Goethita
Goethita is a mineral with formula FeO(OH), in the Óxidos group. This specimen comes from Filón Sur, Minas de Tharsis, Alosno, Huelva, Andalucía, España and joined the Terrium collection in 2025.
Description
Botryoidal mass of goethite with coppery iridescence, black and reddish-brown surface, and submetallic lustre. Compact rounded reliefs, dark rough areas, and ferruginous bands on the sides.
History of this specimen
I collected it in May 2025 on a field trip with Óscar.
About Goethita
Goethite is a hydrated iron oxide that commonly occurs in botryoidal, acicular or massive habits. It is a typical product of the alteration of iron minerals. It is opaque, with a lustre between submetallic and earthy.
About the locality
Tharsis forms part of the Iberian Pyrite Belt, a mining-metallogenetic complex with more than 5,000 years of history. The goethites from Filón Sur became well known for their iridescent patina, recognised since the reopening of the mine in 2007.
Technical data
- Catalogue No.
- 0448
- Internal reference
- T0055
- Composition
- FeO(OH)
- Name
- Goethita
- Group
- Óxidos
- Matrix
- Ferrosa
- Mine
- Filón Sur, Minas de Tharsis
- District / Municipality
- Alosno
- Province
- Huelva
- Region
- Andalucía
- Country
- España
- Size (cm)
- 10 x 5 x 4
- Acquired
- 2025
- Etymology
- Named after the German mineralogist Johann Wolfgang von Goethe, in recognition of his interest in mineralogy.
- Quality
- Buena
- Value trend
- Estable
Related specimens
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- Abernathyita — España
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- Aerenita — España
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- Analcima — España
- Analcima — España