mineral

Pyrite

Iron Sulfide (FeS2)

Hardness: 6-6.5 on Mohs scale; Color: Pale brass-yellow to golden; Luster: Metallic; Crystal Structure: Isometric/Cubic; Cleavage: Indistinct; Specific Gravity: 4.9-5.2.

Hardness: 6-6
Color: Pale brass-yellow to golden
Luster: Metallic

Identified March 27, 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 on Mohs scale; Color: Pale brass-yellow to golden; Luster: Metallic; Crystal Structure: Isometric/Cubic; Cleavage: Indistinct; Specific Gravity: 4.9-5.2.

Formation & geological history

Formed in high and low-temperature hydrothermal veins, by magmatic segregation, and as an accessory mineral in igneous and sedimentary rocks. It is found in deposits ranging from Precambrian to recent times.

Uses & applications

Historically used in the production of sulfuric acid and sulfur dioxide. Today, it is used in jewelry (as 'marcasite'), in radio receivers (crystal detectors), and as a popular specimen for collectors.

Geological facts

Commonly nicknamed 'Fool's Gold' due to its metallic luster and yellow hue which often confused prospectors. It can create sparks when struck against steel, leading to its name derived from the Greek word 'pyr' meaning fire.

Field identification & locations

Identify by its cubic crystal form, brassy color, and greenish-black streak (real gold has a yellow streak). Commonly found worldwide, with notable deposits in Spain, Italy, Kazakhstan, and the USA. Collectors look for sharp, mirror-finish cubic or pyritohedron shapes.