Cullinan Mine

Delivering reliable production

Petra has operated Cullinan Mine since 2008 and, through significant capital investment, has turned it from a loss making entity to the world class diamond mine that it is today. Current production uses a block-cave mining method, which is efficient and low cost. Through the installation of a new plant, the application of the latest processing technology and by using highly technical mining methods in accordance with the mine’s various geological technicalities we maximise the value of this unique asset.

Current production and future potential

The current source of Cullinan Mine’s diamonds are from the C-Cut section, which produces some of the world’s most exceptional diamonds. We also have two development projects approved, the C-Cut Extension and CC1-East, which will increase carat production markedly, improve grade and product mix and extend the mine plan.

Cullinan Mine is a world class resource, with potential to continue into the late 2040s.

Optimise

Current mining: C-cut

• Block cave mining
  • Sole source of production until development projects contribute from end-FY25
  • Re-opening tunnel T41 to underway
• Regular producer of high value Type II stones

Optimise

Development projects: Approved mine plans

1. Complete development of CC1-E

2. Complete development of C-Cut extension 1 & 2

Total extension capital for FY 2026 – FY 2030 is expected to be US$148-160 million. This includes provision for CC1 East, C-Cut
Extension 1 & Extension 2 and associated infrastructure

 

 

Develop

Long term potential

Beyond FY 2030, Cullinan Mine has significant potential, with a further c. 8.5 Mcts that can be mined from the CC1E Phase II and
C-Cut Extension 3 orebodies.

The D-Cut provides life of mine extension potential to beyond 2040 – this is not included in current detailed LOM planning and subject to further feasibility work and approval

 

Valuing our people

Our community training and development programmes build skills within host communities that benefit both local residents and our operations. The programmes provide us with accessible talent while driving social and economic development in these communities.
In FY 2025, we invested US$0.2 million (FY 2024: US$0.2 million).

We also supported seven students through bursaries (FY 2024: 13). Among these bursary holders, 43% are women and 86% are HDSAs. Two of the bursars studied social welfare and one was subsequently employed by the Department of Social Welfare in Koffiefontein.

Cullinan Mine employs ca. 2,200 employees and contractors. Given the generally accepted x10 multiplier effect, this means ca. 22,000 people in the surrounding community are dependent on the mine.

Let’s Do No Harm:

In FY 2025 Cullinan’s Lost Time Injury Frequency Rate per 200,000 hours worked was 0.47 (FY 2024: 0.22).

Health and wellbeing:

In addition to primary healthcare and occupational health services, Petra has an extensive wellness programme to prevent, identify, monitor and support employee illnesses and conditions. 6,345 medical examinations were carried out in FY 2025 across the Group.

Shared value partnerships

Local Procurement

c. 100% of procurement spend is with local suppliers at our South African operations.

Community and social investment

Petra considers providing training, education and development to local community members just as important as training its own workforce, enabling economic uplift and provide potential job opportunities.