Hematite, also spelled as haematite is the mineral form of iron(III) oxide (Fe2O3), one of several...
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Transcript of Hematite, also spelled as haematite is the mineral form of iron(III) oxide (Fe2O3), one of several...
Hematite, also spelled as haematite is the mineral form of iron(III) oxide (Fe2O3), one of several iron oxides.
Huge deposits of hematite are found in banded iron formations. Gray hematite is typically found in places where there has been standing water or mineral hot springs, such as those in Yellowstone National Park in North America. The mineral can precipitate out of water and collect in layers at the bottom of a lake, spring, or other standing water.
Category Oxide minerals
Formula Fe2O3
Color Metallic gray, dull to bright red
Crystal habit Tabular to thick crystals; micaceous or platy, commonly in rosettes;
Specific gravity 5.26
Mohs scale hardness 5.5–6.5
Optical properties Uniaxial
Crystal system Trigonal
Tenacity Brittle
Luster Metallic to splendent
Cleavage None, may show partings on {0001} and {1011}
• Hematite is a mineral, colored black to steel or silver-gray, brown to reddish brown, or red. It is mined as the main ore of iron and it has the same crystal structure as ilmenite and corundum• Hematite is harder than pure iron, but much more brittle
•Hematite is an antiferromagnetic material below the -9.7 degrees Fahrenheit (°F), and a canted antiferromagnet or weakly ferromagnetic above the Morin transition and below its Néel temperature at 948 K, above which it is paramagnetic.
Hematite's popularity in jewelry was at its highest in Europe during the Victorian era.Certain types of hematite or iron oxide-rich clay, especially Armenian bole, have been used in gilding. Hematite is also used in art such as in the creation of intaglio engraved gems. Hematine is a synthetic material sold as magnetic hematite
Hematite is present in the waste tailings of iron mines. A recently developed process, magnetation, uses magnets to glean waste hematite from old mine tailings in Minnesota's vast Mesabi Range iron district. Falu red is a pigment used in traditional Swedish house paints. Originally, it was made from tailings of the Falu mine.
Bibliography
http://en.wikipedia.org/wiki/Hematite
http://www.mindat.org/min-1856.html
http://en.wikipedia.org/wiki/Hematite#mediaviewer/File:WLA_hmns_Hematite.jpg
http://www.baidu.com/link?url=nbGWZ5ZiYHT9DG-pkNLSrlZihonuEpEkR9t3_GSWzeR0TwboymvChjnyCOb6m6Ne&wd=hematite&ie=utf-8&f=8&tn=baidu