Goethite named after the German polymath Johann Wolfgang von Goethe, is an iron bearing oxide mineral found in soil and other low-temperature environments. Goethite has been well known since prehistoric times for its use as a pigment. Evidence has been found of its use in paint pigment samples taken from the caves of Lascaux in France. It was first described in 1806 for occurrences in the Hollertszug Mine, Dermbach, Herdorf, Siegerland, Rhineland-Palatinate, Germany. In 2003, nanoparticulate authigenic goethite was shown to be the most common diagenetic iron oxyhydroxide in both marine and lake sediments. It is an iron oxyhydroxide. Goethite's hardness ranges from 5.0 to 5.5 on the Mohs Scale, and its specific gravity varies from 3.3 to 4.3. The mineral...'
Contributions by Vsmith, Chris.urs-o, and Shaddack.