Tharisa, the platinum group metals (PGMs) and chrome co-producer, announces an extension of the open pit Life of Mine (LOM) at its flagship Tharisa Mine, following an annual review of its Mineral Resource and Mineral Reserve statement. Open-pit tonnage increased by 30% to 94.2Mt with improvements in both 3PGE+AU and CR2O3 mineral content.
- The September 2021 Mineral Resource and Mineral Reserve statement for the Tharisa Mine indicates a significant extension to the LOM, increasing from 13 years to 20 years
- Open pit production will now continue until 2041
- The revised LOM schedule also mitigates the risks associated with the transition to underground mining, with portal development taking place as open pit mining continues
- Open-pit tonnage has increased by 30%, to 94.2 Mt, with total open pit and underground Mineral Reserves of 113.1 Mt at PGM grades of 1.09 g/t (3PGE+Au) and chrome grades of 18.6%, containing a total of 4.0 Moz PGMs (3PGE+Au) and a total of 21.3 Mt of chrome
Phoevos Pouroulis, CEO of Tharisa, commented: “Following an annual review of the Company’s Mineral Resource and Mineral Reserve, the Tharisa Mine’s open-pit mining will continue through to 2041, seven years longer than previously indicated. This development further cements the reputation of the Tharisa Mine as a world-class, long-life asset that underpins our business and will continue to provide a sustainable, low-cost platform for over 50 years.
This growth follows Tharisa’s demonstration of the consistency of its operations and proven ability to successfully move volume whilst maintaining a strong production profile, resulting in shareholder value accretion. The ability to extend the open pit at the Tharisa Mine also allows us to take further advantage of this unique asset and provides the platform for our growth strategy.”
2021 MINERAL RESOURCE AND MINERAL RESERVE INVENTORY REVIEW
The results of this review saw the Mineral Reserve tonnage increased by 15.6 Mt due to the final pit limit increase of the open pits. Pit design and updated MG chromitite layers accounted for a 26.4 Mt increase, mining depletion accounted for a 4.5 Mt decrease and the underground Mineral Reserves reduced by 6.2 Mt.
The variance between the 2020 and 2021 Mineral Reserve estimation is due to:
- Mining depletion
- Updated geological model and an updated coding of the MG Chromite Layers in the western pit area
- Updated open pit design based on the updated pit optimisation results
- Removal of a portion of the underground Mineral Reserves due to the increase of the open pit depths.
The open pit LOM schedule was based on a targeted ROM production rate of 5.64 Mtpa over a period of 15 years at which time the East open pit will be depleted and an additional five years for the depletion of the West pit, albeit at lower mining rates.
The final open pit ROM material will be produced during 2041. The open pit LOM increased by seven years due to the increase in the open pit limits. The East open pit transitions to underground mining from 2036 onwards and the West open pit from 2041 onwards.