Coltan, also as „black gold “designation, is a raw ore in Central Africa, from which the metal tantalum ( TA) is won with priority. The name „Coltan “leads itself from the group of minerals of Col umbit Tan talit off.

Also the way of writing “Koltan” is common.

The chemical composition of theseGroup of minerals is however very variable: Like that the pure metallic oxides Niobit to regard (= columbite) and Tantalit are as stops of a natural mixture row of the general chemical formula (Fe, Mn) (Nb, TA, self-service) 2 O 6. Under the many Varietäten only the iron-rich mineral is Ferrotantalit and/or. Ferroniobit and thatantimony-rich Stibiotantalit and/or. Stibioniobit mentions. Primarily to crystalline rocks, among other things bound to alkali Pegmatit courses, these minerals are frequently also on secondary stores like e.g. in heavy mineral soaps.

Thus local win diggers “(“creuseurs “) from the soil by wet sieving and weight separation concentrates for the further in the Coltan mines of Central Africa „Smelting. The peak values in these concentrates are with 40 45% “Tantalit” (tantalum oxide TA 2 O 5).

The Coltan dismantling of Central Africa essentially concentrates on the Kigali - and Kivu - region (border area of the democratic Republic of the Congo to Rwanda).

Further important tantalum niobium stores are in Brazil, Canada and west Australia.


the metal tantalum is used variously because of its high temperature and corrosion resistance in the industry, among other things for the production of surgical instruments and in the high vacuum technology. For some years it becomes also in the modernMicroelectronics for the production of smallest condensers related to high electrical capacity. Examples are mobile telephones, laptops as well as military High carouse products such as guidance rockets etc.

In December 2000 the high demand for such devices led to a multiplication of the world price for tantalum (480 Dollar/kg), occasional even thatPrice for silver exceeded. Afterwards the price oscillated itself and reached in the spring 2005 a value of <80 Dollar/kg.

The high profits and the national monitoring lacking during the civil war in the democratic Republic of the Congo led to completely unmethodical mining industry activities. Serious environmental damage was the consequence. Among other things larger surfaces of the already strongly reduced habitat of the gorillas were destroyed.

At the same time the incomes from the mining industry and unsatisfactorily controlled embargoes made the local Milizführern possible (above all rebel of the RCD - “Rassemblement Congolais pour la Démocratie” - “Congolese collection for democracy”)the payment of soldiers, the purchase of weapons and the continuation of the civil war.


the metal niobium (Nb) is chemically closely related to tantalum. So is it z.Zt. more expensive tantalum with the production of condensers replace. It becomes likewise the metallurgicalProduction of hard and heatproof alloys (superalloys) for gas turbines and rocket parts uses.

Main supplier of the niobium is portions of further cations (TA, Ti, approx., changing the iron-poor mineral Pyrochlor, that beside Nb, well etc.…) contains. It is diminished with Lueshe in the Kivu region.

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