Name of the Project
Platreef palladium/rhodium/nickel/platinum/copper/gold project.

Location
Northern limb of the Bushveld Complex, about 11 km from Mokopane, in Limpopo, South Africa.

Project Owner/s
Ivanhoe Mines indirectly owns 64% of the Platreef project through its subsidiary, Ivanplats, and is directing all mine development work.

The South African beneficiaries of the approved broad-based, black economic-empowerment structure have a 26% stake in the Platreef project. The remaining 10% is owned by a Japanese consortium comprising Itochu Corporation; Japan Oil, Gas and Metals National Corporation; Itochu affiliate ITC Platinum Development; and Japan Gas Corporation.

Project Description
The 2022 feasibility study on the Platreef project has confirmed its potential to be the industry’s biggest and lowest-cost primary platinum group metals (PGMs) producer.

The  feasibility study is based on the detailed design and engineering scenario first presented in the November 2020 preliminary economic assessment, alongside the 2020 feasibility study, confirming the viability of a new phased development pathway to fast-track Platreef into production by the third quarter of 2024.

The 2022 feasibility study considers Phase 1 and Phase 2 development, including only one-third of Platreef’s indicated resources above an $80/t net smelter return cutoff.

The project has indicated mineral resources estimated at 18.9-million ounces of palladium, 18.7-million ounces of platinum, 3.1-million ounces of gold and 1.2-million ounces of rhodium (a combined 41.9-million ounces PGMs plus gold), as well as 2.4-billion pounds of nickel and 1.2-billion pounds of copper at a 2 g/t platinum, palladium and rhodium plus gold (3PE+Au) cutoff.

Platreef’s inferred mineral resources contain an additional 23.8-million ounces of palladium, 23.2-million ounces of platinum, 4.3-million ounces of gold and 1.6-million ounces of rhodium (a combined 52.8-million ounces PGMs plus gold), as well as 3.4-billion pounds of nickel and 1.78-billion pounds of copper, also at a 2 g/t 3PE+Au cutoff.

The 2022 feasibility study is based on steady-state production of 5.2-million tonnes a year, as well as an accelerated ramp-up to steady state through the earlier development of Shaft 2.

Phase 1 production at Platreef includes an initial 700 000 t/y underground mine and 770 000 t/y capacity concentrator, targeting high-grade mining areas close to the project’s recently completed Shaft 1.

Phase 1 average production is estimated at 113 000 oz/y of 3PE+Au, and five-million pounds of nickel and three-million pounds of copper.

While the 700 000 t/y initial mine is operating using Shaft 1, the sinking of the project’s second, larger, Shaft 2, which will drive the Phase 2 expansion to 5.2-million tonnes a year, will progress simultaneously.

Once Shaft 2 is complete, two 2.2-million-tonne-a-year concentrator modules will be commissioned, and the initial concentrator will be ramped up to its full capacity of 770 000 t/y, increasing the steady-state production to 5.2-million tonnes a year.

Platreef’s Phase 2 expansion will result in its ranking as the world’s fifth-biggest primary PGMs mine on a palladium equivalent basis, with forecast production of 591 000 oz/y of 3PE+Au, as well as 26-million pounds of nickel and 16-million pounds of copper a year.

The Platreef 2022 feasibility study reflects only the initial two phases of development for the mine. If the remainder of Platreef’s indicated resources were to be converted to reserves, it would provide an opportunity to massively expand production.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The 2022 independent feasibility estimates an after-tax net present value, at an 8% discount rate, of $1.7-billion and an internal rate of return of 18.5% at long-term consensus metal prices. Payback is estimated at 7.9 years.

Capital Expenditure
Initial capital costs for Phase 1 are estimated at $488-million.

Expansion capital for Phase 2 is estimated at $1.5-billion, which may be partially funded by cash flows from Phase 1 and a project financing package.

Planned Start/End Date
First concentrate production for Phase 1 is planned for the third quarter of 2024; the Phase 2 expansion, based on the commissioning of Shaft 2, in 2027; and the commissioning of two 2.2-million-tonne-a-year concentrators in 2028 and 2029. 

Latest Developments
Murray & Roberts Cementation will repurpose Ivanhoe Mines’ 3 Shaft – a ventilation shaft – to serve a dual function. The shaft will hoist ore while allowing for upcast air to reach surface.

The project has followed for the sinking of the vent shaft by Murray & Roberts Cementation. The 5.1-m-diameter shaft meets horizontal development at a depth of 950 m below surface.

Among the range of technical challenges is the need to work within the vent shaft while it is performing its function of channelling an upcast current of air to surface. Any blockage of the air current in the shaft would affect the development operation of the mine, so this is critical to avoid.

It will be necessary to deal with the slight deviations in the shaft and, while accurately drilled, vent shafts are not designed to the same tolerances as hoist shafts, Murray & Roberts Cementation new business director Graham Chamberlain has pointed out. An important aspect of the design is the steelwork required to accommodate those deviations.

The infrastructure will employ technology that will allow for operation without people to enhance safety using automated processes in loading and measuring functions, for instance.

The project will require specialised subcontractors for much of the equipment, but the more day-to-day consumables are procured locally to support local businesses.

Key Contracts, Suppliers and Consultants
OreWin – Australia (overall report preparation and economic analysis, mineral reserve estimation and mine plan); Mine Technical Services – US (mineral resource estimation); SRK Consulting – South Africa (mine geotechnical recommendations); DRA Global – South Africa (process and infrastructure); Golder Associates Africa – South Africa (water and tailings management); Murray & Roberts Cementation (ventilation shaft sink and shaft repurposing).

Contact Details for Project Information
Ivanhoe Mines, tel +27 11 088 4300 or email info@ivanhoemines.com.