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Base Metals and Minerals

Andalusite

South Africa, with more than 50 million tons of alumino-silicates, contains around 40 per cent Andalusite of the world’s known reserves of these minerals and accounts for nearly half of the western world’s production. A natural silicate of aluminium, andalusite is the material used in refractory bricks which line blast furnaces. In South Africa andalusite is mined in Mpumalanga near Lydenburg and in Namaqualand south of the Orange River.
Apart from a tiny deposit in France, South Africa has the only anadlusite reserves in the world.
Like platinum, manganese, chrome. vanadium and cobalt, among others, andalusite is regarded by the United States as a ’strategic’ mineral. Furthermore, as French andalusite has a different particle size, there is no material available which can be substituted for South African (coarse grade) andalusite; as a result, the US is reliant on South Africa for its entire imports of andalusite.

Antimony

Antimony plays a small but significant role in South Africa’s base metals output. Most of Antimonythe concentrate is beneficiated into antimony trioxide, a vital ingredient in flame-retardant industrial products while the main (though declining) use of antimony metal is in the storage-battery industry. Antimony is also essential in producing solder, bearings, space-probe components, lubricants, vulcanising agents, medical preparations and tracer bullets. Although South Africa accounts for only about 12 per cent of global output, it is believed to be the main source of antimony oxide imports into the United States.

Asbestos

South Africa possesses only about 10 per cent of the west’s asbestos fibre reserves and produ Asbestosces around nine per cent of its output.
The use of asbestos is now mainly restricted to the ’safe’ core businesses of building materials and piping in water-reticulation systems. In spite of its restricted use the international market remains healthy.

Chromium

About 58 per cent of the west’s chromium ores and 68,3 per cent of the world’s known rese Chromiumrves of chromite, the principal chromium mineral of economic importance, are located in South Africa’s Bushveld Igneous Complex.
More than 85 per cent of all chromium produced is destined for the production of stainless steels and the closely related heat-resistant steels. Chromium, together with other metals such as copper, nickel, titanium and vanadium, is added to iron to produce steels with greatly increased strength and rust- and corrosion-resistance. Ferrochrome is an essential ingredient of stainless steel.
The chemical industry absorbs about 25 per cent of chromium production, Chromium chemicals have a great variety of uses. Widely used as pigments, they also feature as tanning salts, oxidising agents and catalysts. Other applications include the chromium plating of metal surfaces, photography and pyrotechnics.
Another main use for chromium and its compounds is in refractories, which account for 14 per cent of production. Because of their high melting point, stability and chemical neutrality, chromite sands and refractory bricks containing chromite are used for casting moulds and furnace linings.

Cobalt

In South Africa, cobalt is found as a minor element in the base-metal sulphides of the Merensky Cobalt Reef of the Bushveld Igneous Complex (BIC) from which platinum group metals are extracted; it is also found in a number of chromite layers of the BIC.

Copper

South Africa’s copper occurrences stretch from Phalaborwa and Messina, through the Bushveld Copper Igneous Complex (BIC) and the northern and north-western Cape to Namaqualand. Six of the occurrences support major mining operations, where copper in the BIC is being recovered as a by-product of the platinum industry.
South Africa’s production of cathode, blister and concentrates amounted to about 150 kt in 2000, of which about half was exported.
Although slowly being superseded by fibre optics in its main application - the generation and transmission of electricity and information - copper still has widespread use in the manufacture of electrical wire and cable, in the automotive and construction industries, as well as in alloys and tubing for a host of applications.

Fluorspar

South Africa’s fluorspar (natural calcium fluoride) reserves exceed 30 million tons. It has the Fluorspar third largest reserves in the world and accounts for around 30 per cent of the western world’s and about 10 per cent of all known reserves.
Fluorspar is used mainly in the aluminium, steel and chemicals industries. Although no immediate significant impact is anticipated regarding demand for acidspar, the decision by western leaders to tighten the requirements on chlorofluoro-carbon emissions, with the aim of eliminating such emissions entirely, is bound to have a substantial effect eventually an the acidspar market.

Granite

Granite and norite (black granite) account for 98 per cent of dimension stone production in S Graniteouth Africa. The local granite quarrying industry is dominated by two companies - Kelgran (Pty) Ltd and Marlin Corporation Ltd. Between them they control 31 of the 40 operational granite quarries in the country, and are responsible for 72 per cent of the total granite production (rough blocks).
Ninety per cent of all rough blocks sold are exported without further beneficiation.
The red granites and black/grey norites of the Bushveld Igneous Complex form the backbone of the South African dimension stone industry.

