Limonite

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Limonite

Limonite is an ore consisting in a mixture of hydrated iron(III) oxide-hydroxide

Iron(III) oxide-hydroxide

A number of species are dubbed iron oxide-hydroxide. These chemicals are oxide-hydroxides of iron, and may occur in anhydrous or hydrated forms....
of varying composition. The generic formula is frequently written as FeO(OH)·nH₂O, although this is not entirely accurate as limonite often contains a varying amount of oxide compared to hydroxide.

Together with hematite

Hematite

Hematite, Spelling differences#Simplification of ae .28.C3.A6.29 and oe .28.C5.93.29 h?matite, is the mineral form of Iron oxide , one of several iron oxides....
, it has been mined

Mining

Mining is the extraction of value minerals or other geology materials from the earth, usually from an ore body, vein or seam. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, Sodium chloride and potash....
as ore

Iron ore

Iron ores are Rock and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in colour from dark grey, bright yellow, deep purple, to rusty red....
for the production of iron

Iron

Iron is a chemical element with the symbol Fe and atomic number 26. Iron is a Group 8 element and period 4 element. Iron is lustrous and silvery in color....
.

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Is Limonite found in Canada? If so, where? Thanks.

Encyclopedia

Limonite is an ore consisting in a mixture of hydrated iron(III) oxide-hydroxide

Iron(III) oxide-hydroxide

Hematite

Hematite, Spelling differences#Simplification of ae .28.C3.A6.29 and oe .28.C5.93.29 h?matite, is the mineral form of Iron oxide , one of several iron oxides....
, it has been mined

Mining

Iron ore

Iron

Iron is a chemical element with the symbol Fe and atomic number 26. Iron is a Group 8 element and period 4 element. Iron is lustrous and silvery in color....
. Limonite is heavy and yellowish-brown. It is a very common amorphous substance though can be tricky to find when mined with hematite and bog ore

Bog iron

Bog iron refers to impure iron deposits that develop in bogs or swamps by the chemical or biochemical oxidation of iron carried in the solutions....
.

It is not a true mineral and it is composed by a mixture of similar hydrate

Hydrate

Hydrate is a term used in inorganic chemistry and organic chemistry to indicate that a substance contains water. The chemical state of the water varies widely between hydrates, some of which were so labeled before their chemical structure was understood....
d iron oxide

Iron oxide

Iron oxides are chemical compounds composed of iron and oxygen. Altogether, there are sixteen known iron oxides and oxyhydroxides....
minerals, mostly goethite

Goethite

Goethite, named after the Germany polymath Johann Wolfgang von Goethe, is an iron bearing oxide mineral found in soil and other low-temperature environments....
with lepidocrocite

Lepidocrocite

Lepidocrocite , also called esmeraldite or hydrohematite, is an iron oxide-hydroxide mineral. Lepidocrocite has an orthorhombic crystal structure, a Mohs scale of mineral hardness of 5, specific gravity of 4, a submetallic Lustre and a yellow-brown streak....
, jarosite

Jarosite

Jarosite is a basic hydrate sulfate of potassium and iron with a chemical formula of KFe362. This mineral is formed in ore deposits by the oxidation of iron sulfides....
, and others. Limonite forms mostly in or near oxidized iron and other metal ore deposits and as sediment

Sediment

Sediment is any particulate matter that can be sediment transport by fluid dynamics, and which eventually is deposited.Sediments are most often transported by water transported by wind and glaciers....
ary beds. Limonite may occur as the cementing material in iron rich sandstone

Sandstone

Sandstone is a sedimentary rock composed mainly of sand-size mineral or rock Particle size . Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust ....
s. Also known as the Lemon Rock.

It is never crystal

Crystal

A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions....
lized into macroscopic crystals, but may have a fibrous or microcrystalline structure, and commonly occurs in concretionary forms or in compact and earthy masses; sometimes mammillary, botryoidal

Botryoidal

A botryoidal texture or mineral Crystal habit is one in which the mineral has a globular external form resembling a bunch of grapes as derived from the Greek language....
, reniform or stalactitic. The colour presents various shades of brown and yellow, and the streak is always brownish, a character which distinguishes it from hematite with a red, or from magnetite with a black streak. It is sometimes called brown hematite or brown iron ore.

Limonite has been known to form pseudomorph

Pseudomorph

In mineralogy, a pseudomorph is a mineral or mineral compound that appears in an untypical form , resulting from a substitution process in which the appearance and dimensions remain constant, but the original mineral is replaced by another....
s after other minerals such as pyrite

Pyrite

The mineral pyrite, or iron pyrite, is an iron sulfide with the chemical formula ironsulfur2. This mineral's metallic Lustre and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold due to its resemblance to gold....
, meaning that the chemical weathering transforms the crystal of pyrite into limonite but keeps the external shape of the pyrite crystal. It has also been formed from other iron oxides, hematite and magnetite; the carbonate siderite

Siderite

Siderite is also the name of a type of iron meteorite.----Siderite is a mineral composed of iron carbonate ironcarbonoxygen3....
and iron rich silicates like some garnet

Garnet

The garnet group includes a group of minerals that have been used since the Bronze Age as gemstones and abrasives. The name "garnet" comes from the Latin language granatus , possibly a reference to the Punica granatum , a plant with red seeds similar in shape, size, and color to some garnet crystals....
s.

