Pyrite
Pyrite · Mineral Specimen and Collector Mineral
Crystal System
Cubic; typically forms cubic, pyritohedral, or octahedral crystals, and massive or granular aggregates
Mineral Group
Sulfides
Chemical Formula
FeS2
Formation Process
Forms via hydrothermal veins, sedimentary deposition in reducing environments, and as an accessory mineral in igneous and metamorphic rocks
About This Crystal
Metallic, brass-yellow opaque cluster with a brilliant luster and granular, crystalline surface texture, commonly known as Fool's Gold
Physical Characteristics
Brass-yellow to pale yellow body color, greenish-black or brownish-black streak, conchoidal to uneven fracture, poor cleavage, specific gravity of approximately 5.0, brittle tenacity, and metallic luster
Optical Properties
Opaque with a strong metallic reflection, singly refracting in isotropic systems
Hardness & Durability
Origin Region
Notable sources include Peru, Spain, Italy, and the United States (such as Colorado); forms in igneous, metamorphic, and sedimentary environments
Hardness & Durability
Mohs hardness of 6 to 6.5, brittle toughness, moderately stable but can oxidize in humid conditions to form iron oxides/hydroxides
Care & Maintenance
Keep dry and away from high humidity to prevent oxidation and degradation; clean gently with a soft dry cloth, avoiding water and harsh chemicals
Rarity & Value
Common mineral worldwide; value depends on crystal perfection, matrix association, and size, with prices ranging from inexpensive to moderate for fine mineral specimens
Special Characteristics
Striated crystal faces, high metallic luster, and the ability to produce sparks when struck against steel
Lore & History
Historically used by ancient civilizations for starting fires (hence the name from the Greek pyr, meaning fire) and crafted into ancient jewelry by the Incas; in modern metaphysical practices, it is associated with abundance, vitality, and the solar plexus chakra