Iron ore

South Africa’s total reserves of iron ore amount to 9 300 Mt, or nine per cent, the sixth largest i Iron oren the world.
The principal deposits are located in the Northern Cape at Sishen, from where export ore is transported via a purpose built rail link to Saldanha Bay on the Atlantic Ocean 800 kilometres away. Other high grade haematite deposits occur near Sishen at Thabazimbi on the northern rim of the Bushveld Igneous Complex (BIC) and elsewhere on the BIC.
Iron is largely used in the form of alloys with other metals in the production of a variety of steels from cast iron to stainless steels. Added value in the context of iron arises from a higher production of ferro-alloys and speciality steels, made by the alloying of iron with other metals found in abundance locally. As well as exporting mined ore, Iscor is making steel to compete on world markets.
Developed world ore markets are steadily growing, with the Japanese demand recovering, while the Asian markets, led by China and Korea, are advancing strongly.

Lead

South Africa possesses around three million tons of lead deposits. Lead
In South Africa, surface exploration drilling conducted during 1999 at Anglo Base Metal’s Black Mountain Mine in the Northern Cape established a hitherto undiscovered down-dip extension at a depth of between 900 and 1 700 m below surface. A feasibility study completed in May 2000 prompted Anglo to announce plans to invest $110 million to open up this newly discovered extension.
Lead is one of the most widely used metals in the industrial world. By far the biggest use for lead is in car batteries, which consume at least half of the world’s annual production. The continuing expansion of the motor industry with the consequent demand for replacement batteries has underpinned the steady growth in demand for lead, though its use in fuel additives is declining as consumption of ’unleaded’ petrol continues to increase in the United States and the European Community.

Manganese

With reserves totalling in excess of 4 000 Mt, 80 per cent of the world’s known manganese ore de Manganeseposits are located in the Northern Cape and the North West province.
High grade metallurgical manganese ore is generally smelted and refined to produce ferromanganese, an alloy which has long been used in the processing of steel. With much of the manganese alloy production in other countries originating from South African ore. Manganese is classified as a ’strategic’ metal by the United States: that country relies on South Africafor around 30 per cent of its total manganese content in all forms. including 25 per cent of its ferromanganese intake.
Just as the main downstream use of ferrochrome is stainless steel. ferromanganese .s beneficiated as carbon steel. As an alloying agent, ferromanganese is invaluable in imparting strength, toughness and abrasion-resistance to steel, with the world crude steel market consuming more than 90 per cent of manganese output. The metal is also used as an alloying agent to strengthen aluminium and is added to copper to form a wide range of manganese bronzes.
Manganese dioxide is a powerful oxidising agent with a variety of chemical applications, including use in dry cell batteries and in acid leaching to recover uranium and zinc from their ores.
Considerable value added potential exists in the production of manganese chemicals. These are used principally in making fungicides for agricultural use - a sector hardly touched on by South Africa, which supplies only some three per cent of the world’s manganese chemicals requirements.
Against a background of rationalised manganese production world-wide, a shortage of high grade manganese ore in international markets and still high demand for carbon steels which has seen price gains for both manganese ores and alloys.

Nickel

More than 12 Mt of nickel, representing 8,5 per cent of the world’s nickel reserves, are locate Nickeld in South Africa’s Bushveld Igneous Complex where the nickel bearing horizons occur over a total length of about 250 kilometres.
Nickel is vital to the steel industry and especially the stainless steel industry, which is the metal’s biggest market. It has played a key role, too, in the development of the chemical, aerospace and armaments industries. The metal’s greatest value lies in the alloys it can form with other elements, where it adds strength and corrosion resistance over a wide range of temperatures.

Silver

Silver is an important constituent of gold and platinum ores in South Africa and occurs too in th Silvere ores of the base metals (zinc, lead, and copper).
Silver is used for coinage, photographic materials, brazing materials, and as a catalyst. Pure silver, like gold, can be rolled into foil, drawn into fine wire, and beaten to leaf. However, as silver is too soft in its refined state to stand up under constant wear, it is usually alloyed with copper before it is made into any consumable such as coins, jewellery and tableware.
Silver compounds are used to coat films and in silver plating. The metal’s high electrical and thermal conductivity and superior oxidation resistance have led to its widespread use in electrical and electronic applications. Other applications of the metal include the manufacture of silver paints, while silver batteries find special uses in aircraft and various types of military equipment.
As the ’90s opened, the silver surplus was on the increase again, while the price of the metal remained at a critical low point. The strength of the dollar, the lack of speculative buying by investors, destocking by fabricators and, most important, the striking increase in silver output, have greatly increased supply. However, rising industrial usage, in particular, could bolster support levels for the metal.

