LARGER (SULPHIDE) MINE DEVELOPMENT
The Sulphide Development Project, in which the ‘sulphide ore’ encompasses approximately 90% of the Buckreef Main Zone’s 2M oz Au Measured and Indicated Mineral Resources1, is a key value driver for the Company. Unlocking this value is an important objective for the Company.
The Sulphide Development Project will evaluate the options for a high return large scale project. It is the goal of the Company to exceed all metrics as outlined in the Technical Report, including annual production and strip ratio. We continue to work with our principal consultants on advancing the Sulphide Development Project. To date, Buckreef Gold has commenced a number of long-lead items for de-risking of the Sulphide Development Project. For one, geotechnical characterization is underway to determine the ultimate pit slopes of the 2 km long open pit, which commenced in Q2 2022 with consultants SGSC and Terrane Geoscience. Variability metallurgical studies are also underway for the first 5-7 years of potential production of the Sulphide Development Project. To date a total of 19 metallurgical holes (2,367 meters) have been completed along the entire strike of the Buckreef Main deposit and the holes have been logged and are in preparation for shipment for metallurgical testing.
The Company, in conjunction with Ausenco, has finalized locations for the Sulphide Processing Plant, Dry Stack Tailings Facility, Waste Rock Piles and other infrastructure. All locations are subject to successful ‘condemnation drilling.
An exploration drilling program will also focus on infill drilling at Buckreef West, Inferred mineral resources and strike extensions, which if successful, has the potential to increase tonnes to the Indicated mineral resource category and add, if economic, to the mineral Reserves category.
The Company is currently in discussions with various technical firms with regards to updating past technical studies with the goal of establishing a new vision for the Buckreef Gold Project.
1 See Disclaimer and Cautionary Note section of the website.
ADVANCING TECHNICAL WORK IN 2023
In June of 2023, TRX Gold announced important preliminary results from bulk sample testing at the Buckreef Gold mine. Over 6,500 tonnes of sulphide ore were successfully processed through Buckreef Gold’s existing milling facility, achieving an indicative gold recovery of 88.7%. This is a significant achievement as approximately 90% of Buckreef Gold’s 2M oz Au mineral resource is held in sulphide material, thus unlocking the significant economic potential of the project. This bulk sample test indicates that the Company can process sulphide ore through its existing processing plant, thus minimizing capex for future plant expansions.
PAST TECHNICAL WORK SUPPORTING MINE DEVELOPMENT
In 2020, three diamond drill holes were completed for the purposes of initial, modern era metallurgical test work. The samples were extracted as fresh drill core from areas/zones with known lithologies from within the current project’s open pit limit. The samples were selected by TRX Gold and confirmed by the SGS geological services group that worked together doing the metallurgical sample selection. The investigation included ore characterization, comminution, mineralogy, head analyses, and potential for gold preg-robbing, and evaluated the amenability of the three samples to two primary processing flowsheet options, that incorporate comminution (crushing and grinding), gravity separation, flotation and cyanidation unit operations.
Results from this test work, include several important highlights:
✓ Excellent gold recoveries
✓ A straight forward flowsheet consisting of:
- Primary grinding to P80 = ~100-150 µm
- Rougher flotation
- Regrind of the rougher concentrate to ~15-20 µm (P80)
- Cyanide leaching of the reground flotation concentrate
- Cyanide leaching of the flotation tailing
✓ No refractory association of gold with arsenic sulphide was detected;
✓ The samples tested did not exhibit any preg-robbing or other refractory characteristics;
✓ Clean tailings, high probability of mine tailings not being acid generating, confirming the approach of dry stack tailings going forward
✓ Further opportunities to improve gold extraction from MC03 have been identified through diagnostic leach testing
Further testing is scheduled to take place to analyze for:
- Overall gold recoveries
- Process design to achieve those recoveries (grindability, retention times, straight CIL or flotation/regrind)
- Any pregnant solution robbing or refractory mineralogy
- Acid Mine Drainage (if any) characteristics
- Dry stack tailings characteristics.
The Company, along with its Owner’s Engineers (Ausenco and Solo Resources), are currently in a procurement process for this work.
Sulphide Sample Flowsheet
