Name of the Project
Cullinan C-Cut Phase 1 expansion programme.

Location
Gauteng, South Africa.

Client
Petra Diamonds (74%), Kago Diamonds (14%) and the Itumeleng Petra Diamonds Employee Share Trust (12%).

Project Description
The Cullinan mine contained a world-class resource base of 190.3-million carats as at June 30, 2018, which suggests that the mine could operate significantly longer than the current mine plan to 2030. The C-Cut Phase 1 project plans to capitalise on the mine’s resource base by undertaking an expansion programme that will treat between 3.7-million and  4-million carats a year by the 2019 financial year.

The project will establish a new block cave on the western side of the orebody, in the upper portion of the major C-Cut resource. It will also involve a large tailings retreatment operation.

The development plan will allow for the tonnage profile to gradually progress from the old mining areas, heavily diluted with waste rock, to the new mining areas, thereby providing access to undiluted ore.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
Not stated.

Value
R4-billion.

Duration
Steady-state production of four-million tonnes a year will be delivered from C-Cut Phase 1 and CC1E from the 2020 financial year onwards.

Latest Developments
The Cullinan mine's production increased 74% to an estimated 1.37-million carats in the 2018 financial year (2017: 786 509 ct), mainly owing to a 97% increase in run-of-mine (RoM) carat production as the new C-Cut Phase 1 block cave continued to ramp up and the new Cullinan plant operated at planned throughput rates. Production from the undiluted C-Cut mining areas, including CC1E, increased to about 2.46-million tonnes in the 2018 financial year (2017: about 1.2-million tonnes).

Petra is guiding for a range of 3.7-million tonnes to 4-million tonnes to be treated during 2019 financial year, owing to the continued ramp-up of C-Cut Phase 1, the depletion of the old B Block mining areas and the switch-over period required for the implementation of the new shaft/plant interface, which is scheduled to be completed by the third quarter of the 2019 financial year. This will alleviate constraints with the link between the underground hoisting system and the plant.

The C-Cut Phase 1 project is planned to contribute an estimated three-million tonnes for the 2019 financial year. A further 700 000 t to one-million tonnes will be sourced predominantly from the CC1E mining area, as well as from other B Block tonnes.  

Key Contracts and Suppliers
MDM Engineering, the South African division of Amec Foster Wheeler (Cullinan plant contract) and Murray & Roberts (Cullinan shaft contract).

On Budget and on Time?
The project is progressing well and in line with expectations.

Contact Details for Project Information
Petra Diamonds, email info@petradiamonds.com.