Platreef mine is a major platinum-group-metals (PGM) and base metals underground mine being developed by Ivanplats. The mine is located approximately 280km north-east of Johannesburg, in the Limpopo province of South Africa.
Ivanplats (formerly Ivanhoe Nickel & Platinum) is a joint venture led by Ivanhoe Mines, which holds 64% interest in the project.
BBBEE SPV, a broad-based, black economic empowerment entity including local communities, employees and entrepreneurs, holds 26% stake in the project, while the remaining 10% is owned by a consortium of Japanese companies including Itochu Corporation, Japan Oil, Gas and Metals National Corporation (JOGMEC), and Japan Gas Corporation (JGC).
The Platreef platinum mine is expected to commence initial production of four million tonnes per annum (Mtpa) in 2022, which will be ramped up to 8Mtpa in the second phase and 12Mtpa in the third and final phase.
Platreef is anticipated to be the lowest cost producer of PGMs in Africa.
Platreef project development details
South African Department of Mineral Resources (DMR) granted mining right for the project for an initial period of 30 years, in May 2014.
Construction of the 7.25m-diameter Shaft-1 for initial access and early underground development of the mine started in 2014.
The Shaft-1 reached the top of the high-grade Flatreef Deposit at a depth of 780.2m below surface in October 2018.
Early construction works for the Shaft-2 began in May 2017 and are expected to be completed in 2019.
With a diameter of 10m, Shaft-2 will be the main production shaft capable of hoisting six million tonnes a year.
Ivanhoe Mines had released the feasibility study for the project in January 2015 and completed a definitive feasibility study (DFS) in July 2017.
The DFS predicted average annual production of 476,000 ounces (oz) of platinum, palladium, rhodium, and gold (3PE+Au), 21 million pounds (Mlb) of nickel and 13Mlb of copper over an estimated mine life of 32 years.
The pre-production capital investment in the project was estimated to be $1.54bn.
Geology and mineralization
The Platreef project targets the high-grade Flatreef deposit of average vertical thickness of 24m within the Platreef mineralized belt that forms part of the northern limb of South Africa’s Bushveld Igneous Complex (BIC).
The Bushveld complex is believed to host approximately 75% of the world’s platinum resources.
The Flatreef deposit has a strike length of six kilometers. Mineralization occurs at depths ranging between 700m and 1.1km below surface.
Platreef mine reserves
The Platreef mine was estimated to hold 125Mt of probable ore reserves grading 1.95 grams per tonne (g/t) platinum, 2.01g/t palladium, 0.30g/t of gold, 0.14g/t rhodium, 0.17% copper and 0.34% nickel, as of July 2017.
The indicated and inferred mineral resources at 3.0g/t cut-off grade (3PE+Au) were estimated to be 204Mt and 225Mt, respectively.
Mining and ore processing
Longhole stoping and drift-and-fill mining methods will be employed for extracting underground ore.
The underground mine will be accessed using four vertical shafts. The ore will be hauled from the stopes to the bottom of Shaft 2, where it will be crushed and hoisted to the surface, while Sshafts 1, 3 and 4 will be used for ventilation.
The run-of-mine (RoM) ore will pass through three-stage crushing, milling, flotation, thickening, and filtration circuit for the production of concentrates.
Infrastructure facilities for the Platreef project
The mine site will be accessed from Mokopane via a paved all-weather national highway. The Rietfontein and Bultongfontein sites are identified as the preferred tailings storage facility sites for the mine.
South African national power utility Eskom will provide power supply for the project.
Ivanhoe signed a 32-year-agreement for the supply of five million liters of treated water a day for the Platreef project, from the town of Mokopane’s new Masodi treatment plant, in May 2018.
DRA Global was engaged to prepare the DFS of the project, while OreWin, Amec Foster Wheeler, Stantec Consulting, SRK Consulting, Metallicon Process Consulting, and Geo Tail were engaged to prepare the preliminary economic assessment (PEA).
Aveng Mining was awarded the sinking contract for the Shaft-1 of the underground mine.
Murray & Roberts Cementation, a company based in South Africa, was awarded the design and engineering contract for the Shaft-2 in June 2014.