deposits under various temperature conditions.

Uses & applications

Historically used as a source of sulfur and sulfuric acid. Today, it is mainly popular among mineral collectors, used in ornamental items, and researched for potential photovoltaic applications.

Geological facts

Earned the nickname 'Fool's Gold' during gold rushes because its brassy color and metallic sheen led inexperienced prospectors to mistake it for genuine gold.

Field identification & locations

Easily identified by its hardness (harder than gold, cannot be scratched by a knife), brittle nature (crushes to powder rather than flattening), greenish-black streak, and cubic or pyritohedral crystal habits. Commonly found worldwide, including USA, Peru, Spain, and Russia.