Minerals identify

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Goethite

Oxide mineral hydroxide subgroup

Goethite (/ˈɡɜːrtaɪt/) is a mineral of the diaspore group, consisting of iron(III) oxide-hydroxide , specifically the "α" polymorph. It is found in soil and other low-temperature environments such as sediment. Goethite has been well known since ancient times for its use as a pigment (brown ochre ). Evidence has been found of its use in paint pigment samples taken from the caves of Lascaux. It was first described in 1806 based on samples found in the Hollertszug Mine in Herdorf The mineral was named after the German and poet Johann Wolfgang von Goethe (1749–1832).

Identification

Color of mineral

Red
Brown
Yellow
Black

Mohs scale ( mineral hardness )

5

The streak

Brown
Yellow
Orange

Luster ( interacts light )

Adamantine
Dull

Crystal ( diaphaneity )

Orthorhombic