General
Low tech mining delivers top

Mining is once again making South Africa’s economy boom, and in particular the economy of the small village of Swartruggens in the North West Province. Jenny Baker reports.
The village of Swartruggens lies on the world-class Bakwena Highway that connects the Botswana border post Skilpadhek with the South African metropolis of Pretoria. Swartruggens residents and visitors use state-of-the-art technology
to smooth their daily lives – and yet some things have not changed in almost
a century.
Previously regarded as a one-horse town in the middle of nowhere, Swartruggens is growing chiefly due to new mining money reaching it from other North West mining towns via the smooth, broad, new highway.
However, Swartruggens has mines and quarries too, some in work for generations. One such quarry is Mullett Slate on the Mullett family farm Wagenboomskop, which has been in profitable operation since the 1930s, and with pretty much the same machinery operated by pretty much the same families as 70 years ago. Says family spokesperson Eddie Mullett: “It’s not that we’re resisting technological progress…it’s just that what we have works for us.
“It’s a very labour intensive quarry and the people who work here, me included, know the land, we know the stone. Much of our success depends on knowing what we’re looking at, classing the seam visually, judging how to get the best out of it, and then using our eyes and hands to do it. And manual labour means jobs for locals – also important to my family.”
Eddie explains that in previous years the size of the pit and rehabilitation arrangements were left mostly to the judgment of the mine manager. These days the Coleman family, who rents the quarry from the Mulletts, is bound by the provisions of the R52,000 (NZ$10,500) mining permit that lapses this year and must in future be renewed on an annual basis at a cost of $4500 per year.
He says the money, deposited as a rehabilitation fund guarantee, allows Mullett Slate to mine two pits of no more than 1.5 hectares each. The pit hired by the Colemans opened in December 2000 and will eventually leave an approximately 30 metre deep, 50 metre long crater with a 100 metre face wall, which will then be rehabilitated by backfill and landscaping. Earlier pits are already rehabilitated or in the process of returning to a native vegetation state.

A simple process
A pit is started by digging an entrance area to a depth of around 20 to 30 metres, subsequent to which mining becomes uneconomical. For opening a pit, and to remove the two metre overburden, the operators periodically hire excavators.
A contractor with a ‘blasting ticket’ visits on a regular basis to open up the face for production. Once this is done, the 35 stockmen start removing the slate layers in terraces from the top layer to the footwall.
A stock miner uses a crowbar to lift the slabs and a hammer and wedge to split them into the maximum acceptable width of 25mm. Slabs sent to the plant must also be neither larger than 600mm by 600mm nor smaller than 200mm by 200mm…again, workers mostly judge this visually. Two workers load the slabs onto a trailer, pulled by an ancient tractor to the milling plant.
At the milling plant, foreman Ishmael Kgajane oversees the ‘weighing’ process. The tractor loaders lay the slabs out flat, side by side, on a 25 square metre area, shown by experience to even out to one tonne per ‘weighing’. The stockmen, all subcontractors, are paid by tonnage. Ishmael and his colleagues are happy with this state of affairs: “The more we work, the more we get paid,” Ishmael says.
And they don’t sit on their hands – pulling in enough slate over and above the 15 square metre per person per day required for the operators to justify the mine’s continued existence by
showing a profit.
At the milling plant, the 13 millers, who are on wages, take over. Two millers each operate a ripper and one miller operates a cross cutter. The basic ripper and cross cutter designs have been in use since the 1930s, later modified by Eddie’s grandfather, Fred Mullett, and in turn by his son Neville, Eddie’s late father.
“Dedda and I still built one of these rippers together,” Eddie remembers. “These machines are safe for our workers, they are efficient, easy to maintain, and they last just about forever.”
The two rippers each operate with four diamond-tipped blades covered by steel blankets. Powered by generators, a gearbox drives the two metres per minute conveyor on which the slabs travel. The blades cut the slabs in two 300mm and one 400mm strips, the most popular sizes, but can be adjusted for special orders.
The cross cutter operator now places the strips transversely on the moving cross cutting table, which he then feeds into the blade housing unit to get the basic end product – square tiles.
The rippers and cross cutters require continuous water lubrication. Water is a scarce commodity at the best of times. This year, Swartruggens had a dry spring and summer, its traditional
rainfall period.
In wet years, the water for the production process comes from the Elands River that runs adjacent to the quarry. At present, water is trucked in and stored in a dam. Management has traditionally always recycled and purified water. These are practices widely in use in South Africa over the past century, and considered acceptable to produce drinking water.
Again, recycling and purification are done the simple way – catching runoff in a settlement pond, and then draining the settlement pond into the main dam, before the water is fed onto the sensitive blades again.
Once cut, quality controllers square and size the tiles by hand. The tiles are separated into 200mm by 200mm units of between 9mm and 13 mm thick, 300mm by 300mm units of between 13mm and 15mm thick and 400mm by 400mm units of 15mm to 17mm thick. Other quality controllers tidy up the tiles with a hammer and chisel, leaving one face rough and the other silky smooth.
Packers now fill the crates, and the loader driver loads the crates onto the buyer’s truck under the watchful eye of Jannie Coleman. The tiles are for domestic use, but during the 70s and 80s, when the Mulletts were in partnership with Keeley Slate, the latter also exported to Europe.
Quality product
Mining the slate is a time consuming process, but one that leaves a relatively small footprint, and a quality end product that is worth the trouble. Eddie says only about 30 percent of the slate taken out makes it to the truck. The rest is waste – not strong, durable or beautiful enough.
Having grown up in the sturdy Mullett farm home with its traditional thatched roof and slate floors, finishes and decoration throughout, his enthusiasm for the product has only grown over the years.
“It’s a little part of Africa right in your home. It simply is beautiful and functional to me in a way other same-purpose products can never be,” he says.
The Mullett women – mother Lenie and daughters Charmaine and Lynette – are pursuing their own careers. Eddie has other plans, too, so the quarry is now for sale. It’s the end of a mining dynasty spanning three generations.

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