Meteoric Resources NL (ASX:MEI) has demonstrated significant gold recoveries from its metallurgical test-work program on Composite #2 (Tranche 2) at the Butchers Creek Gold Deposit within the Palm Springs Project in Western Australia.
The most important outcome from all the test-work is the high leach recovery of gold achieved on straight 'Whole of Ore' leaching, which indicates the gold is well liberated and not locked up or influenced by the presence of moderate amounts of sulphides.
Notably, the 'Whole of Ore' leach tests produced the highly encouraging recovery of 95-96% gold after a leach time of only 24 hours.
Akin to Composite #1, the results from Composite #2 confirm a simplified flowsheet requiring either a potential low-cost treatment facility or ore which is also amenable to toll treatment
“Outstanding results”
Meteoric managing director Dr Andrew Tunks said: “The metallurgical test results from Composite #2 again produced outstanding results that confirm a low cost, simple 'whole of ore' flowsheet using cyanide in leach (CIL) is suitable for Butchers Creek gold-rich ore.
“These results will be fed into the current scoping study which is due for release to the market in the current quarter.”
Metallurgical test program
Meteoric’s continued test-work highlighted straightforward non-refractory metallurgical ore characteristics, with a likely processing route incorporating a simple industry-standard CIL cyanide leach plant.
The measured physical properties indicate a weak to moderately hard ore which would not pose issues in terms of the design or selection of conventional crushing and grinding equipment.
Each composite was formulated at ALS Laboratories in Perth from half HQ core sent from the site, with all test-work carried out under the supervision of Trinol Pty Ltd in Perth.
Prior to compositing, half-core samples were set aside to measure the physical characteristics - UCS, Crushing Index (CWi) and Ball Milling Index (BBMi).
Head samples were examined by XRD to gauge the extent of sulphide minerals present, then subjected to the following standard test regime:
- Grind establishment;
- Gravity followed by direct cyanide leach;
- Gravity recovery followed by flotation, ultra-fine grinding to 10 microns of the concentrate and leaching of the tailings; and
- Whole of ore leaching.
Forward plan
The next phase of evaluation will be to use these results as a basis for a scoping study based on a fit for purpose CIL plant and associated mining and infrastructure at Butchers Creek.
Additional test-work will be undertaken to see if these recoveries can be improved with extra cyanide residence time as suggested by Composite #2 results.
Furthermore, Meteoric will take a closer look at the extra capital and operating cost of gravity and flotation as the development of Palm Springs continues.