mineral

Pyrite in Shaly Matrix

Iron Sulfide (FeS2)

Hardness: 6-6.5 on Mohs scale; Color: Brass-yellow (mineral) and charcoal grey to black (matrix); Luster: Metallic; Crystal structure: Isometric (cubes, pyritohedrons); Cleavage: Indistinct; Specific gravity: 4.9-5.2

Hardness: 6-6
Color: Brass-yellow (mineral) and charcoal grey to black (matrix)
Luster: Metallic

Identified May 17, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Formed in sedimentary environments with high organic matter and low oxygen, typically through hydrothermal precipitation or diagenesis in shales. These can date from any geological age where anoxic conditions existed.

Uses & applications

Historically used as a source of sulfur and for fire-starting; currently used for ornamental pieces, mineral collecting, and occasionally as a minor ore of gold when associated with it.

Geological facts

Known as Fool's Gold due to its visual similarity to real gold. It is distinguished from gold by its brittleness (gold is malleable) and its ability to create sparks when struck against steel.

Field identification & locations

Identify in the field by its metallic luster, 'brass' color, and black or dark green streak when rubbed on unglazed porcelain. Commonly found in coal beds, shales, and hydrothermal veins worldwide.