Modern Mining January 2015

DIAMONDS

and it also owns the Mothae kimberlite pro­ ject in Lesotho, which is just 6,5 km from the Letšeng mine. Lucara was considering expanding the current bulk sampling plant on site to treat Mothae’s significant resource of weathered ore – as the first stage in developing a fully fledged mining operation – but has recently announced that it intends divesting itself of Mothae. In a statement issued early this year (2015), Lucara said that while it had evaluated multiple devel- opment options for Mothae, it had concluded that the project did not meet “the company’s disciplined investment criteria for its targeted return on capital”. Summing up, Day says that with Karowe in full production, Lucara is becoming a significant player in the diamond market. “We’re a young company but we’ve achieved a great deal over our relatively short history,” he says. “Karowe is our flagship and will underpin Lucara for years to come but we will not necessarily remain a ‘one-mine company’ and we remain on the lookout for attractive opportunities, either in Botswana or the wider Southern African region.” Photos by Lucara Diamond Corp (unless otherwise credited)

shipped tonnes of Karowe ore up to Europe and did initial tests with graphite tracers, then – as we gained confidence with the technology – we introduced Karowe’s diamonds into the pro- cess, including a +200 carat stone! TOMRA was selected following a technical and commercial adjudication. The net result of the selection process is that we have a cost-effective technol- ogy that can obtain high diamond recovery at high throughput for all our ore types with mini- mal need for further sorting.” Once the upgrade is complete, Karowe will be able to maintain its annual production in the 400 000 to 450 000 carat range through to 2026. After that there is the possibility that the mine could transform into an underground operation and a preliminary desktop study on this option is being undertaken. Lucara is also embarking on an intensive pro- gramme of exploration in the Karowe area with the aim of identifying additional resources. It recently put in some “aggressive applica- tions” – as Dr John Armstrong, the company’s VP, Mineral Resources, puts it – for prospec- tive ground in the vicinity of the mine that was ‘on auction’ and was awarded two exploration licences, both of which host known diamond- iferous kimberlites, in September 2014. One of the licences, Block A, is located 30 km to the east of Karowe while the other, Block E, lies 15 km to the north of the mine. According to Armstrong, all the kimberlites were discovered by De Beers in the late 1960s, with some having been subject to further explo- ration in the intervening period since and others almost totally neglected. “Our intention is to bulk sample these kimberlites and – to this end – we’ve contracted ADP Projects of Cape Town to supply us with a 15 t/h bulk sample plant, which we will install at Karowe. If all goes to plan, we should be putting material through the plant in the third quarter of 2015,” he says. Karowe, of course, is not Lucara’s only asset

Detailed planning the key to success Leading the DRA teamon site on the Karowe upgrade as Construction Man- ager is Clint Jennings, who told Modern Mining that the contract was pro- gressing well.“The main challenge is that we’re having to handle some very complex construction in and around an operating plant, at the same time fitting in with the operational cycle,” he said. “The success of a ‘brownfield’ project is a function of how much planning goes into it at the beginning and I spent four months coming up here from Johannesburg prior to the project starting on site in March this year (2014) to ensure that we could achieve a good alignment of construction with operation.” DRA is managing a large contingent of sub-contractors and suppliers who include Basil Read subsidiary Sladden International, responsible for civils and earthworks, SMEI Projects, which is handling structural, mechani- cal, piping and plating work, and HVC, the electrical instrumentation con- tractor. The labour force deployed on site is due to peak at around 480.

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January 2015  MODERN MINING  55