Goethite

Goethite is an iron oxide-hydroxide mineral that has been known and used by people since ancient times. Many thousands of years ago it was used to make pigments. The famous cave paintings of Lascaux, France used goethite to make lifelike paintings of ice age animals. Today it is used as an iron ore. It comes in many crystalline forms, radial acicular, and botryoidal as well as stalactitic, massive and encrustations.

Goethite commonly forms a pseudomorph after other minerals, especially Marcasite, Pyrite, Siderite, and Gypsum.

Goethite was first described in 1806 in Germany and named after the German philosopher, poet, and mineral enthusiast Johann Wolfgang von Goethe.

Mineral Properties of Geothite

Chemical formula: Iron Oxide-Hydroxide aFeO(OH)
Color(s): reddish to dark brown or black
Streak: brown, brownish yellow to orange yellow
Luster: Admantine
Transparency: Opaque
Crystal system: Orthorhombic
Specific Gravity: 3.3-4.3
Hardness (Mohs): 5 - 5.5
Cleavage: Perfect
Fracture: Uneven to splintery
Uses: iron ore, pigment, collectable mineral
Location: World Wide Distribution