Coltan
Coltan is a mineral composed mainly of the minerals columbite and tantalite. Coltan is not a scientific name that corresponds to a specific chemical element. The denomination corresponds to the contraction of the name of two well-known minerals, columbite (COL), niobium oxide with iron and manganese (Fe, Mn)Nb2O< sub>6, and tantalite (TAN), Tantalum oxide with iron and manganese (Fe, Mn)Ta2O6. Coltan is a solid solution between both minerals. That is, both minerals are combined in undefined proportions. Coltan is relatively scarce in nature and is a clear example of materials that have gone from being considered simple mineralogical curiosities to being strategic for technological advancement, due to their applications. The interest in the exploitation of coltan is based fundamentally on being able to extract tantalum; therefore, the value of the coltan will depend on the percentage of tantalite −usually between 20% and 40%− and the percentage of tantalum oxide contained in the tantalite, which can be between 10% and 60%.
As regards the main reserves, there are two totally contrary positions about where the largest coltan reserves are located in the world. The most widespread position is that the largest reserves are in Africa, specifically to the east of the Democratic Republic of Congo (DRC), where 80% of the world's coltan reserves are found. On the other hand, according to a study by the Tantalum-Niobium International Study Center, the world reserves in the DRC would only be around 9% and not 80%. Where they all agree is that Australia, Brazil, Canada, China and some African countries such as the DRC itself, Rwanda, Burundi and Ethiopia are the largest producers of coltan, especially the former. Paradoxically, Rwanda is one of the main producers despite not having coltan reserves. Russia is also rich in this resource, although its deposits have not yet been exploited.
Coltan mining is the cause of geopolitical conflicts, especially in the Congo, where the interests of the state and border countries, guerrillas operating in the region, Western multinationals, and smugglers mix. According to reports from international press agencies and the United Nations, the export of coltan has helped finance various sides in the Second Congo War, a conflict that has resulted in an approximate balance of more than 6 million deaths. Uganda is currently exporting coltan stolen from the Congo to the West, primarily to the United States, where it is used almost exclusively in the manufacture of tantalum electrolytic capacitors.
Uses of coltan
The main application of tantalum is to create capacitors in electronic equipment. The main advantage of this element in capacitors is that it has a high volumetric efficiency, which allows reducing the size of the capacitors, and it has high reliability and stability in a wide temperature range (−55 °C to 125 °C). These characteristics mean that capacitors made of other materials, such as ceramic, cannot match it. Without leaving electronics, tantalum can also be applied to make high-power resistors.
Apart from electronics, the consumption of tantalum has increased in metal alloys, chemical products and carbides. Metal alloys containing tantalum, at levels between 2% and 12%, are used in aircraft engines, in static turbines used to generate power, and in nuclear reactors. It is also used in surgical steel as well as to coat human prostheses, since it is not reactive or irritating to body tissues. In addition, its resistance and its unique physicochemical properties make it privileged as a future material for extraterrestrial use in the Station. Space International and future space platforms and bases.
Inside a smartphone we can find the following applications for tantalum:
- The size of the current batteries has decreased dramatically with respect to the 10-year-old batteries, thanks to the ability of the tantaline to store a high electric charge in very small volumes.
- Tantal oxide serves to produce thinner and smaller chamber lenses.
- Tantalo helps to maintain highly-driven materials under control and helps signals to quickly pass through the device.
- The microprocessor also possesses tantalo, as it acts as a barrier to maintaining the integrity of the transistors within the chip itself.
As for niobium, it is used in metallic alloys with applications in aeronautics, although it has another very interesting property, superconductivity, which makes it possible to create very powerful electromagnets that are used in magnetic resonance devices and particle accelerators.
Production
In 2008, approximately 71% of the world's supply of tantalum came from freshly mined material, 20% from recycled material, and the rest from tin slag and inventory. The main producers as of 2009 of coltan were Australia, Brazil, Canada, the Democratic Republic of the Congo and other African countries. Tantalum is also produced in Thailand and Malaysia, though not from coltan, but from a tin by-product.
