Name of the Project
Prieska copper/zinc project.

Location
The project is located in the Northern Cape, in South Africa.

Project Owner/s
Orion Minerals.

Project Description
An updated bankable feasibility study (BFS) has confirmed the potential of the Prieska project to underpin a significant near-term, low-cost, copper/zinc development project, with exceptional opportunities for future growth.

The project has total mineral resources of 30.49-million grading 1.2% copper and 3.7% zinc.

The updated BFS on the foundation phase of the project proposes the development of a new 2.4-million-tonne-a-year copper/zinc mining operation at the brownfield project.

Underground and surface mining methods are planned to be used in conjunction with con­ventional froth-flotation concentration to produce differentiated copper and zinc concentrates for export.

Peak production is estimated at 23 000 t/y of copper and 88 000 t/y of zinc.

The life-of-mine has been extended by two years from 9.7 years to 11.5 years.

Material changes in the updated BFS, compared with the 2019 BFS plan, include:

• reducing the mine dewatering timeline and sup­plementing the treatment of that water,

• incorporating additional mineral resources into the mining plan that will increase the mine life by two years,

• a more conservative timeline to ramp up to steady-state production,

• prioritising early mining of the high-grade zones in the mining sequencing,

• the adoption of semiautogenous grinding mills in the processing flowsheet,

• an owner-miner operating philosophy for under­ground mining,

• using an experienced contractor to operate the processing plan, and

• a change in the key operational infrastructure being supplied by third-party financing and in the supply of select key operational infrastructure.

The mining methods for the project remain unchanged, compared with those stated in the 2019 BFS. Tunnel development remaining from the previous mining operations allows for early access to underground production mining areas. A combination of longhole open stoping with fill and drift-and-fill mining methods are planned to be used, supported with paste backfill.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
The project has a net present value, at an 8% dis­count rate, of A$779-million, compared with A$574-million in the 2019 BFS, and an internal rate of return of 39%, compared with 38% in the 2019 BFS. Payback from first production is estimated at 2.4 years, a decrease of five months.

Capital Expenditure
Total startup capital, including contingency, has decreased from A$400-million in the 2019 BFS to A$373-million in the updated BFS.

Peak funding requirements have increased from A$378-million in the 2019 BFS to A$413-million.

Planned Start/End Date
Orion Minerals is targeting a production startup in 2024, market conditions permitting.

Latest Developments
Orion Minerals has reported massive copper and zinc sulphide intersections at two near-mine prospects at the Prieska project.

The miner has said that drilling at the Kielder prospect, about 15 km from the planned mill, intersected the mineralisation.

“This is a clear demonstration of the enormous exploration upside around the proposed Prieska copper/zinc mill, which offers opportunities to extend the mine life and grow our production profile in the future,” Orion MD and CEO Errol Smart has said.

He adds that, based on visual observations, the intersections are geologically similar to those at the main Prieska copper/zinc deposit and occur at very shallow depths, which bode well for their future economic potential.

Key Contracts, Suppliers and Consultants
Companies involved in the BFS included: A&B Global Mining; ABS Africa; BPDT & Co; Bluhm Burton Engineering & Ventilation Consultants; Beulah Africa; Cart Investments; DRA Projects South Africa; Earth Science Solutions; Endeavour Financial Limited; Falcon and Hume Attorneys Inc; Fraser McGill Mining & Minerals Advisory; Knight Piésold; METC Engineering; Gariep Mining and Exploration Services; Mets Consulting South Africa; Patterson and Cooke; PCDS Consultants; Power Plant Electrical Technologies; Professional Cost Consultants; Promethium Carbon; Shift Innovations; SRK Consulting; Strategy4Good; The MSA Group; Turnkey Civil (International) Group; VBKom Engineering Consultants; Whittle Consulting; and Z Star Mineral Resource Consultants.

Contact Details for Project Information
Orion Minerals, tel +27 11 880 3159 or email info@orionminerals.com.au.