Star Lane's List: Coltan

• The United States does not have a niobium or tantalum mining   industry

• major   producers of niobium mineral concentrates, and Australia,   Brazil, and Canada are the major producers of tantalum mineral   concentrates.

     

• Electronics companies, governments and human rights organizations have been developing methods to prevent the sale of these conflict minerals.
• As part of this effort, scientists are inventing new techniques that could spot the chemical fingerprints of a sample of metal ore and identify its place of origin. Because of its importance to modern electronics and its accessibility in Congo, tantalum is an important metal to be able to trace.
• Tantalum is often found combined with several major and minor components in an ore called coltan, the industry term for a mineral called columbite-tantalite.
• Even when obtaining the ore is not directly connected to the armed groups, the taxing of trading routes can provide them with income. Traders transport the ore out of Congo using a limited number of roads that can support the large shipments -- often travelling through nearby Uganda and Rwanda -- on their way to east African ports. The ore is eventually refined in plants in Asia into forms useful to electronics companies.
• The scientific verification efforts, called fingerprinting, carry an extra advantage, however. If they analyze ore samples before processing takes place, geologists might be able to pinpoint the mine or region from which a sample comes and independently verify its legitimacy.
• Scientists at the BGR -- Germany's Federal Institute of Geosciences and Natural Resources -- began working in 2007 on a two-stage method to find the chemical fingerprint of a piece of tantalum ore and discern its origin. The first stage used custom software and an electron microscope to analyze and identify 10,000-20,000 mineral grains of the product derived from a coltan mine, called an ore concentrate. The second uses a type of laser analysis to zoom in on 50 of those grains, analyze major and minor components, and also the isotopes -- atoms of the same element that contain different numbers of neutrons -- to provide more detail about the age of the sample.
  
• Even if a scientific test could say that a shipment of ore came from within 100 miles of a given point in Congo, Lezhnev said that still might not be good enough. He stressed that the volatility of control of a given area or mine increases the need to resolve the origin down to a small area.
   
   "If you can pinpoint it to a 10 mile radius or a 5 mile radius or something like that, then that's actually helpful," Lezhnev said

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• October 17, 2006
• Tantalum is almost completely immune to chemical reaction at temperatures low temperatures (sub-150 degrees C), and is reactive only with hydrofluoric acid, acidic solutions containing the fluoride ion, and free sulfur trioxide.
• Tantalum is used to make a variety of alloys with desirable properties such as extremely high melting points, extreme strength, good ductility, etc. Tantalum has good "gettering" ability at high temperatures, and tantalum oxide films are stable with good rectifying and dielectric properties.
• Tantalum is used mainly in the manufacture of condensers and micro-electronic technology (chips and processors), cell phones and nuclear reactors.
• The principal modern extraction takes place in Australia, in the Wodgina mine, where the annual production of Ta₂O₅ reaches approximately 150,000 tons.
• The recent technology boom and low availability of COLTAN caused a substantial increase in the price to almost $400 USD per kilogram at one point, as supply struggled to meet the demands of companies such as Nokia and Sony.

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• Mineral Series