mineral

Pyrite

Iron Sulfide (FeS2)

AI-generated identification · may be incorrect

Hardness: 6-6.5 Mohs; Color: Brass-yellow; Luster: Metallic; Crystal Structure: Isometric; Cleavage: Poor/Indistinct; Specific Gravity: 4.9-5.2

Hardness: 6-6
Color: Brass-yellow
Luster: Metallic

Identified May 6, 2026More mineral →

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Physical properties

Hardness: 6-6.5 Mohs; Color: Brass-yellow; Luster: Metallic; Crystal Structure: Isometric; Cleavage: Poor/Indistinct; Specific Gravity: 4.9-5.2

Formation & geological history

Formed in variety of geological settings including hydrothermal veins, sedimentary rocks, and contact metamorphic deposits. Can form at both high and low temperatures.

Uses & applications

Used as a source of sulfur and sulfuric acid in industry. Popular as a decorative stone for collectors and in inexpensive jewelry (often called 'marcasite'). Historical use as a spark source in wheel-lock firearms.

Geological facts

Commonly known as 'Fool's Gold' due to its deceptive color. Unlike gold, it is brittle and will shatter if struck, and it leaves a greenish-black streak when rubbed on a streak plate.

Field identification & locations

Identify by its hardness (scratches glass, unlike real gold which is soft), metallic brassy luster, and cubic or pyritohedral crystal habits. Found worldwide in mining districts.