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3TG Tin Tungsten Tantalum Gold

Conflict minerals are applicated by the armed groups and units in Democratic Republic of Congo in Africa to financed to buy guns or support their compaigns. The minerals are have no emotion. They were given emotion value when they were fighted for. Commenly, the more intense fighting, the higher the value.

The fighting in Democratic Republic of Congo has continued over 15 years,driven by the illegal trade in valueable minerals.

In the Congo there are four main types of minerals being explored, which are shorted into 3TG:

*Cassiterite——Tin ore——Tin;

*Coltan——The ore containing a rare metal called tantalum——Tantalum;

*Wolframe——The ore for tungsten——Tungsten;

*Gold ore——Gold;

Brief introduction of 3TG:

Tungsten:
Tungsten is the names given to element 74 of Mendeleev's Periodic Chart of the Elements. Its chemical symbol is W. Tungsten features the lowest vapour pressure of all metals, very high moduli of compression and elasticity, very high thermal creep resistance and high thermal and electrical conductivity. Tungsten is the most important metal for thermoemission applications, not only because of its high electron emissivity (which is caused by additions of foreigh elements) but bacause of high thermal and chemical stability.

The primary uses of tungsten are: hardmetals, also named cemented caribides, are the most important usage of tungsten. Tungsten improves steel properties. Other applications include a widespread variety of chemical uses.

Tantalum:
Tantalum is the named given to element 73 of Mendeleev's Periodic Chart of the Elements. Its chemical symbol is Ta. Tantalum is also known as tantalium. Tantalum is a rare, hard, blue-gray, lustrous transition metal.Tantalum is widely used as minor components in alloys and used in tantalum capacitors in electronic equipment.

Tin:
Tin is the named given to element 50 of Mendeleev's Periodic Chart of the elements. Its chemical symbol is Sn.Tin is obtained chiefly from themineralcassiterite, where it occurs as tin dioxide, SnO2. Tin is used to coat other metals to prevent corrosion. Because of its low toxicity, tin-plated metal is also used for food packaging, giving the name to tin cans, which are made mostly of steel.

Gold:
Gold is the named given to element 79 of Mendeleev's Periodic Chart of the elements. Its chemical symbol is Au. Gold appearances bright yellow luster. It maintain stable in air or water. Gold traditionally considered attractive and valueable.

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