goethite

/goh"thuyt, gue"tuyt/, n.
a very common mineral, iron hydroxide, HFeO2, occurring in crystals, but more commonly in yellow or brown earthy masses: an ore of iron.
[1815-25; named after GOETHE; see -ITE1]

* * *

Widespread iron hydroxide mineral, α-FeO(OH), the most common ingredient of iron rust.

In terms of relative abundance, it is second only to hematite (α-Fe2O3) among iron oxides. Goethite varies in colour from yellow-brown to red and is the source for the pigment known as yellow ocher; it is also the primary mineral in some important iron ores, such as those in the Alsace-Lorraine basin in France. Other important deposits are found in the southern Appalachian Mountains of the U.S., and in Brazil, South Africa, Russia, and Australia.

* * *

 a widespread iron oxide mineral [α-FeO(OH)] and the most common ingredient of iron rust. It was named in 1806 for J.W. von Goethe, a German poet and philosopher with a keen interest in minerals. The name was originally applied to lepidocrocite [γ-FeO(OH)], a less common mineral with the same chemical composition as goethite but with a different crystal structure. In goethite, oxygen and hydroxyl anions are closely packed in hexagonal arrays, while in lepidocrocite they are arranged in cubic arrays; in both structures, however, iron cations occupy the octahedral interstices.

      In terms of relative abundance, goethite is second only to hematite (α-Fe2O3) among iron oxides. Goethite is normally formed under oxidizing conditions as a weathering product of iron minerals (e.g., pyrite, magnetite). Because it is formed near the surface, goethite is the major component of the gossan of iron sulfide deposits in locations such as Arizona and of lateritic deposits in places such as Cuba. It also occurs as a direct precipitate in marine and meteoric waters, and deposits accumulate in springs and marshes.

      Goethite is the source for the pigment known as yellow ochre; it is also the primary mineral in some important iron ores, such as those in the Alsace-Lorraine basin in France. Other important goethite deposits are found in the southern Appalachians, U.S.; Brazil; South Africa; Russia; and Australia.

      Goethite varies in colour from yellow-brown to red. It is composed of about 80 to 90 percent Fe2O3 and approximately 10 percent water. When dehydrated, goethite forms hematite; upon hydration, goethite becomes limonite. For detailed physical properties, see oxide mineral (table).

* * *


Universalium. 2010.

Look at other dictionaries:

  • Goethite — Catégorie IV : oxydes et hydroxydes[1] Goethite Restormel Cornouailles Angleterre …   Wikipédia en Français

  • goethite — n. (Miner.) an oxide of iron. Syn: gothite. [WordNet 1.5] …   The Collaborative International Dictionary of English

  • goethite — ● goethite nom féminin (de Gœthe, nom propre) Oxyde naturel hydraté de fer FeOOH, orthorhombique …   Encyclopédie Universelle

  • goethite — [gʉ′thīt΄, gʉr′tīt΄; gō′thīt, gō′tīt; ] also [, gō′thīt΄] n. [Ger göthit, after GOETHE Johann Wolfgang von, in honor of his studies in geology and mineralogy] a hard, brownish, orthorhombic mineral, FeO(OH), an ore of iron; iron hydroxide …   English World dictionary

  • Goethite — Infobox mineral name = Goethite category = boxwidth = boxbgcolor = imagesize = caption = Goethite,from Minas Gerais, Brazil formula = α IronOxygen(Hydroxide) molweight = color = Yellowish to reddish to dark brown habit = system = Orthorhombic… …   Wikipedia

  • Goethite — Gothite G[ o] thite, gothite go thite, or Goethite Goe thite, n. [After the poet G[ o]the.] (Min.) A hydrous oxide of iron ({HFeO2}), occurring in prismatic crystals, also massive, with a fibrous, reniform, or stalactitic structure. The color… …   The Collaborative International Dictionary of English

  • goethite — getitas statusas T sritis chemija apibrėžtis Mineralas. formulė FeO·OH atitikmenys: angl. goethite rus. гетит …   Chemijos terminų aiškinamasis žodynas

  • goethite — noun Etymology: German Göthit, from J. W. von Goethe Date: circa 1823 a common brown mineral that consists of an iron hydrogen oxide and is the commonest constituent of many forms of natural rust …   New Collegiate Dictionary

  • goethite — noun An iron oxyhydroxide that is the main constituent of rust …   Wiktionary

  • goethite —    A cave mineral FeO(OH) [11] …   Lexicon of Cave and Karst Terminology

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.