Goethite


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Related to Goethite: limonite

goethite

[′gə‚tīt]
(mineralogy)
FeO(OH) A yellow, red, or dark-brown mineral crystallizing in the orthorhombic system, although it is usually found in radiating fibrous aggregates; a common constituent of natural rust or limonite. Also known as xanthosiderite.

Goethite

 

(named in honor of the poet J. W. Goethe), a mineral of the iron hydroxide group; chemical composition FeOOH. It contains admixtures of manganese and aluminum, as well as surplus adsorbed water (hydrogoethite). The mineral crystallizes in a rhombic system, forming columnar, needle-like crystals and their growths, sinter aggregates, and powdery and earthy masses mixed with hydrogoethite, hydrohematite, and other minerals (so-called limonites and bog iron ores). The color is brownish yellow to dark reddish brown. Needlelike crystals of goethite gathered into bundles are called needle ironstone. The hardness of goethite on the mineralogical scale is 5-5.5; density, 4,140-4,280 kg/m3. Goethite in crystals sprouting quartz, together with iron sulfides and other sulfides, is found in hydrothermal deposits, which are numerous in the USSR and abroad. The widest distribution of goethite in nature is associated with supergene and sedimentary deposits of iron ores.

G. P. BARSANOV

References in periodicals archive ?
Sibanda HM, Young SD (1986) Competitive adsorption of humus acids and phosphate on goethite, gibbsite and two tropical soils.
Features such as marked quartz etching, replacement of hematite by goethite, and high A1 substitution of goethite and hematite in these nodules are consistent with strong chemical weathering (Schwertmann and Carlson 1994).
Fendorf S, Eick MJ, Grossl P, Sparks DL (1997) Arsenate and chromate retention mechanisms on goethite.
This agrees with the findings of MeKenzie (1980) that Cr is more bound to goethite and hematite than to other clay minerals.
The matrix (50 vol%) is composed of gibbsite septa (boxwork) and iron oxide accumulations which consist mostly of goethite.
The mineralisation occurs as massive hematite and goethite enrichment within the BIF and is most likely to result of a mixture of hypogene and supergene enrichment.
Torrent J, Schwenmann U, Barron V (1987) The reductive dissolution of synthetic goethite and hematite in dithionite.
The haematite and goethite occurrences are interpreted to result from alteration and enrichment of the magnetite-bearing BIF, particularly in areas of complex folding.
Calcite, quartz, kaolinite, and apatite make up the major mineral components of the Lajjun oil shale, along with small amounts of dolomite, feldspars, pyrite, illite, goethite, and gypsum [4].
In Grand Pre, the filtrate colour suggests that goethite and hematite precipitated.
It is worth mentioning that the presence of iron oxide and hydroxide group minerals, specifically goethite was very low or absent in sampling site 1, 7 and 20.
3]), possibly goethite ([alpha]-FeOOH), and other compounds [3, 17-21].