Mineralpedia Details for Goethite
Goethite
Named to honor German poet, dramatist, and philosopher, Johann Wolfgang von Goethe. Goethite is a common mineral that forms as a product of the weathering of iron-bearing minerals oxygen-rich environments and is a component of iron ore, and it is a precipitate in hydrothermal, marine, and bog environments in reduced iron waters. Good crystals come from localities in Germany, the Czech Republic, England, France, and the United States.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/goethite.pdf
- Formula
- FeO(OH)
- Crystal System
- Orthorhombic
- Crystal Habit
- Acicular, Reniform, Radial
- Cleavage
- Perfect, Distinct, None
- Luster
- Adamantine - Silky
- Color
- brown, reddish brown, yellowish brown, brownish yellow, ocher yellow
- Streak
- yellowish brown
- Class
- Orthorhombic - Dipyramidal
- Fracture
- Hackly
- Hardness
- 5-5.5
- WebMineral
- View Goethite
- Mindat
- View Goethite
Goethite from Melrose, Iowa, United States
Black, prismatic, crystals in sprays 2mm long.
Goethite from Bou Azzer dist., Anti-Atlas, Morocco
Lath-like crystals to 1mm.
A 6x3cm vug filled with exceptional golden lath-like Goethite crystals to 1mm.
Goethite from Pribram, Bohemia, Czech Republic
Brassy looking, platy sprays of Goethite to 1mm covering the matrix.
Goethite from Montreal mine, Iron Co., Wisconsin, United States
Orange to brown compact fibrous banded Goethite. In this case it is an important component of ore in banded iron formations. At one time it was a primary ore in the oxidized surface portions of the Mesabi Iron Range iron deposits.
Goethite from Mahoning-Hull-Rust mine, Hibbing, Mesabi Range, St. Louis Co., Minnesota, United States
This is a large, heavy specimen and expect extra to ship beyond what the cart estimates. It is an impressive botryoidal or mammilary group of Goethite crystals. It is equally nice on each side and along the edges you can see the concentric, compact fibrous nature of the crystallization. Collected personally by Waidler during his time as a mining engineer in the iron mines of Minnesota.