[pull_quote_center]Various African countries have huge deposits of heavy minerals with South Africa being the second largest producer of titanium and zircon in the world after Australia. [/pull_quote_center]
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Africa is a continent richly endowed with a variety of economically viable mineral deposits. The continued discoveries of these mineral deposits have made the continent a beehive of activity in the recent past with multinational mining companies seeking to have a piece of the pie.
Heavy Minerals Mining is one of the numerous exploration activities currently being undertaken on the continent. They are called heavy minerals because they have a density greater than 2.9 g/cm3. 75 percent of the world’s titanium is produced from heavy mineral sands. Various African countries have huge deposits of this mineral with South Africa being the second largest producer of titanium and zircon in the world after Australia.
Kenya will see its first bulk shipment of titanium minerals come online in January 2014 from Base Titanium’s Kwale project while other countries like Namibia, Mozambique, Senegal, Tanzania, Sierra Leone, Gambia and Mauritania also have heavy mineral potential.
Heavy mineral sands are an accumulation of valuable minerals, normally called placer deposits, formed by gravity separation during sedimentary processes.
Upon depositing of sand on the coastline by waves heavy minerals are concentrated as backwash carries some of the lighter minerals back to sea. Onshore winds which preferentially blow lighter grains inland sometimes lead to higher concentrations of heavy minerals at the front of coastal dunes and as a result strandlines, old fossil shorelines, can now be found a little distance inland. Heavy mineral sands are an important source of titanium, rare earth elements, thorium, zirconium and tungsten and industrial minerals such as diamond, sapphire, garnet and occasionally gemstones.
Application
Heavy minerals have vital economic applications. Even though the strength and chemical inertness of titanium allows it to be used in defense, medical and aerospace industries more than 95 per cent of total titanium supply is for pigment production. Zircon is used in TV screens due to its ability to absorb X-rays. Its hardness, high melting point and low expansion coefficient when heated enables it to be used in foundry sand and as an abrasive.
It is also used as a source of zirconia for the chemical industry in adhesives, antiperspirants, catalysts, aqueous polymers, gelatin hardening and dyes. Zircon is also used mostly in the ceramics industry to glaze finishes of tiles, crockery and bathware for durability and resistance to discoloration.
As a metal Zirconium is fairly soft, malleable and easily worked. Its high density and high melting point makes it suitable to be used in modern superconductors. The oxide is also used in fuel cells, transducers in audio equipment and oxygen sensors. In the paper coating industry, Zr-carbonate acts as an insolubilizer while in textiles potassium hexafluorozirconate acts as a flame retardant.
Global Mining locations
Presently heavy minerals are mined in Australia, China, India, sub Saharan Africa and South America. Australia is the largest producer as well as world’s leader in protecting coastlines by redeveloping them.
Figures from the Geoscience Australia and the United States Geological Survey data show that Australia’s Economic Demonstrated Resources (EDR) of rutile and zircon in 2012 was the world’s largest economic resources with 52 percent and 53 percent respectively.
Australia also has the second largest share of the world’s ilmenite with 15 percent behind China which has 31 percent. India has 13 percent, South Africa 10 percent and Brazil with 7 percent. South Africa leads with 16 percent and 24 percent of rutile and zircon respectively followed by India at 15 percent and 6 percent in that order.
Base Titanium’s Kwale mineral sands project in Kenya which began production in October 2013 will produce 330,000 tonnes of ilmenite, 14 percent of the world’s rutile output or 80,000 tonnes and 30,000 tonnes of zircon annually over a 13-year mine-life.
In Africa, Anglo American and BHP Billiton stand out as the main producers of heavy minerals from their operation on both coasts of South Africa. Zircon and Rutile are the main minerals mined at Anglo American’s Namakwa Sands on the West Coast North of Cape Town. In northeast South Africa BHP Billiton has a 50 percent share with Rio Tinto in Richards Bay Minerals (RBM). BHP Billiton is further pursuing its TiGen project in Mozambique with Rio Tinto also having potential deposit in Madagascar.
Sierra Leone used to be one of the world’s largest zircon producers but political instability stopped mining operations in 1995. As of December 2011, Kenmare’s Moma mine in Mozambique had a reserve of around 26mt of ilmenite, 1.8mt of zircon and 0.55mt of rutile.
Benefits
Heavy mineral mining has both economic and social benefits to the host countries. Mining of these minerals creates employment for thousands of citizenry.
This significantly improves the social status of the people in the third world countries. It also leads to development of various infrastructure projects such as roads, ports, dams e.t.c. An ideal example of how these mining activities can benefit the local people and play an important role in advancing the national economy well beyond the life of the mining operation is Base’s Kwale project in Kenya.
Key infrastructure developed for the project to be handed over to local authorities on decommissioning of the mine will have a significant influence on socio-economic factors in the region. The Mukurumudzi Dam and Msambweni boreholes will contribute enormously to the regions irrigation and water supply requirements.
The Project’s 132kV transmission line represents a further step to realising the targets to establish the East Africa Power Pool. The 8km mine access road will assist with links from the current Mombasa – Tanzania highway to roads planned in the future further inland and the project’s port facility will be an important contributor to Likoni’s industrial development.
The project will contribute over US$220 million to the Government of Kenya in direct tax and royalty payments over the 13 year life of the mine and it is the flagship of the mining sector leading the way in developing Kenya’s mineral potential as a significant contributor to the socio-economic development of the country.
The mining activities also contribute significantly to the economies of countries endowed with the minerals by generating significant export and direct government revenues. Such countries also benefit from direct tax and royalty payments.
Despite all the benefits mentioned above, mining of these minerals have attracted controversies. Since most of the heavy mineral activities take place in beach environments, the operations require the strip mining of large areas. Most of the land explored is ecologically sensitive and contains fragile ecosystems built up on poor sandy soils.
This is coupled by lack of rehabilitation of the mined areas. This has seen various environmental concerns raised in the past as in the case of the Tuart-Ludlow mineral sands mine in Western Australia and the culmination of conservationist efforts to preserve Rainbow Beach and Fraser Island in Queensland, Australia.
Environmental activism has succeeded in the past successfully lobbying governments to safeguard and redevelop mined areas. A perfect example is in Australia which saw Fraser Island and Rainbow Beach protected by the High Court of Australia. Even though not all, some South African mines do practice dune rehabilitation.
South America especially Chile and Ecuador carry out heavy mineral mining activities in an environmentally responsible manner. As the operator of the first large-scale mining project to be developed in Kenya, Base Titanium’s Kwale Mineral Sands Project is also setting the benchmark for the future in occupational health and safety, environmental management and community relations.
