Modern Mining January 2017

ZINC

Phase 2 of Gamsberg, which is mainly con- ceptual at this stage, would take capacity up to 10 Mt/a and would cost between US$300 and US$350 million. It could include a dedicated refinery, in which case the total investment could be in the region of US$800 to US$900 million. Construction of Gamsberg is starting to look like an inspired move on Vedanta’s part, given how the zinc price is moving. Early in 2016 it hit a five-year low of US$1 444/tonne but has since recovered to more than US$2 600/tonne (as of early December 2016). As Naidoo points out, the long-term outlook for the metal is good

mining methods and the resource is sufficient to support mining for many years. We’re going to undertake development in phases, with Phase 1 – which will only exploit a quarter of the entire resource – being an operation processing 4 Mt/a of ore to produce 250 kt/a of metal in concen- trate over a mine life of 12,5 years.” An interesting point is why Anglo never went ahead with the development of Gamsberg. Says Naidoo: “Anglo contemplated a very large scale, almost megapit-sized, 10 Mt/a operation with a refinery also being part of the development plan. This would have involved a very high capex in one go. Our approach is to tackle the project in more manageable steps. We looked at 2, 4 and 6 Mt/a options before settling on the intermediate figure of 4 Mt/a. “Another factor that makes this project so suitable for us is that we are integrat- ing the refinery at our Skorpion mine in southern Namibia into the development plan. At least a portion of Gamsberg’s concentrate will be trucked to the Skorpion refinery, which can handle the high manganese fraction. Of course, we will have to upgrade the Skorpion facility, originally designed for oxide concentrates, to allow it to treat the sul- phides from Gamsberg and this involves a capex of US$152 million. Skorpion was due to close as a result of the ore reserves being exhausted but Gamsberg gives it a considerable extension of life.”

Mining operations at Gamsberg. The haulers seen are BELAZ 130-t electric trucks operated by Roux Mining.

Quiver trees have been relocated as part of the Gamsberg project’s commitment to the biodiversity of the region.

January 2017  MODERN MINING  57