Min­ing

It’s one of South Africa’s most im­por­tant in­dus­tries and many peo­ple de­pend on it for em­ploy­ment

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FOR thou­sands of years peo­ple have been us­ing Earth’s rocks and min­er­als to make weapons, tools and or­na­ments.

These nat­u­ral re­sources are found in the planet’s crust and so are mostly ob­tained through min­ing.

Tin, cop­per and iron ore ex­tracted from the ground are used to make met­als such as bronze, iron and steel.

Gold and sil­ver have been val­ued for mil­len­nia for their rel­a­tive hard­ness and beauty.

Min­ing also ex­tracts the coal, oil and gas we use to heat our homes and run our cars’ en­gines.

FORMS OF MIN­ING

One of the most ba­sic forms of min­ing ac­tiv­i­ties is pan­ning. In cer­tain places pre­cious met­als such as gold are found washed up near rivers or in stream beds.

By rins­ing the sand with wa­ter in a bucket or us­ing a sift­ing de­vice you can check whether the sand con­tains gold or any other met­als. Gold is heav­ier than sand so will sink to the bot­tom when care­fully rinsed with wa­ter.

In ar­eas where min­eral de­posits are deeply em­bed­ded in the ground, deep-­level or un­der­ground min­ing is used.

A mine shaft is sunk ver­ti­cally into the ground at a seam or vein – a place rich in min­eral de­posits. Minework­ers are trans­ported

down the ver­ti­cal shaft by a lift deep un­der­ground. From the ver­ti­cal shaft they then dig

hor­i­zon­tal shafts to ex­tract the min­er­als from the seam.

Deep-level min­ing is dan­ger­ous. It gets hot in these shafts and breath­ing is dif­fi­cult. Some­times there are rock­falls or gas ex­plo­sions.

Open­cast min­ing is ba­si­cally large open pits with ter­raced sides. The top lay­ers of soil are re­moved and ex­plo­sives are used to break up the rocks. The ore is then trans­ported by large trucks to plants for pro­cess­ing. Coal and cop­per are mined this way.

Deep pits some­times con­tain ura­nium. Once all the min­er­als have been ex­tracted the pit is usu­ally filled in with rub­ble and soil.

Quar­ry­ing in­volves ex­tract­ing stone, typ­i­cally from a moun­tain side. In the past quarry work­ers used dy­na­mite, ham­mers and wedges to prise rocks from a moun­tain. To­day it’s done with mech­a­nised saws.

Oil plat­forms ex­tract oil and gas that are found in the se­abed deep be­neath the ocean. Some­times oil spills oc­cur dur­ing ex­plo­ration, pol­lut­ing the sea­wa­ter and de­stroy­ing ma­rine life in the process.

South Africa’s na­tional oil com­pany, PetroSA, ex­tracts gas near Mos­sel Bay and pro­cesses it into liq­uid fuel.

An­other min­ing tech­nique used to ex­tract gas or oil from the earth is frack­ing. This tech­nique in­volves in­ject­ing liq­uid un­der

high pres­sure into un­der­ground rock for­ma­tions to cre­ate cracks through which gas or crude oil can be di­rected via a pipe­line to wells on the sur­face.

Most forms of min­ing al­ter the sur­face of our planet in one way or an­other but cer­tain forms of min­ing do more dam­age than oth­ers.

LARGEST MINES IN SA

South Africa’s mines pro­duce many of the world’s com­modi­ties and have sev­eral of the largest re­serves of pre­cious min­er­als.

The coun­try has rich de­posits of gold, di­a­monds, plat­inum, ura­nium, chrome, vana­dium, palladium, coal, il­menite, iron ore, man­ganese, nickel, sil­ica, tin, zinc and zir­co­nium. At 4km deep, An­gl­o­Gold Ashanti’s

Mpo­neng gold mine, south­west of Jo­han­nes­burg, is the deep­est mine in the world.

The Big Hole, or Kim­ber­ley Mine, is the largest open­cast mine ever dug by hand. The mine is 1,6km in cir­cum­fer­ence and 214m deep.

Although it closed down in 1914 and no longer pro­duces di­a­monds the site re­mains a pop­u­lar tourist at­trac­tion.

The Pal­ab­ora mine near Pha­l­aborwa, Lim­popo, is 800m deep. The mine has been in op­er­a­tion since 1956 and to­day it’s the only mine in South Africa to pro­duce re­fined cop­per. Its an­nual out­put is about 60 000 tons of re­fined cop­per – enough to pro­vide for most of South Africa’s needs.

Mo­galak­wena is the largest plat­inum mine in South Africa. It was es­tab­lished in 1993 near Mokopane in Lim­popo and con­sists of five open pits, Sand­sloot, Zwart­fontein, Mo­galak­wena-South, Mo­galak­wena-Cen­tral and Mo­galak­wena-North, which range in depth from 45-245m.

Vene­tia di­a­mond mine opened in 1992 in the Vene­tia Lim­popo Na­ture Re­serve. This open­cast mine is the largest di­a­mond pro­ducer in South Africa and is al­ready 450m deep.

The Sishen mine near Kathu in the North­ern Cape is a 400-m deep iron ore mine. This open­cast mine has been in op­er­a­tion since 1953. Sishen has among the big­gest iron ore re­serves in the world. Since it started op­er­a­tions, more than 900 mil­lion tons of iron ore have been pro­duced.

Grootegeluk coal mine in Lim­popo has one of the world’s largest coal ben­e­fi­ci­a­tion plants and can process about 8 000 tons of coal an hour. Us­ing con­ven­tional trucks and dig­ging meth­ods the mine pro­duces about 18,8 mil­lion tons of coal a year.

The Cul­li­nan di­a­mond mine in Gaut­eng started op­er­a­tions in 1902 and is fa­mous for pro­duc­ing sev­eral of the world’s big­gest di­a­monds. Cul­li­nan has de­liv­ered more than 750 di­a­monds of more than 100 carats each. The mine is also the world’s only sig­nif­i­cant source of blue di­a­monds. It oc­cu­pies 39 hectares and is 190m deep.

GOLD Deep-level min­ers have very dan­ger­ous jobs. This is Mpo­neng mine, the deep­est in the world. SA has sev­eral of the world’s largest gold re­serves.

CRUDE OIL An off­shore oil­pro­duc­tion plat­form and sur­vey ves­sel in the North Sea.

DI­A­MONDS Vene­tia, an open­cast mine, is the coun­try’s largest pro­ducer of di­a­monds, de­liv­er­ing around 40% of South Africa’s an­nual di­a­mond pro­duc­tion.

IRON ORE ABOVE: Sishen iron-ore mine in the North­ern Cape is one of the largest open-cast mines in the world – about 14km long. RIGHT: Huge trac­tors that trans­port heavy weights are used on the mine. The big­gest one can carry al­most 500 tonnes.

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