Positive Metallurgical Testwork In Western Mali
Altus Strategies Plc (AIM:ALS, TSXV:ALTS) has announced excellent results from metallurgical testwork on oxide and sulphide samples from the company’s 100 % owned Diba gold project in western Mali, The work was undertaken to test the amenability of Diba ores to carbon-in-leach (CIL) and heap leach processing.
Highlights:
- Excellent gold recoveries from oxide and sulphide samples:
- 98.3% recovery at moderate (75 μm) grind size on oxide sample for CIL scenario
- 86.8% recovery at moderate (75 μm) grind size of sulphide samples for CIL scenario
- 95.8% recovery at coarse (6.3 mm) crush size on oxide sample for heap leach scenario
Chief Executive, Steven Poulton,said the results will have a positive impact on the Diba PEA.
“The results of the metallurgical testwork on both oxide and sulphide material from Diba are simply excellent. Heap leach amenability shows 95.8 % gold recovery at a coarse crush size,” Mr Poulton said.
“This recovery is significantly higher than the 80 % modelled in the current PEA which we reported on in July. More significantly, the testwork on fresh (sulphide) samples shows that CIL processing will likely be very effective, with 86.8 % gold recovery at attractive grind sizes.
“Diba already boasts a robust US$81M post-tax NPV for the oxide ounces alone. The significantly enhanced recoveries and addition of the sulphide resource, should add considerable economic value to the Project. We have commissioned an updated independent PEA and look forward to reporting on the results in due course.
“Aside from the existing resource area, Altus has defined seven priority prospects at Diba, none of which have ever been systematically drill tested. These prospects are all located within 7 km of the current mineral resource, which itself is only 13 km from the multi-million ounce Sadiola gold mine. Altus is currently planning a drill programme for Diba and we look forward to providing an update on this in due course.”
The Company has engaged Mining Plus UK Ltd to update the existing Diba PEA to incorporate the higher oxide recoveries reported in this release (95.8 % compared to 80 % used in the existing PEA).
Mr Poulton said that importantly, the PEA will be broadened to model CIL processing to incorporate the current sulphide MRE of 33,600 ounces at 1.12 g/t Au Indicated and 153,300 ounces at 1.05 g/t Au Inferred . Incorporating the oxide and sulphide resource and using the higher processing recoveries is expected to have a materially positive impact on the current US$81m (post-tax) NPV as calculated under the existing PEA.
