mineral

Pyrite

Iron Disulfide (FeS2)

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

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

Identified July 21, 2026More mineral →

Explore Pyrite in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

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

Formation & geological history

Forms in a wide variety of environments including sedimentary rocks, hydrothermal veins, and as an accessory mineral in igneous rocks. It forms through the reaction of iron and sulfur in oxygen-poor environments.

Uses & applications

Historically a source of sulfur and sulfuric acid; used in jewelry (marketed as 'marcasite'), as a grounding stone in crystal healing, and as a component in lithium batteries.

Geological facts

Often called 'Fool's Gold' because its color resembles real gold, though it is much harder and lacks gold's malleability. It can create sparks when struck against steel.

Field identification & locations

Identify by its brassy color, metallic luster, and blackish-green streak on a porcelain plate. Common in many environments worldwide, especially in Peru, Spain, and the USA.