Triumphrat

DaveB

Although I’ve worked in industry here for nearly 30 years, I’ve had little connection with our gold mining industry. I thought it would be interesting to find out something about it and write about it. However, I don’t pretend for one minute that this is comprehensive or complete.

Gold is the chemical element with the symbol Au (Latin: aurum) and an atomic number of 79. Apart from its well-known use as a precious metal used for jewellery and coins it is super ductile, malleable & conductive, yet highly resistant to all common forms of corrosion.

Records of human use of the metal go back beyond 2,500 BC. There are many people & organisations on the web that attempt to estimate the total amount of gold ever mined. The common consensus is that the total is approximately 160,000 tonnes to date. This could be represented by a cube of purified gold with an edge length of just 20.5 metres. By 2008, South Africa was no longer the biggest producer of gold, having been overtaken by both the USA & China (with Australia now a very close fourth) in the past couple of years. However, it is estimated that South Africa has mined nearly half of the world’s total gold production over the years.

]The city of Johannesburg (aka ‘Joburg’, ‘Jozi’) was founded as a result of the Witwatersrand Gold Rush in 1886, which resulted in the discovery of some of the largest gold deposits the world has ever seen. One of the native names for the city, Egoli, means ‘place of gold’. The gold fields located within the basin of the Free State and Gauteng (formerly Southern Transvaal) provinces are extensive in strike and dip requiring some of the world's deepest mines. The Second Anglo-Boer War of 1899–1901 was at least partly caused over the rights of miners and possession of the gold wealth in South Africa.

If you travel in any one of three directions (west, south or east) out of Johannesburg you will soon see gold mines. I mean dozens of mines. I remember reading in the Nineties that there are approximately 17,000 controlled underground detonations in this country each and every day, the great majority in the gold mines. Gold mining is ugly- the mines themselves are ugly, the working conditions are unpleasant and extremely dangerous and the processed ore stacks, or dumps, are unsightly.

I travelled west to the town of Carletonville and went past the entrance to AngloGold Ashanti’s Mponeng and TauTona mines that stand virtually side-by-side. Each employs just under 6,000 personnel and they are the deepest mines, both now at a depth of about 3,800 metres. There are plans to go down to 4,500 metres. I’ll concentrate on the latter because it was easier to photograph and because it has been featured in National Geographic’s ‘MegaStructures’ TV series:


Pic from the AngloGold Ashanti website:


All around there are many other mines and process plants:

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The World looks better when viewed through a dark tint Arai visor

DaveB

I travelled a few km north to Randfontein and the scene was similar:


Except that this time I could just make out the tower blocks of downtown Johannesburg, some 25km away:

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The World looks better when viewed through a dark tint Arai visor

DaveB

It is possible to book a visit to a working mine, but there is an easier way. The Gold Reef City theme park is situated just 5 km south of Joburg City Centre and it is built on the site of a former mining complex called Crown Mines, which in its 70 year history extracted 1,400 T of gold. Thus the mine, whilst now a museum piece, is authentic:



Our group of visitors descended a mere 220 metres in the cage down #14 shaft. It was actually the 13th shaft sunk but was called no. 14 for superstitious reasons!



The first thing we saw was a Swiss Sulzer pump driven by a British Thomson-Houston induction motor:



Then we saw this fabulous mercury arc rectifier, probably over 70 years old and still working:

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The World looks better when viewed through a dark tint Arai visor

DaveB

The cabinet holding sticks of dynamite. The top is deliberately sloped & canted so that the miner couldn’t rest his naked flame lamp on top!:



Safety notices from a bygone age in Fanagalo (pron. funna-guh-law) which is the universal mine language used here. It has a vocabulary of about 1,500 words (from Zulu, Afrikaans & English) and has very little grammar.



