- Tantalite
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Tantalite
Tantalite, Pilbara district, AustraliaGeneral Category Oxide minerals Chemical formula (Mg,Fe)(Ta,Nb)2O6 Strunz classification 04.DB.35 Identification Color Dark black, iron-black to dark brown, reddish brow Crystal system Orthorhombic Cleavage Good in one direction Fracture Subconchoidal Mohs scale hardness 6-6.5 Luster Submetallic to almost resinous Streak Brownish-red to black Specific gravity 8.0+ References [1][2] Tantalite, [(Fe,Mn)(Ta,Nb)2O6], is a mineral group that is close to columbite. The two are often grouped together as a semi-singular mineral called coltan or "columbite-tantalite" in many mineral guides. However, tantalite has a much greater specific gravity than columbite (8.0+ compared to columbite's 5.2).[2] Iron-rich tantalite is the mineral tantalite-(Fe) or ferrotantalite and manganese-rich is tantalite-(Mn) or manganotantalite.
Tantalite is also very close to tapiolite. Those minerals have same chemical composition, but different crystal symmetry orthorhombic for tantalite and tetragonal for tapiolite.[3]
Tantalite is black to brown in both color and streak. Manganese rich tantalites can be brown and translucent.
Contents
Occurrence
Tantalite has been found in Egypt, Namibia, Nigeria, Canada, Madagascar, northern Europe, and Maine, California, Colorado and Virginia in the United States. Brazil has the world's largest reserve of tantalite (52.1%).[4] As at 2006, 75% of world tantalite production comes from Australia.[4]
Tantalite is also mined in Guainía and Vichada, Colombia.
Sustainability
The mining of tantalite causes many ecological and social problems in Democratic Republic of Congo.[5][6]
References
- ^ "TANTALITE (Iron Manganese Tantalum Niobium Oxide)". Galleries.com. http://www.galleries.com/Tantalite. Retrieved 2011-10-25.
- ^ a b Tantalite. Mindat.org (2011-09-07). Retrieved on 2011-10-30.
- ^ P. Cerny et al. (1992). "The tantalite-tapiolite gap: natural assemblages versus experimental data". Canadian Mineralogist 30: 587. http://rruff.geo.arizona.edu/doclib/cm/vol30/CM30_587.pdf.
- ^ a b Papp, John F. (2006). "2006 Minerals Yearbook Nb & Ta". US Geological Survey. http://minerals.usgs.gov/minerals/pubs/commodity/niobium/#pubs. Retrieved 2008-06-03.
- ^ Coltan, Gorillas and cellphones. Cellular-news.com (2001-04-03). Retrieved on 2011-10-30.
- ^ The Coltan Scandal. Geology.about.com (2010-07-04). Retrieved on 2011-10-30.
External links
Manganese minerals Borates Carbonates Oxides SimpleMixedBirnessite · Bixbyite · Ferrocolumbite · Ferrotantalite · Galaxite · Jacobsite · Manganotantalite · Psilomelane · Romanèchite · Tantalite · Todorokite · UmberPhosphates Childrenite · Graftonite · Lithiophilite · Natrophilite · Purpurite · Triplite · Triploidite · ZanazziiteSilicates Babingtonite · Bixbite · Braunite · Brownleeite · Calderite · Chloritoid · Eudialyte · Glaucochroite · Jeffersonite · Knebelite · Ottrelite · Piemontite · Pyroxferroite · Rhodonite · Spessartine · Sugilite · Tephroite · Zakharovite · ZircophylliteSulfides Other Axinite (borosilicate) · Geigerite (arsenate) · Manganese nodule (various) · Samsonite (Sulfosalt) · Zincobotryogen (sulfate)This article about a specific oxide mineral is a stub. You can help Wikipedia by expanding it.