Steyn Diamante, arguably the most successful alluvial diamond miner operating in the Northern Cape, has bolstered its mining fleet over the past year with several ‘new generation’ high-end machines from Volvo Construction Equipment (Volvo CE), including an L350H wheel loader, the flagship of Volvo’s loader line-up, and three Volvo A60H articulated haulers, all supplied by Volvo CE dealer Babcock. Modern Mining’s Arthur Tassell recently visited Steyn Diamante’s Schutsekama mine to talk to Schalk Steyn, the company’s founder and CEO, and view the new machines in action.
The Schutsekama mine is located south-west of Kimberley on the Riet River, a tributary of the Vaal, downstream of the village of Ritchie. It is currently Steyn Diamante’s only active operation although the company has in the past mined at several sites along the Middle Orange River (MOR), which – along with the Vaal – is the main source of the Northern Cape’s alluvial diamonds. Steyn Diamante established Schutsekama in 2015 and the remaining mine life is currently estimated at seven to eight years.
Steyn Diamante’s Volvo L350H loads one of the company’s three Volvo A60H articulated haulers.
Explaining the mining operation at Schutsekama, Schalk Steyn says it is essentially a large-scale earthmoving exercise. “The diamond-bearing gravels, which are buried under up to 15 m of overburden, have a grade which only averages around 0,4 carats per hundred cubic metres of gravel, which is quite low even by the standards of alluvial diamond mining,” he says. “So to survive we have to move vast amounts of material as efficiently and economically as possible. Typically, we’ll handle between 700 000 and 850 000 tons of material a month.”
Currently, there are two active pits at Schutsekama. Diamond-bearing gravel from the pits is mined by heavy excavators and then trucked just a few hundred metres to four Finlay 893 screens. The oversize material is scalped off and taken back to the pits where it is used for rehabilitation while the minus 100 mm fraction is then sent to the processing plant, which consists of a scrubbing section followed by eight Russian-made Bourevestnik X-ray sorters divided into three lines – oversize, medium and fines. The final concentrate is hand sorted.
Says Steyn: “Traditionally, pan or DMS plants are used to process diamond-bearing gravels but we’ve been using the Bourevestnik technology since 2010. We find the machines are very effective and we’re very satisfied with the performance they deliver.”
Steyn says that what makes Schutsekama profitable is the value of the diamonds recovered – which is generally in the range of US$1 500 to US$2 000 per carat – and the occasional recovery of very large stones. “The biggest we’ve had so far is a ‘fancy yellow’ of nearly 160 carats,” he states.
Commenting on what makes for success in the hard, unrelenting game of alluvial diamond mining, Steyn says that management has to be hands on. “There’s no margin for error when you’re dealing with a low-grade deposit such as this. For example, it’s important not to handle material more than once. If you let things slip, you can be out of business within weeks. So we place a great deal of emphasis on having capable, pro-active management. The mine manager here at Schutsekama is Wikus de Winnaar, who is extremely experienced, and I myself am on the mine on most days. We also place great store in having a well-trained, well-remunerated workforce as well as a fleet of modern very well-maintained machines.”
Although he is now a near legendary figure in alluvial diamond mining circles, Steyn started his career in the platinum mines in the Rustenburg area, having joined JCI as a learner official in 1978. He quickly became a shift boss and then a mine captain and also worked as an underground manager from time to time on a relief basis. In 1984 he decided he wanted to work for himself and subsequently set up his own blasting business. His first contact with the diamond mining industry was in the mid-90s when he mined – not very successfully, he concedes – a diamond deposit in the Central African Republic. After a second stint in the Central African Republic in the late 90s, he started to look at alluvial opportunities in the Northern Cape, which eventually led to him establishing Steyn Diamante in 2004.
“Since the company was founded, we’ve experienced the good times and the bad times but generally we’ve been successful,” Steyn recounts. “The biggest challenge we ever faced was in 2008 and 2009, when the global financial crisis led to the price of rough diamonds falling very sharply. We managed to survive by retrenching and cutting our costs drastically but many of the Northern Cape alluvial diamond miners disappeared as a result of this downturn. Today there are far fewer participants in the industry – in fact, only a handful of any significance.”
He adds that Steyn Diamante is fully empowered at the holding company level, with a BEE partner having a 50 % stake in the company. “Our partner is not just a passive investor but a very active participant on a daily basis in the operational side of the business,” he says.
Steyn Diamante runs a mixed fleet of mining equipment at Schutsekama, with the biggest machine being a 230-ton class Liebherr excavator equipped with a 13,8 m3 bucket which works in conjunction with 100-ton capacity Cat rigid trucks. Volvo machines are well represented in the fleet – apart from the L350H and the three A60Hs, Steyn Diamante also operates three Volvo A35 articulated haulers and four EC480 excavators.
According to Steyn, the fleet deployed at Schutsekama differs from those mobilised at previous Steyn Diamante operations. “Because of the high volumes, we’ve gone for heavier machines,” he explains. “In the past, we would typically have had around 100 machines and about 300 operators. Here at Schutsekama we have 45 machines and around 90 operators.”
Steyn is a great believer in the Volvo brand and has, over the years, purchased over 100 Volvo machines, all of them acquired through Babcock’s Kimberley depot, which has been run since start-up by Johan Vorster. “Our experience is that the Volvo machines are top-notch,” says Steyn. “Their performance and reliability is excellent and their fuel efficiency ranks with the best we’ve seen. We also expect good aftermarket support from all our suppliers and Babcock has not let us down in this respect. We have a full-time Babcock mechanic on site and we also get first-rate backup from the Kimberley depot.”
The 50-ton class Volvo L350H operating at the mine – delivered three months ago – is the first to be deployed in South Africa. Powered by a D16E engine offering a maximum power output of 397 kW and fitted with a 6,8 m3 capacity bucket, it is Volvo’s largest wheel loader to date and is equipped with the latest technology dedicated to reducing fuel consumption and engine emissions.
The three Volvo A60H articulated haulers have been on site for just over a year and are the first to have been ordered in South Africa after their local launch at Babcock’s Middelburg branch in May last year. The A60H is notable for being the world’s largest true articulated hauler and has sold well locally, with nearly 30 now in operation at sites in both South Africa and Namibia.
Steyn says he is impressed by both the L350H and the A60Hs. “We haven’t had the L350H for too long but our experience thus far is very positive and we particularly like the high lift it has. We’ve had the A60Hs for much longer and they’re really earning their keep. The prime reason we bought them is that it is difficult for our rigid trucks to operate in the pits in the rainy season. In fact, when conditions are really poor, the A60Hs are the only trucks that can go into the pits and get out the material efficiently.”
Steyn Diamante’s investment in new Volvo machines is continuing and, on the very day that Modern Mining was on site, Steyn committed to purchasing three of Volvo’s all-new R100E rigid haulers, which were launched globally in April this year at the Volvo CE factory in Scotland. The R100E and its smaller siblings – the 45-ton R45D, the 60-ton R60D and the 72-ton R70D – are the first rigid trucks to be manufactured and marketed under the Volvo name and the three units to be delivered to Steyn Diamante represent the first South African order for machines in the new range.
The R100E is a 100-ton capacity hauler, which is a very competitive segment of the rigid hauler market. “It will be very interesting to see how the R100Es shape up against the very capable 100-ton rigid trucks we already have on site,” says Steyn. “We’re looking forward to receiving them and believe that they will prove themselves just as effective as the other Volvo machines in our fleet.”
Photos by Arthur Tassell