Lode Resources (ASX:LDR) has disclosed that laboratory metallurgical testwork on ore from its Montezuma Silver & Antimony Project in Tasmania has produced high-purity antimony metal cathode at 99–99.5% purity, with antimony recoveries of up to 95% achieved through leaching and electrowinning processes.

Key Points

  • Laboratory leaching and electrowinning achieved antimony recoveries of up to 95% and produced a smooth, high-purity cathode at 99–99.5% antimony from Montezuma ore
  • Rougher flotation upgraded the antimony leach feed to 4.08% antimony with 98.2% recovery while rejecting over 40% of the mass
  • Initial flotation testwork on Maestries silver-zinc-lead mineralisation achieved rougher recoveries of 97.6% zinc, 93.9% silver, and 92.8% lead
  • Current phase drilling at Montezuma is complete, with an updated mineral resource estimate anticipated in December; Pitch Black Group has been appointed to provide engineering, cost and process design for the scoping study
  • Discussions are advancing with potential offtake partners on an initial 100-tonne direct shipping ore shipment from high-grade, near-surface resources

Metallurgical Testwork Results and Flowsheet Confirmation

According to the filing, testwork samples were derived from HQ diamond drill core from twinned drillholes adjacent to resource drill holes MZS15 and MZS16. The testwork involved crushing, screening, ore sorting, flotation, antimony leaching and electrowinning, and flotation of post-leach residue. A pre-leach concentrate was produced that rejected over 40% of the mass while retaining 98% or more of the silver, antimony, copper and lead, 89% of the gold and 70% of the tin. Atmospheric alkaline leaching of antimony achieved up to 95% recovery, with lead returning to the residue as galena. Electrowinning produced a smooth cathode with purity in the 99–99.5% range.

Post-Leach Flotation and Maestries Mineralisation Results

The filing states that leach residue has been found to be amenable to upgrading by flotation, with laboratory testing continuing at ALS Metallurgy Burnie on a preferred flotation regime to maximise residual metal recoveries and product saleability. The company disclosed that the post-leach flotation testwork is currently focused on producing a bulk concentrate containing relatively high levels of copper, tin, silver, gold and lead for sale. Separately, initial flotation testwork on the replacement-style silver-zinc-lead mineralisation at Maestries demonstrated that the sulphide mineralisation floats well, achieving rougher recoveries of 97.6% zinc, 93.9% silver and 92.8% lead.

Resource Update, Drilling Activity and Scoping Study Progress

The filing states that the current phase of drilling at Montezuma is now complete, with an updated mineral resource estimate anticipated in December. Drilling activity in Tasmania is continuing at Fahlore using Lode's own diamond drill rig. Drill permits have been granted for Silver Cliffs and Persic, where the company has recorded silver grades of up to 9,370 grams per tonne. The company disclosed that a mineral resource estimate was announced in April 2026, based on 37 diamond holes completed to January 2026. Pitch Black Group has been appointed to provide all engineering, cost and process design elements of the scoping study, which the filing states continues to progress.