Modern Mining March 2019

DIAMOND MINING

of these technologies, says the company. Commenting on the 2018 results, Clifford Elphick, Chief Executive of Gem Diamonds, said: “Gem Diamonds achieved a good set of results, characterised by the recovery of 15 dia- monds greater than 100 carats, a record for a single calendar year. Production in 2018 also included the highest recovery of diamonds greater than 20 carats, with 80 % of revenue primarily generated by diamonds greater than 10 carats. “The mine plan for Letšeng was revised dur- ing 2018, with the aim of further reducing the waste stripping through the steepening of inter- ramp slope angles. Mining in accordance with this plan has commenced and is expected to significantly increase the net present value of the mine. “The Business Transformation process has progressed well and remains on-track to achieve the target of US$100 million in cost savings and efficiencies by 2021. By December 2019, the initiatives already implemented are expected to deliver US$64 million to the end of 2021.” Photo courtesy of Gem Diamonds

Lesotho Legend , which ranks as the largest dia- mond ever recovered at Letšeng and the fifth largest gem-quality diamond recovered glob- ally. The trend for improved recoveries in 2018 was consistent across all size categories, with a 21 % increase from 2017 for the total number of diamonds recovered greater than 20 carats. During the year, Gem, through its subsid- iary Gem Diamonds Innovation Solutions, (GDIS), continued to make good progress in the development of its two key technologies to (i) identify locked diamonds within kim- berlite; and (ii) to liberate diamonds using a non-mechanical process. These technologies are aimed primarily at limiting diamond dam- age and reducing operating costs. The company approved a US$3,0 million pilot plant to be constructed at Letšeng which employs innovative technology to identify dia- monds within kimberlite ore. This project will also include the use of a prototype high-voltage pulse generating unit to liberate the diamonds. Gem anticipates that the pilot plant will be commissioned during Q2-2019. The results and outcomes emanating from the pilot plant opera- tion will determine the way forward in respect

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March 2019  MODERN MINING  37