Panther Metals (PALM) has reported encouraging Phase 1 metallurgical testwork at its Dotted Lake project in Ontario, Canada, with magnesium recovery reaching about 38% from serpentine-rich ultramafic material.
The testwork evaluated the applicability of Extrakt leaching technology as an alternative to conventional magnesium extraction methods.
The Phase 1 tests achieved cumulative magnesium recovery of about 38%, substantially above the 19-25% recovery ceiling observed during conventional single-stage leaching due to silica passivation.
Panther said the results confirm Dotted Lake's ultramafic intrusive as a magnesium-rich serpentine feedstock, with the material also containing elevated concentrations of chromium, nickel, cobalt and other critical elements that could potentially be recovered as by-products.
The company submitted 134 kilograms of crushed serpentinite drill core from its 2024 drilling programme for the investigation. The material comprised 60 samples from drillholes DL24-002 and DL24-004, which were combined into three composite samples designed to represent the vertical geological sequence.
Assay results indicated the material contains about 20% magnesium, alongside 7-10% iron, 2,000 to >10,000 ppm chromium, 700-2,500 ppm nickel and 130-150 ppm cobalt.
The testwork has also generated baseline metal recovery and process performance data to support further development, including testing of a Reagent Management System (RMS). Recent RMS testwork on similar material demonstrated a magnesium concentration factor of at least 2 times, which could reduce downstream processing requirements.
Panther said further metallurgical testing will be required, including mass balance verification, reproducibility studies and techno-economic evaluation, before any move towards pilot-scale testing or commercial process design.
Panther Metals Chief Executive Officer Darren Hazelwood said: "When we commissioned the Phase 1 testwork, our objective was to answer one fundamental question: 'Can we recover the magnesium from Dotted Lake?'
The answer is 'Yes!'. We now know that we can.
Achieving a 38 wt.% magnesium recovery at this first stage of work is an extremely exciting result for Panther. We started with a geological opportunity; we now have the initial technical validation and the experimental baseline, that the magnesium can be recovered.”
View from Vox
The 38% magnesium recovery result provides an encouraging early indication that Dotted Lake's serpentinite could support an alternative magnesium extraction route. Further testing will be important, but the potential for magnesium recovery alongside other critical minerals adds another dimension to Panther's exploration story in Ontario.