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Coltan mining

August 13, 2010

Researchers say they have come up with a new way to prove where coltan samples came from. That could allow companies and refineries to purchase African coltan knowing that it did not come from a conflict area.

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coltan ore
Tantalum is exctracted from coltan oreImage: cc-nando.quintana-sa

In the late 1990s and early 2000s the world began to wake up to the reality of "blood diamonds," or diamonds mined in regions of sub-Saharan Africa used to fund violent conflicts, especially in Liberia, Angola and Sierra Leone.

But over the last decade, activists, scientists, and politicians have also been made increasingly aware of the use of coltan mining to fund similar conflicts central Africa, especially in the Democratic Republic of Congo (DRC).

In 2009, German mineral authorities said that Africa produced half of the world's coltan, significantly up from previous years as major mines in Canada and Australia were shut down due to coltan's falling price. The metallic ore contains tantalum, a key element in the production of semi-conductors and capacitors found in nearly every consumer electronic device, including iPods, mobile phones and video game consoles.

A study released in May by the London-based Resource Consulting Services (RCS) said that in 2009, a group of Hutu rebels in Rwanda, the Democratic Forces for the Liberation of Rwanda, were 75 percent funded by the sale of minerals like coltan.

The Masisi region in eastern Congo contain important deposit of coltan
The Masisi region in eastern Congo contain important deposit of coltanImage: AP

But governments worldwide are starting to take action. US President Barack Obama recently signed into law a provision requiring more transparency in the mineral mining sector. The European Union does not currently have any similar provisions.

The American law will require companies sourcing coltan from the DRC and its nine neighboring countries, including Rwanda, to prove that their mineral exports are conflict-free. Some development activists have said that while this is a positive development, turning the new law into an effective embargo may be a nearly impossible task.

But in recent years, German scientists have said that they have found a method of chemical analysis to determine which coltan samples are conflict-free. They said each coltan sample from a particular mine has a given "fingerprint," or unique set of characteristics.

'It's a totally different mineralogy'

From his office at the Federal Institute for Geosciences and Natural Resources in Hannover, Frank Melcher has a collection of rock cuttings in small see-through boxes and plastic bags spread out. Next to each box and bag he puts a color print-out of pictures taken with an electron microscope. To the untrained eye they look like pictures of mosaic floor, but for Melcher they indicate far more.

"If you compare coltan samples from different proveniences, it's quite obvious," he said. "This is a sample from Rwanda, this one's from Australia. The dye distribution is totally different. It's a totally different mineralogy."

Dr. Frank Melcher
Melcher examines the origin of coltanImage: BGR

Melcher is one of many German scientists working to set up a "certified trading chain," which would establish the origin of coltan samples.

He relies on more than using visual cues to identify a coltan sample's provenance. Melcher and his colleagues also use an electron microprobe that hits the sample with an electron beam. The emerging x-rays indicate which chemical elements are contained in the sample.

"I can see right away what elements are contained in this sample and how much of them," he said. "Here it's tantalum, there it's niobium, manganese, iron and I spot some titanium as well."

German government scientists are using this technique to register the fingerprints of legitimate mines that then could be compared to field samples mined in the future. The idea would be to provide incontrovertible evidence showing that a sample of coltan was mined in a conflict-free zone. Melcher said he has reference samples from 75 percent of the world's coltan mines.

"We hope that one day only truly clean products leave African soil," he said.

"In connection with environmental and social standards this could be the way to go for raw materials," he added. "We want a trading chain with European and American companies purchasing goods directly from the African market. This is impossible for them at the moment."

However, samples from mines in China and the DRC comprise the remaining 25 percent, he added.

"The Chinese aren't interested in delivering samples, and DRC is impossible to access," he said.

European refineries stand to benefit

A coltan mine in Mozambique
The German process could limit coltan mining to conflict-free regionsImage: BGR

Some German companies have already been affected by the shadiness of the coltan trade. H.C. Starck, based in the central German city of Goslar, has one of the many refineries around Europe that takes coltan ore and refines it into pure tantalum.

H.C. Starck is one of the few companies capable of completing the complex process of making tiny, reliable and heat-resistant capacitors out of tantalum. But 10 years ago the United Nations accused the company of using tantalum from war-torn regions of Congo and H.C. Starck's reputation suffered significantly.

After the accusations became public, the company began cooperating with the United Nations and re-evaluated its coltan acquisition process. Starck now does not purchase any tantalum from Africa.

"While working through everything together with the UN panel, we found out, that not every retailer had told us the truth concerning the material's origin - despite assuring otherwise," said Manfred Buetefisch, a company spokesperson. "That's when we realized that - seeing the ongoing war in East Africa and the DRC - that they are not reliable partners for us, and that we cannot buy any material there anymore."

Companies like H.C. Stark are now banking on being able to rely more and more on African coltan. The company already bought a NRD Rwanda, a small mining company in Rwanda. Soon, every one of its deliveries will be certified by the Federal Institute for Geosciences and Natural Resources in Hannover.

Rock cuttings for the license have already been already charted and included in Frank Melcher's database. By taking random control samples the geologist can now verify whether coltan was taken from the company's mine in Rwanda.

"This is of course an ideal case: a company investing in the local mining industry, importing the coltan on its own and making sure that it is no illegally mined material infecting the trading chain," Melcher said.

Certification is slow moving

A man's hands separate coltan ore from other rocks
Coltan is often separated from other rocks by handImage: BGR

One year ago the Federal Institute for Geosciences and Natural Resources invited all 10 Rwandan mining companies for a certification workshop. The companies' chief executives were reserved in the beginning but four companies joined NRD Rwanda and have signed up for the testing procedures.

Industry analysts have said that the new practice may pressure African coltan-exporting countries to clean up their mining practices on their own, without relying on harsher external policies.

"This might limit corruption, violence and other conflicts fought over coltan and other resources," said Peter Eigen of the NGO Transparency International. "Once the companies voluntarily agree to cooperate, it's easier to make a point rather than trying to boycott these raw materials or subject them to certain conditions."

But first, the Hannover geologists have to adapt their methods to the industry in the Congo. And they all know that it's a far cry from the way things work in Rwanda to the unstable situation in the Democratic Republic of the Congo.

While German scientists say getting Congo and China to adopt their methods will be difficult, they said they are confident their process change coltan mining in the long term. While they are willing to provide the fingerprinting system, they say that the certification chain must be located in Africa to be most effective, and that its implementation remains a local political issue.

"There will be a big meeting in Nairobi before the end of the year for certification procedures," Melcher said. "We hope that fingerprinting will be part of the measures that they take."

Author: Jan Lublinski / Monika Griebeler / Cyrus Farivar

Editor: Sean Sinico