It is named from the Greek

Greek language

Greek is an Indo-European languages native to the southern Balkan peninsula, the language of the Greek people. It forms an independent branch within Indo-European....
word for meadow (?e?µ??), in allusion to its occurrence as "bog-ore

Bog iron

Bog iron refers to impure iron deposits that develop in bogs or swamps by the chemical or biochemical oxidation of iron carried in the solutions....
" in meadow

Meadow

A meadow is a field vegetated primarily by grass and other non-woody plants . It may be cut for hay or grazing by livestock such as cattle, sheep or goats....
s and marsh

Marsh

In geography, a marsh, or morass, is a type of wetland which is subject to frequent or continuous flood . Typically the water is shallow and features Poaceaees, Juncaceaees, Phragmites, typhas, Cyperaless, and other herbaceous plants....
es.

The hardness

Mohs scale of mineral hardness

Not to be confused with Siemens_#Mho, a unit of electric conductance.The Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material....
is variable, but generally in the 4 - 5.5 range. The specific gravity

Specific gravity

Specific gravity is defined as the ratio of the density of a given solid or liquid substance to the density of water at a specific temperature and pressure, typically at 4?C and , making it a dimensionless quantity ....
varies from 2.9 to 4.3.

Uses of limonite

In the past bog ore

Bog iron

Bog iron refers to impure iron deposits that develop in bogs or swamps by the chemical or biochemical oxidation of iron carried in the solutions....
or brown iron ore were mined as a source of iron. Iron caps or gossan

Gossan

Gossan is intensely oxidized, weathering or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein. In the classic gossan or iron cap all that remains is iron oxides and quartz often in the form of boxworks, quartz lined cavities retaining the shape of the dissolved ore minerals....
s of siliceous iron oxide typically forms as the result of intensive oxidation of sulfide

Sulfide

The term sulfide refers to several types of chemical compounds containing sulfur in its lowest oxidation number of −2.Formally, "sulfide" is the dianion, S2−, which exists in strongly alkaline aqueous solutions formed from H2S or alkali metal salts such as Li2S, Na2S, and K2...
ore deposits. These gossans were used by prospectors as guides to buried ore. In addition the oxidation of sulfide deposits which contained gold

Gold

Gold is a chemical element with the symbol Au and atomic number 79. It is a highly sought-after precious metal, having been used as money, as a store of value, in jewelry, in sculpture, and for ornamentation since the beginning of recorded history....
mineralization often resulted in the concentration of gold in the iron oxide and quartz of the gossans.

Gold bearing limonite gossans were productively mined in the Shasta County, California

Shasta County, California

Shasta County is a county located in the Northern California portion of the U.S. state of California. The county occupies the northern reaches of the Sacramento Valley, with portions extending into the southern reaches of the Cascade Range....
mining district. Similar deposits were mined near Rio Tinto in Spain

Spain

Spain or the Kingdom of Spain , is a country located in Southern Europe on the Iberian Peninsula.The Spanish constitution does not establish any official denomination of the country, even though Espa?a , Estado espa?ol and Naci?n espa?ola are used interchangeably....
and Mount Morgan

Mount Morgan, Queensland

Mount Morgan is a town located in central Queensland, Australia. It is situated on the Dee River, 38 kilometres south of the city of Rockhampton, Queensland, and is 680 kilometres north of the state capital, Brisbane....
in Australia

Australia

Australia, officially the Commonwealth of Australia, is a country in the southern hemisphere comprising the Australia of the world's smallest continent, the major island of Tasmania, and numerous list of islands of Australia in the Indian Ocean and Pacific Oceans....
. In the Dahlonega gold belt in Lumpkin County, Georgia

Lumpkin County, Georgia

Lumpkin County is a county located in the U.S. state of Georgia . As of the 2000 census, the population was 21,016. The 2007 Census Estimate shows a population of 26,554 ....
gold was mined from limonite rich lateritic

Laterite

Laterite is a surface formation in hot and wet tropical areas which is enriched in iron and aluminium and develops by intensive and long lasting weathering of the underlying parent rock....
or saprolite

Saprolite

Saprolite is the name for a chemically weathering rock. It is mostly soft or friable and commonly retains the structure of the parent rock since it is not transported, but autochthonously formed in place....
soil. The gold of the primary veins was concentrated into the limonites of the deeply weathered rocks. In another example the deeply weathered iron formations of Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is a country in South America. It is the List of countries and outlying territories by total area country by geographical area, occupying nearly half of South America, the List of countries by population country, and the fourth most populous democracy in the world....
served to concentrate gold with the limonite of the resulting soils.

Limonite from occurrences with consistent color is used as the yellow-brown natural earth pigment

Pigment

A pigment is a material that changes the color of light it Reflection as the result of selective color absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which the material itself emits light....
ochre
Ochre

Ochre or Ocher is a color, usually described as Gold -yellow or light yellow brown....
.

Limonite

Uses of limonite

See also

External links