Other countries, such as Saudi Arabia, Egypt, Uganda, Greenland, China, Mozambique, the United Kingdom, Finland or Afghanistan, could start exploiting future mines if their prospecting for coltan prospers. In 2009, the governments of Colombia and Venezuela announced the discovery of significant coltan reserves. In May 2018, Venezuela made its first export of this composite mineral to Italy consisting of 10 pallets with a total weight of 5 tons and a value of 300,000 euros. In 2020, after a study of six years of work by the CSIC, the formula for obtaining coltan from the Penouta mine in the Orense municipality of Viana del Bollo, in Spain, was completed.
According to the United States Geological Survey (USGS), world production of coltan was, in 2013, 590 metric tons of mined tantalum, with Rwanda (150 t) as the largest producer, followed by Brazil (140 t)., the Democratic Republic of the Congo (110 t) and Canada (50 t). According to the USGS itself, the peak of production worldwide occurred in 2002 with 1,470 metric tons mined. The agency did not include China, Kazakhstan and Russia in its estimates due to the scarcity and uncertainty of the data, despite the fact that these countries have significantly increased the demand for this material in recent years.
Between 1990 and 2009, Australia was indisputably the world's largest producer of coltan, with a production quota that reached 75.9% (1995), however this country reached its peak production in 2002, with some 940 metric tons mined, and in 2009 its production was less than 10% (81 t) of the 2002 production, production that in 2012 and 2013 dropped to zero. Brazil has been the second largest producer since 1990 —with peak production in 1998, 310 metric tons mined—, although unlike Australia it has maintained a stable, albeit declining, amount of production. During the 1990s, Canada was the third largest producer, although since the XXI century it has been surpassed, with few exceptions, by the Republic Congo, which, with ups and downs, has been increasing its production up to 110 metric tons mined in 2013 (estimates), which meant around 19% of world coltan production. These figures are probably notably higher, Due to the fact that countries bordering the Congo, such as Uganda or Rwanda, annually steal significant quantities of coltan from the country, which they export as if it had been extracted in their territories.
| Coltan World Reserves (in tons) | |
|---|---|
| Brazil | 87 000 |
| Australia | 40 500 |
| China | 7500 |
| Congo | 3500 |
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Increasing prices and changing demand
There has been a significant drop in the production and sale of coltan and niobium from African mines since there was a drastic price increase in 2000, due to speculation in so-called .com companies and the big orders. This is confirmed in part by figures from the United States Geological Survey.
The International Tantalum-Niobium Study Center in Belgium (a country with traditional ties to the Congo), has advised international buyers to avoid coltan from the Congo region on ethical grounds and to crack down on illegal smuggling of the Central African regions to avoid continuing to finance the guerrillas.
"The Central African countries of the Democratic Republic of the Congo and Rwanda and their neighbours used to be the source of significant tonnages. But civil war, plundering national parks and exporting minerals, diamonds and other natural resources to finance militias has forced the International Tantalio-Niobio Study Centre to call its members to be careful to obtain raw materials from legal sources. The damage, or the danger of causing harm, to the local population, wildlife or the environment is unacceptable. "
A normal Congolese worker earns around $10 per month. A worker who works in the mines extracting coltan earns between $10 and $50 a week. A ton of coltan is quoted in the market at $400,000. The extraction method is archaic, it is very similar to the method used to extract gold in the US in the past. They work in semi-slavery conditions. A good worker can get a kilo of coltan daily. In addition to coltan, other radioactive minerals with similar characteristics appear, elements such as uranium, thorium and radium, among others. Due to workers' exposure to these minerals, there have been a large number of radiation sickness.
However, one can also see a shift for economic rather than ethical reasons, from traditional sources like Australia to new suppliers like Egypt. This could have led to the bankruptcy of one of the world's largest suppliers, Australia's Sons of Gwalia Ltd., although the company continues to produce and export ore.
At an economic level, there are certain multinationals that, as large buyers of this mineral, are not interested in the social conflicts derived from the extraction of the mineral being published in the media. The latter, in turn, are conditioned by the fear of losing significant advertising revenue.
Problems
The Democratic Republic of Congo holds 80% of the world's estimated coltan reserves, according to majority opinion. As this mineral is considered a highly strategic non-renewable resource, there has been a war in the Congo since 1998 for control of the deposits. According to the United Nations, the Rwandan Defense Forces have set up a structure to monitor mining activity in the Congo and facilitate contacts with Western businessmen and clients. It transports the ore to Rwanda where it is processed before being exported. The final recipients are the United States, Germany, the Netherlands, Belgium and Kazakhstan. This war, directly related to the exploitation of this mineral, has resulted in a balance of more than 5.5 million victims, which is the highest number of deaths since World War II.[citation required]Coltan forms part of what is known as conflict minerals. The four most common conflict minerals known as the 3TG for the acronym of the minerals in English: tin (cassiterite), tungsten (wolframite), tantalum (coltan) and gold (gold ore).
