Canada-listed explorer Gemdale Gold said on November 5 it had obtained metallurgical test results for its Pontio project in Finland, where conventional cyanide leaching recovered 91% of gold from a composite sample. United Kingdom-based SLR Consulting conducted the testing on material drawn from Gemdale Gold’s earlier 2026 drilling programme. The test recovered the gold in about eight hours, with cyanide consumption of 0.6 kilograms per tonne.
The leaching result provides preliminary evidence that Pontio mineralisation may be treated without a complex refractory processing route. The results reduce one area of technical uncertainty ahead of the project’s resource estimate, but do not establish reserves or project profitability. Gemdale still needs to demonstrate the deposit’s scale, verify recoveries across representative ore types and quantify capital and operating costs.
Flotation offers a potential copper product
Alternative open-circuit rougher flotation tests recovered up to 87.5% of copper and 70.5% of gold into a sulphide concentrate. The results came from open-circuit tests and should not be treated as final plant recoveries. Later stages of a commercial circuit can reduce the proportion of metal reporting to a saleable concentrate.
The tested feed material graded approximately 0.70 grams per tonne gold and 0.071% copper. The best preliminary cleaning result produced a concentrate grading 6.5% copper and 47.5 grams per tonne gold, suggesting a combined gold-copper product might be technically possible.
Processing route remains undecided
Direct leaching would focus on gold recovery, while flotation might add copper revenue but would require concentrate marketing, transport and smelter terms. Gemdale Gold has not selected a final processing flowsheet or established which option has the economic advantage.
Further work will include locked-cycle flotation testing, additional leaching of flotation tailings and studies of pyrrhotite separation. The laboratory measured a Bond work index of 18.16 kilowatt-hours per tonne, an indicator that grinding energy is likely to be relevant to future processing economics. Gemdale Gold is targeting an initial mineral resource estimate for Pontio in early 2027.