A skip used to remove ore from the workface:



A miner demonstrating the compressed air operated, water fed (to keep the dust levels down), pneumatic jackhammer drill. Dynamite would then be inserted in to the drilled hole to blast the rock. The work area is known as the ‘stope’ and the pit props are made of eucalyptus. There are also steel tie rods in the roofs of the tunnels and stopes. The jackhammer is incredibly loud and sounds much the same as a heavy calibre machine gun:

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The World looks better when viewed through a dark tint Arai visor

DaveB

After the underground tour it was on to the smelting room. The gold is heated to over 1,000 deg C:






The finished (sorry, out of focus) ingot, weighing about 12kg (25lb):

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The World looks better when viewed through a dark tint Arai visor

DaveB

The gold price & the effective value of the ingot on the day I visited:


After I left Gold Reef City I travelled a mere 5 or 6km SW to check up on progress on the stadium that is scheduled to host the final of the FIFA Football (Soccer) World Cup in July 2010. Its design is based on the shape of the calabash. It may appear that this is off topic but it’s not; there’s a direct connection to the World Cup later in this write-up.

Looking good:


There’s even a mine dump in the background on the right hand side.

The mined ore is crushed fine. Then a sodium cyanide solution is used to dissolve the gold in the ore. The processed ore is then stacked in dumps that are numerous in many areas of the country. The dumps are even included in digital mapping for aviation and radio path profiling purposes. The ore is virtually inert after the chemical leaching process so topsoil and other treatments are needed to get anything to grow on these man made hills. They sure are ugly!

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The World looks better when viewed through a dark tint Arai visor

DaveB

Ten years ago, in 1999, the British Government decided to sell part of the country’s gold reserves http://www.independent.co.uk/news/business/britain-stuns-markets-with-plan-to-sell-gold-reserves-1092218.html. It was followed up by more sales into 2002. The total was 395 tonnes, nearly 60% of the reserves, sold at an average price of $ 280 per oz., not far off the lowest price at any time during the preceding 20 years. This deed didn’t just affect the markets; it also staggered the executives of the Bank of England.

This is how this action was reviewed by one particular journalist, ten years on, earlier this year http://news.sky.com/skynews/Home/Business/Gordon-Brown-Sells-Gold-Reserve-Ten-Years-On-Gold-Underlines-Its-Worth-Daniel-Wills-ETF-Securities/Article/200905215277708

Hindsight is a perfect science. Gold, as I write this in early Nov 2009, is currently trading at over $ 1,000 per oz.

The architect of this sale was the then Chancellor of the Exchequer, Gordon Brown, who is currently the UK’s embattled Prime Minister. Back in 1999 I was working in the East Rand town of Boksburg (I’d also previously lived there so I know the place well). It’s about 25km east of Joburg. The town virtually grew up around and exists because of ERPM (East Rand Proprietary Mines). Back in ’99 the then owners of the mine wanted to sell it, I suspect because it was old, therefore relatively inefficient and therefore unprofitable. They also knew that they could not just close it because a whole town and community would suffer terribly. Thus the UK bullion sale was very big news here. Eventually ERPM was sold and it’s working today and surprise, surprise, it’s currently profitable. ERPM.

How, as an Englishman, can I write about this story dispassionately? Well, I’ve known about it for 10 years, so there’s no shock value to me. However, I wouldn’t mind betting that the owners, shareholders, management & staff of ERPM, both past & present, will enjoy a hearty chuckle when Gordon Brown finally plummets from power. I’d further wager that ERPM will still be functioning long after he isn’t.

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The World looks better when viewed through a dark tint Arai visor

DaveB

It was then on to the Mint, some 40 km north of Johannesburg:




Unfortunately cameras are not allowed in the museum & shop complex.

The history of coins in this country is depicted, as are the mould making and stamping processes.

