Goethite
Goethite (FeO(OH)) named efter the German polymath Johann Wolfgang von Goethe (1749–1832), is an airn bearin oxide mineral foond in soil an ither law-temperatur environments. Goethite haes been weel kent syne prehistoric times for its uise as a pigment. Evidence haes been foond o its uise in paint pigment samples taken frae the caves o Lascaux in Fraunce. It wis first describit in 1806 for occurrences in the Hollertszug Mine, Dermbach, Herdorf, Siegerland, Rhineland-Palatinate, Germany.[3]
| Goethite | |
|---|---|
 Goethite, Restormel Royal Iron Mine, Cornwall, Ingland. | |
| General | |
| Category | Oxide meenerals |
| Formula (repeatin unit) | α-FeO(OH) |
| Strunz clessification | 04.FD.10 |
| Creestal seestem | Orthorhombic 2/m2/m2/m |
| Identification | |
| Colour | Yellaeish tae reiddish tae dark broun |
| Cleavage | Perfect 010 |
| Fractur | Uneven tae splintery |
| Mohs scale haurdness | 5 - 5.5 |
| Skinkle | Adamantine to dull |
| Streak | Broun, brounish yellae tae orange yellae |
| Speceefic gravity | 3.3 - 4.3 |
| Refractive index | Opaque tae sub-translucent |
| Fusibility | Fusible at 5 - 5.5 |
| Ither chairacteristics | Becomes magnetic in reducin flame |
| References | [1][2][3][4] |
In 2003, nanoparticulate authigenic goethite wis shawn tae be the maist common diagenetic airn oxyhydroxide in baith marine an loch sediments.[5]
References
eedit- ↑ Hurlbut, Cornelius S.; Klein, Cornelis (1985). Manual of Mineralogy (20th ed.). Wiley. ISBN 0-471-80580-7.
- ↑ http://webmineral.com/data/Goethite.shtml Webmineral data
- ↑ a b http://www.mindat.org/min-1719.html Mindat data with locations
- ↑ http://www.galleries.com/minerals/oxides/goethite/goethite.htm Archived 2011-10-16 at the Wayback Machine Mineral galleries
- ↑ van der Zee, C.; Roberts, D.; Rancourt, D. G.; Slomp, C. P. (2003). "Nanogoethite is the dominant reactive oxyhydroxide phase in lake and marine sediments". Geology. 31 (11): 993–996. Bibcode:2003Geo....31..993V. doi:10.1130/G19924.1.