Titanium

South Africa’s reserves of titanium contained in ilmenite, as well as rutile and leucoxene, are Titaniumconcentrated mainly in extensive titanium-bearing deposits in black sands in the Richard’s Bay and St Lucia areas of northern KwaZulu Natal. The Richard’s Bay titanium reserves are the fourth largest in the world.
During the last two decades or so the importance of titanlure - one of the toughest, lightest and most corrosion resistant materials known to man - has steadily increased throughout the world. Titanlure has become one of the most highly rated of all metals. Titanlure alloys are used in the manufacture of aerospace components, guided missiles, military hardware, camera bodies, tube condensers and turbine blades with increased usage in the nuclear industry, chemical plants medicine and marine parts.
Ilmenite and rutile are rich in titanium dioxide, which is most commonly used to add opacity to paints, paper, plastics, fibres, floor coverings and enamels - to name but a few - while the pigment industry is the world’s largest user of titanlure dioxide.

Uranium

African production of uranium oxide, currently accounting for more than 20 per cent of wo Uraniumld output. South African output is mainly produced as a by-product of gold and copper mining.
In recent times, holders of uranium inventories have released this material on the spot market, which has kept the market under pressure, and has led to softening prices
Many experts believe that in the future nations will have little alternative but to use more nuclear power - in part owing to the need to reduce the usage of fossil fuels in order to curb the ’greenhouse’ effect.

Vanadium

South Africa’s Bushveld Igneous Complex contains more than 5 million tons of vanadium ore Vanadiumreserves, which represents about half of Western world reserves and one-third of the global total.
South Africa is the major player in the vanadium market and, because of the accessibility of high-grade vanadium-bearing deposits and the expansion of capacity, it is likely to remain so.

Vermiculite

With vermiculite ore reserves at nearly 80 million tons, South Africa has the second largest re Vermiculiteserves of the metal: representing about 40 per cent of the world total..
Vermiculite, a partially decomposed mica with the unique characteristic of expanding some 30 times in volume when heated, is widely used in fire proofing and acoustical plasters, for heat insulation, as a growing medium in horticulture, agriculture and hydrophonics and in other applications where its light weight and other industrial properties can be utilised.

Zinc

South Africa, with around 15 million tons of zinc reserves, contains about 3,5 per cent of globa Zincl deposits of the metal. Large, economically viable deposits of mixed sulphides are found in three areas of the Northern Cape in the Black Mountain/Gamsberg area, around Prieska, and near Pering in the north of the province. Black Mountain/Gamsberg is the biggest and highest grade zinc deposit in southern Africa.
Zinc’s main application is in the protection of iron and other metals from corrosion, it is also used in three main semi fabricating areas: galvanising, the manufacture of zinc based casting alloys and in brass. Current high zinc prices are partly the result of a consumer switch towards quality - for instance, the increased use in car bodies of galvanised steel which has greater resistance to rust than ordinary mild steel. In South Africa. there is growing demand for galvanised steel from the mining industry - over the next few years about 60 000 tons of galvanised steel will be used in mine shafts alone.
Zinc chromate is used extensively as an undercoating; while zinc oxide is utilised in rubber production, paints, ceramics, floor coverings and pharmaceuticals.

Zirconium

Zirconium is spread widely through the earth’s crust, being present in several mineral forms, Zirconium although only two are of current commercial significance: namely, zircon sand containing zirconium as the silicate, and baddeleyite as a form of zirconium oxide.
South Africa contains 14,3 Mt, 22,1 per cent of the world’s known reserves and accounts for 24 per cent of output.
Both zircon and baddeleyite are utilised in the form of sand or micronised powders, the major applications being in foundries and refractories. Other uses include abrasives, ceramics, alloys, chemicals and leather tanning. Zirconium metal is renowned for its excellent corrosion resistance and is employed as a component for alloys in chemical processing plants and in aerospace engineering. It is also used for fuel cladding in nuclear reactors. Finally, high technology zirconium ceramics are being tested for hot section service in the future generation of uncooled internal-combustion engines.