Theta Gold Mines to Restart Operations at Historic Mines in South Africa
The Australia-based company will extract the precious mineral in the Mpumalanga area.
Theta Gold Mines will restart the gold mining process at the Transvaal Gold Mining Estate (TGME) in Mpumalanga Province, South Africa.
The extraction of resources is expected from the Beta (Beta North, Beta Central, and Beta South sections), Rietfontein, Frankfort, and Clewer-Dukes Hill-Morgenzon (CDM) mines. These mines were not developed earlier because of technological limitations and limiting ore characteristics.
The project in the Mpumalanga Province, a historic gold mining region, is approximately 370 kilometres northeast of Johannesburg and centred around the town of Pilgrims Rest.
TGME lies within the Sabie-Pilgrims Rest Goldfield, which extends across 140 kilometres in a north-easterly direction. It has a maximum width of 30 kilometres along the Great Escarpment of southern Africa. It contains 43 historical gold mines covering an area of 620 square kilometres.
A trial mining took place at Frankfort in December 2021, and project feasibility studies were completed in July 2022. The estimated life of mine (LoM) is 12.9 years, and it will be capable of producing 1.08 million ounces (Moz) of gold from 1.24 Moz of mined gold. The capital investment required will be US$174.3 million.
Theta Gold Mines Chairman, Bill Guy, comments on yesterday's announcement regarding the extension of its Underground Prefeasibility Study (PFS).— THETA GOLD MINES (@ThetaGoldMines) January 14, 2022
Theta has added Rietfontein Mine to the mine schedule of the PFS.
Read announcement: https://t.co/8mnZjOQv07 pic.twitter.com/8Sr3WZuHkb
Construction is expected to begin in December 2022, and the first production of gold is expected by the second quarter of 2024. The projected rate of gold ore production is 160,000 oz a year within five years in a phased manner.
Theta Gold Mines’ technical team and independent consultant Minxcon conducted feasibility studies for the project and provided mineral resource estimates in February 2021. Met63, an engineering company, was contracted to provide the design for the processing plant.
Paterson & Cooke Consulting Engineers conducted a pre-feasibility study report on the underground deposition of tailing material, and Digmin provided trial mining operations.
Mining operations are scheduled for Beta, followed by Rietfontein, and then at CDM and Frankfort simultaneously. Beta, Frankfort, and CDM will employ mining operations via mechanized long-hole drilling to narrow reef mining to mine only the reef channel with minimal dilution selectively.
Existing mining infrastructure will be used, adding new accesses, underground development, and pre-development of mining grids at Beta, Frankfort, and CDM.
Rietfontein will use conventional mining methods through shrinkage stopping with hybrid loading methods, including trackless load-haul dumpers (LHDs) and rail-bound locomotives.
An ore treatment facility will also be established approximately 40 kilometres from the project site. It will be developed in three phases:
- Phase 1 will involve a 45,000 tonnes per month (TPM) oxide ore processing plant comprising crushing, milling, carbon-in-leach (CIL), and elution circuit to produce doré on site. It will also have a flash flotation stage for removing sulphide-associated material before cyanidation.
- Phase 2 will have a 20,000 TPM gold concentration plant, including crushing, milling, dense media separation (DMS), and flotation circuits. It will produce combined carbon and sulphide flotation concentrate.
- Phase 3 will include a 45,000 TPM leach-ox process plant, including crushing, milling, and carbon/sulphide flotation. There will be a gold concentrator plant and the CIL plant from Phases 1 and 2.
A dedicated CIL (CIL 3) circuit will process the carbon flotation concentrate. Sulphide flotation concentrate will be oxidised with liquid oxygen and high sheer reactors. The oxidised product will then be treated in batches at CIL 1, while tails will be treated in CIL 2. This will enable on-site doré production from the recovered gold with no concentrate.
The Phase 1 plant will be constructed first to treat CDM, Rietfontein, and Beta ore, while Phase 3 will be developed before mining begins at Frankfort.
Top Photo: Trial mining at Frankfort Mine (thetagoldmines.com)