Rwanda and Uganda have been accused in various international reports of pillaging and trafficking these mineral wealth from the Congo. With several Western countries being the main beneficiaries, economic and military aid continues during the conflict. Support and cooperation plans were signed between the United States and these two countries, which, in addition to enriching themselves with mineral trafficking, saw part of their external debts canceled and were considered models of economic development in the region. Among the most important companies with interests in the region, the American Mineral Fields has been mentioned, in which George H. W. Bush, former president and father of also former US president George W. Bush, has notable interests. Two sides fought the war: on the one hand Rwanda, Uganda and Burundi, supported by the US and IMF and World Bank credits, and on the other side Angola, Namibia, Zimbabwe, Chad and the Hutu and Mai-Mai militias.
The exploitation of coltan, especially in Congo, has caused various controversies about the possible consequences at a social and environmental level. The exploitation of this resource has fueled armed conflicts between local factions, supported, in some cases, by foreign governments such as that of Uganda. This poses a moral dilemma similar to that of the trade in war diamonds. Other concerns derived from the extraction of coltan go through the labor exploitation of the workers who participate in it or the destruction of ecosystems, since the main deposits coincide with the habitats of endangered gorillas.
The forms of mineral extraction, such as Barequeo (manual digging of holes) and Levigation, carried out by workers from the DRC, Brazil, China are very harmful to health, since they do not have the conditions ideal for its operation nor with the necessary security to be able to handle this mineral with a high level of radioactive contamination.
But not only people suffer, but also the environment, since Coltan is mined in the open sky, which is why thousands of hectares of forest have been exploited for this resource. According to Greenpeace, these 100 million hectares of African jungle are home to 70% of the continent's fresh water and are home to 8% of the planet's carbon reserves, so their disappearance would release 34,400 million tons of carbon dioxide into the Earth. atmosphere.
The Rwandan occupation of eastern Congo has meant that the Democratic Republic of Congo has been unable to exploit this resource for its own benefit. A recent United Nations Security Council report has reported that a large amount of this mineral is being illegally mined and smuggled across the borders by militias from neighboring Uganda, Burundi and Rwanda. It is estimated that the Rwandan army has made a profit of around 250 million dollars in about 18 months of selling coltan. These estimates are difficult to verify, however, as Rwanda has its own coltan deposits, making smuggled ore difficult to identify.
Coltan smuggling has also been identified as the largest source of income for the military occupation of Congo. Due to mounting public pressure, some electronics manufacturers have decided to set aside this area of the world as a source of coltan, and turn to other sources.
The governments of the three countries identified by the United Nations as coltan smugglers have denied involvement. Austrian journalist Klaus Werner has documented the links between multinational companies and illegal trafficking, as these companies finance the guerillas that traffic in coltan.
Properties
Coltan is widely used due to the following properties:
● It has a great resistance to heat, even better than iron, it supports very high temperatures.
● It has a great capacity to store electrical charges.
● It has a high resistance to the deterioration of a material due to a change in its environment, that is, against corrosion.
● High resistance to wear, this is due to its unique properties, such as superconductivity, ultra-refractory character (minerals capable of withstanding very high temperatures), being a capacitor (it stores temporary electrical charge and releases it when needed).
● It is a better conductor than copper, since the fusion of the minerals columbite and tantalite has characteristics that make it essential for the creation of electronic devices: it does not rust, and this makes it an 80% better conductor of electricity than copper and is capable of storing a lot of charge that it releases slowly.
Beneficiaries
The outbreak of violence, which world and African leaders are now trying to contain, took place at the end of August, when the rebel Congolese general Laurent Nkunda advanced with his troops through the North Kivu region.
The leader of the National Congress for the Defense of the People says he is acting because his ethnic group, the Tutsi minority, has been excluded from the democratization process. This process led to the holding of the first elections in history in July 2006, which ratified Laurent-Désirè Kabila as president.
