Mineral

Pyrite in Quartzite/Graphite Matrix

Iron Sulfide (FeS2)

Hardness: 6-6.5 (Mohs), Color: Pale brass-yellow, Luster: Metallic, Crystal Structure: Isometric, Cleavage: Indistinct, Specific Gravity: 4.8-5.0

Hardness: 6-6

Identified April 7, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

Physical properties

Hardness: 6-6.5 (Mohs), Color: Pale brass-yellow, Luster: Metallic, Crystal Structure: Isometric, Cleavage: Indistinct, Specific Gravity: 4.8-5.0

Formation & geological history

Formed in high and low-temperature hydrothermal veins, by magmatic segregation, or as a late-stage mineral in igneous rocks; also common in sedimentary and metamorphic environments.

Uses & applications

Major ore for sulfur and sulfuric acid production; used as a gemstone (marcasite jewelry), for mineral specimens, and in solar panels research.

Geological facts

Commonly known as "Fool's Gold" because it is often mistaken for real gold by novice prospectors, although it is much harder and more brittle than actual gold.

Field identification & locations

Identify by its metallic luster and brassy color. Unlike gold, it will produce a greenish-black streak when rubbed on a porcelain plate and will spark when struck with steel.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

mineral