The Prieska Copper Zinc Mine (PCZM) is the flagship project in our future-facing metals portfolio, and will take us from explorer to producer. Historically mined between the 1970s and 1990s, PCZM is one of the world’s top-30 volcanogenic massive sulphide (VMS) base metal deposits. First production is expected within a year of financing.

Project details

Where is Orion Minerals’ Prieska Copper Zinc mine located and what infrastructure is available?

PCZM is in the Northern Cape Province of South Africa, 270km south-west of the regional capital Kimberley. Importantly, the mine has access to significant local and regional infrastructure, including:

• Sealed access roads to the project site
• 50km via bitumen road to existing rail siding
• Four high-voltage regional lines linked to the national electricity grid
• Road and rail links to major, bulk commodity and deep-water ports
• Bulk water pipeline supplies the site from the Orange River with all-year-round pumping capacity
• Low environmental sensitivity – existing disturbed/rehabilitated mine footprint

What Mineral Resources support long‑term value at the Prieska Copper Zinc Mine?

PCZM contains a globally significant VMS resource totalling 31Mt at 1.2% Cu and 3.6% Zn, including Indicated Mineral Resources of 20Mt at 1.22% Cu and 3.47% Zn and an Inferred Mineral Resource of 11Mt @ 1.2% Cu and 3.9% Zn  (refer to the ASX/JSE release 28 March 2025). Probable Ore Reserves at PCZM total 15.6Mt at an average grade of 1.1% Cu and 3.1% Zn, resulting in 164kt of contained Cu and 458kt of contained Zn. Mineral Resources remain open in some areas and this is supported by down-hole geophysics.

What underpins the Prieska Copper Zinc Mine’s development?

To capitalise on the positive near-term outlook for the base metals market, Orion released its Definitive Feasibility Study in March 2025 (refer to the ASX/JSE release 28 March 2025) outlining a two-phased development strategy aimed at de-risking the development pathway and fast-tracking value-creation.

The plan is designed to accelerate revenue generation and potentially reduce the upfront external peak funding requirements by phasing the mine build while retaining the ability to scale up to a full-scale project as sufficient funding becomes available.

The Uppers Phase – This phase is based on mining near-surface supergene sulphide ore in the crown pillar, which is accessible from an existing decline.  First production is expected 13 months after the start of construction and would continue for 4.3 years.

The Deeps Phase – This phase will commence simultaneously, starting with the completion of mine de-watering, refurbishment of the main shaft and construction of the mining infrastructure.

Mining of the Deeps has a life of mine (LoM) of 11 years and will overlap with the last 2.2 years of the Upper-Level mining. This gives a combined LoM of 13.2 years.

What did the early production plan and trial mining at the Prieska Copper Zinc Mine entail?

Trial mining took place over seven months at PCZM with a development mining team testing mining efficiency and making preparations for future, longer-term mining operations in the Uppers. The trial mining was also aimed at confirming geological contacts, distribution of mineralisation across the zones and confirming the forecast Cu and Zn grades. These results optimised the mine planning for the Uppers.

Mining the Uppers upfront offers the potential advantage of earlier concentrate production and allows for dewatering to be undertaken at lower pumping rates and concurrently with early revenue generation.

A revised underground mine sequence was developed to extract the supergene sulphide zone at the +105 Level, which currently sits above the accumulated water level (the Uppers). Extraction of the +105 Level Mineral Resource was originally planned to occur at the end of the mine life using open-pit mining.

Feasibility studies included the use of backfill, which opens the opportunistic potential for the extraction of the mineralised pillars left behind from previous mining and located above the accumulated water level. Production from the remnant pillars, if evaluation results are positive, could supplement the early mining Upper Phase.

What does the Prieska Copper Zinc Mine’s project funding entail?

Glencore binding agreement

Orion has signed a US$250m Prepayment Facility with Glencore linked to the sale of bulk copper and zinc concentrates from PCZM in 2026 (refer to the ASX/JSE release 09 February 2026). For the latest update, see our June 2026 Quarterly Report.

Industrial Development Corporation (IDC) equity conversion

Subsequent to early development funding arrangements, the Industrial Development Corporation of South Africa Limited (IDC) agreed to convert its ZAR250 million senior secured convertible loan facility into equity in Orion’s subsidiary, PCZM HoldCo. This conversion strengthens the PCZM balance sheet, reduces project debt and aligns the IDC as a long‑term equity partner as Orion advances toward construction and operations.

Learn more in our ASX/JSE release on 2 April 2026.

Early Development Strategy and funding framework

Orion’s Early Development Strategy was underpinned by a ZAR250 million senior secured convertible debt facility from the IDC, together with two funding instruments secured from subsidiaries of Triple Flag Precious Metals Corp. These included an A$10 million early funding arrangement to support trial mining and dewatering, and a US$80 million precious metals streaming agreement available for the development of commercial operations, subject to completion of a revised bankable feasibility study and securing sufficient development finance.

Orion fulfilled all conditions precedent to the IDC facility and the Triple Flag early funding arrangement, enabling the submission of drawdown notices for an initial combined drawdown of ZAR167 million (~A$13.8 million) (refer to the ASX/JSE release on 17 July 2023).

Key financial outcomes

• Net Present Value (NPV) (at an 8% discount rate) of:
  • Pre-tax: AUD797 million (ZAR9,966 million)
  • Post-tax: AUD568 million (ZAR7,105 million)
• Internal Rate of Return (IRR) of 31% pre-tax (26% post-tax)
• Payback period from the start of construction of 5.8 years
• Peak funding requirement of AUD578 million (ZAR7,230 million)
• Total project capital expenditure (including contingency) of AUD607 million (ZAR7,592 million)
• Capital intensity of USD9,174/t annual copper equivalent production, to achieve nameplate annual Cu production of 22ktpa and Zn production of 65ktpa
• All-in-sustaining costs of USD4,550/t (USD2.06/lb) of copper equivalent metal sold
• All-in-sustaining cost net of by-product credits of USD2,359/t (USD1.08/lb) of payable copper sold

Will exploration at the Prieska Copper Zinc Mine continue?

Orion sees the potential to define a major new VMS camp in the region surrounding the PCZM deposit, with near-mine exploration programs delivering a series of compelling new targets.

These include the emerging Ayoba VMS discovery, located 5.3km south-west of PCZM, where the discovery drill hole intersected 9.5m of massive sulphides grading 0.63% Cu and 0.93% Zn, including 1.50m at 0.89% Cu and 4.98% Zn. (refer to the ASX/JSE release 28 November 2018).

Ayoba represents the first new VMS discovery in the Areachap Belt in over 36 years and highlights the enormous upside over and above the large, high-quality Mineral Resource already defined at PCZM.

Geophysical surveys have also identified numerous compelling targets for both VMS-style copper-zinc mineralisation and nickel-copper sulphide mineralisation within a 15km radius of PCZM.

VMS deposits generally occur in clusters in proximity to one large or giant deposit and often comprise two or three medium-sized deposits and five or six smaller deposits.

Despite PCZM being one of the single largest VMS exhalative bodies known in the world, the area around the deposit has had virtually no exploration in over 36 years. Now, with the application of advanced, modern geophysics and the latest geological thinking, Orion can vector into targets which offer outstanding opportunities for new VMS discoveries.