One of the best known of the Mint’s products is the Krugerrand. The minted quality of these coins is superb. It seems as though the Krugerrand is regaining its popularity with investors in these current difficult economic times:


The Mint has also produced a limited edition, FIFA endorsed gold 2010 World Cup coin set to commemorate next year’s event:

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The World looks better when viewed through a dark tint Arai visor

DaveB

So, I guess it’s worth asking the question; why do we have such large gold deposits and other mineral wealth in our neck of the woods? Well, more and more scientists are linking it to this single massive event which occurred in prehistoric times.

OK, we’re talking big here. Very, big indeed.

A 1,000 megaton impact crater!

When such a crater is caused by a ‘bolide’, a large meteorite, asteroid or comet head from space colliding with Earth it is described as an ‘impact event’. The term ‘astrobleme’, which translated from the Greek literally means ‘star wound’, is used by geologists to describe the affected area on Earth.

The story goes that over two billion years ago a meteorite some 10 kilometres wide, larger than Table Mountain:


crashed in to Earth at a speed of around 16,000 metres per second, impacting 100 kilometres SW of where the city of Johannesburg now stands, with an explosive force equivalent to 1,000 megatons. That is over 60,000 times more powerful than the A-bomb dropped on Hiroshima. It is thought that 70 cubic kilometres of mother Earth were instantly vaporised- an event that some scientists believe released so much oxygen in to the Earth’s atmosphere that it resulted in fundamental global climatic and atmospheric changes of such a scale that may have been a major catalyst in the formation of multi-cellular life forms on Earth. The Earth’s crust was melted to great depth, possibly more than 10 km down, and this molten mass of rock and minerals then rose upwards to form the central rebound crater. Oh yes, it was the big one!

The impact was centred just south of the Vaal river in the neighbouring Free State province where the dorp (town) of Vredefort is today. The original crater was + 300 km in diameter but the outer rim has since eroded away. What is left to be seen is only part of the central rock rebound, most of which has also eroded, which itself is 70 km in diameter, and is named The Vredefort Dome. In 2005 it became a UNESCO World Heritage Site.


All that’s to be seen today are shallow conical hills:


Try as I might, I cannot find a term to describe people who take an interest in astroblemes- astrobleme fanciers if you will. So I made up my own word and I call us ‘Blemers’. So I hitched up with my good friend & fellow blemer RickSuzuki and off we went. We first went in to the town of Parys (pron. pa-race) & then headed north across the Vaal River to the town of Potchefstroom. I’d only travelled this road once before, some 25 years ago. I remember at the time wondering why there were scenic hills here in an otherwise flat and featureless landscape. All these years later I now realise that these hills are the edge of the rebound crater.

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The World looks better when viewed through a dark tint Arai visor

DaveB

After meandering around the northern edges of the crater we made it in to Vredefort. Some of the geological accounts of this area make mention that we’re standing on what was once ocean bedrock; rock movements caused by entirely different geological events (plate movements). It was a very strange feeling because, a) we’re 640 km/400 mi from the coast and, b) we’re a mile above sea level.

If you consider that, in addition to the Vredefort astrobleme and the plate movements, there is another ‘top ten’ astrobleme named the Morokweng crater to the west, the small Ttswaing astrobleme to the north and then the Pilanesberg volcano (which is reckoned to have had a 7,000 metre high cone before it blew its top) also to the north and it becomes obvious that many enormous geological events have occurred in this area over hundreds of millennia. The region concerned is plentiful in gold, diamonds, platinum and chromium. There may be other minerals as well. It surely cannot be coincidence that Vredefort is just about in the dead centre of the highveld gold reef…..

Anyway, I feel confident enough to postulate the following.

DaveB’s Big Bang theory:
Our mineral wealth in South Africa is due to gargantuan near-catastrophic cosmic bolide bashings!

That is my theory, it is mine, and belongs to me and I own it, and what it is too (Ó Miss A. Elk ).

Should anyone wish to find out if you have an impact structure in your hood, all verified astroblemes are listed in the Impact Structure Database. If you haven’t got one near you, well I’m afraid that’s just how the cosmic collision cookie crumbles.

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The World looks better when viewed through a dark tint Arai visor