Medallion Metals Ltd (ASX:MM8) has confirmed consistent, high metallurgical recoveries for gold, copper and silver from ongoing metallurgical studies at its flagship Ravensthorpe Gold Project (RGP) in southern Western Australia.
The metallurgical review, undertaken by GR Engineering Services Limited (GRES), was aimed at confirming the preferred processing route to maximise gold, copper and silver recovery from RGP’s ores.
Consequently, GRES has concluded that the industry-standard, conventional Gravity-Flotation-Carbon in Leach (CIL) route is the preferred option to maximise recoveries from RGP ores to saleable products, in the form of gold dore and copper or precious metal concentrates.
Looking ahead, Medallion will update gold, copper and silver resources as part of a new mineral resource estimate (MRE) for RGP expected to be announced in April 2022.
“Important step”
Medallion Metals managing director Paul Bennett said: “The completion of the metallurgy review is an important step for Medallion to both consolidate the significant amount of work done and to plan for the future.
“We’re pleased to have an industry leader in GR Engineering assist us in this regard.
“The outcomes of their work demonstrates high gold and copper recoveries can be consistently achieved using industry-standard processes across lithologies and deposits which has the potential to improve project returns by unlocking the value of the by-products.
“The review findings will assist us in planning the next and final round of metallurgical test-work for RGP, in addition to supporting the upcoming resource update expected in April.”
Metallurgical test-work
Medallion has engaged GRES to conduct a review of all metallurgical test-work undertaken on RGP ores. Subsequently, this work provided a substantial database for the GRES metallurgical review.
Notably, estimates of metal recoveries, concentrate grades and reagent consumptions under the preferred process route are other key outcomes of the review.
Furthermore, the scope also included a gap analysis to identify any additional metallurgical test-work which may be required to support a definitive feasibility study (DFS) level of assessment of the technical and commercial viability of RGP in the future.
Findings
Medallion’s estimates of metal recoveries and its deportment into saleable products are:
- Gold - 94.6%;
- Copper - 86.1%; and
- Silver - 73.3%.
Gravity-Flotation-Carbon in Leach (CIL) has been determined as the ideal process route to maximise gold, copper and silver recovery from RGP’s ores.
GRES recommended that additional test-work be performed to confirm the potential for use of coarser grind size and to ensure representativity from areas of expected resource growth.
Forecast recoveries to saleable products.
Forward plan
As a result of the GRES review confirming the potential for high recoveries of gold, copper and silver to saleable products, Medallion will estimate gold, copper and silver as part of the MRE update for RGP.
While gold is the dominant driver of project economics, unlocking the value of copper as a significant by-product credit has the potential to materially enhance project returns.
Medallion has commenced a sighter round of exhaustive leach tests on 19 samples from the Gem Restored deposit and the Ariel and Meridian prospects.
Furthermore, preparations are also underway for the collection of samples for the additional test-work recommended by GRES.