Nevertheless, Nkunda himself has declared other objectives of his uprising, demanding to negotiate directly with Kabila on an important agreement that his government reached with China to exploit the mineral resources of the area. With the sale of the minerals, the rebels obtain large sums of money to arm and equip their guerrillas, which makes it difficult to disarm these groups, agreed a year ago.
General Nkunda, accused by international justice of committing war crimes, considers himself a man of God, and claims to have expressly asked his militiamen to avoid getting into the business of the minerals. Despite the fact that he denies having any relationship with coltan, he claims to control all the economic performance of the region, with the excuse of obtaining food, raw materials and weapons, necessary to sustain the rebel movement and thus continue his fight for full recognition. of the rights of the Tutsis.
Without leaving Africa, it is also worth mentioning the role of the Olive Group, a coltan supplier company, which ensures that the demand for the mineral abroad is so great that they cannot fully satisfy it. This indicates that there is no boycott by the West of this type of business.
One of Live's best clients is the Belgian company TRAXYS, specialized in rare minerals and named in a 2003 UN report as one of the entities dedicated to financing conflicts in the Congo. This company ensures that it maintains its own control measures over the merchandise, materialized in the sending of independent teams that are in charge of verifying the version of the suppliers, and affirms that the coltan that arrives to them does not come from the war zones.
Companies such as TRAXIS export coltan to the entire world and especially to China, where half of the mobile phones that circulate annually around the planet are produced. The big international brands (Apple, Samsung, Motorola, Nokia, etc.) subcontract part of their production there, knowing that the mineral comes irregularly from Africa.
Faced with this situation, mobile phone companies have multiplied their communication campaigns, where they demand that their suppliers not buy coltan in the Congo. Nokia's own president, when asked about this, replied that they have always been careful with the environment.
A material discovered relatively recently is graphene. Although it was synthesized for the first time in 2004, it did not rise to fame until 2010, when researchers Andrey Gueim and Konstantin Novosiolov received the Nobel Prize in physics. It is still too early to say whether graphene will replace coltan, but among the many properties that this material has, some that are interesting for our case are that it has the ability to self-cool, it conducts electricity better than any other known metal, and it is very resistant, abundant and economical. All these properties will make it possible to create much more durable batteries. Ultracapacitors will be created that can be ten times more durable and charge in much less time. According to forecasts, this can be commercialized in the next five or ten years, therefore, the main application of tantalum can also be carried out with graphene.
Coltan in Argentina
Since April 2012, there has been a growing interest in the exploitation of the mineral in Argentine territory, a fact confirmed from the center of GEMERA - Group of Mining and Exploring Companies of the Argentine Republic - where they affirm that the State knows the existence of local metal reserves since the 1970s, and that proposals for the coming decades were already being discussed in the sector. For its part, SEGEMAR –Argentine Mining Geological Service– pointed out the presence of this mineral in the areas of the provinces of Córdoba (reservoirs were detected in the Calamuchita Valley and in the Sierras de los Comechingones), San Luis and Salta, and signs of it in Catamarca and La Rioja. Coltan is found in rock basements between 200 and 600 million years old, which is why there may be the possibility that it is also found in the northern areas of Cuyo, as well as in Santiago del Estero, and in elevations and massifs of Tucumán.
Although coltan was present in old mining exploration programs (and even in the 70s they were evaluating how to extract it), with the passage of time and the successive changes of government, interest decreased.
On the other hand, coltan is part of an ambitious political proposal by the European Union, in agreement with Mercosur, to take away the determining power of minerals from the Chinese nation (since it owns 90% of the supply worldwide), defending itself under the standards of the impact generated by the extraction of coltan along with another layer of minerals, popularly called rare earths, located in areas, such as the Congo. There are many illegalities there, which brings with it a great repercussion for the violation of human rights, which puts at stake the reputation not only of governments, but also of large companies that make use of these materials for the creation of new technologies. For this reason, it would be replaced by the idea of extracting these minerals in other conflict-free zones, far from the African continent, focusing on South American territory where their existence is being verified, with Argentina forming part of the key points. extraction throughout its territory. However, according to the latest research from international environmental organizations, the environmental danger of the practice of extracting coltan and rare earths reaches scales of repercussions both in water (due to its excessive use) and in soils (generating great contamination)., noting that the latter directly includes coltan and its practices to obtain it.