Parys Mountain - Positive Preliminary Results from Metallurgical Testwork

Anglesey Mining plc (AIM:AYM), the UK minerals development company, is pleased to report that it has received preliminary results from the metallurgical testwork on the White Rock and Engine Zones at the Company’s Parys Mountain Cu-Zn-Pb-Ag-Au project, located on the Isle of Anglesey.

In June, the Company dispatched a 340kg sample to Grinding Solutions Limited (GSL) comprising a blend of material from both the White Rock and Engine Zones with a combined head-grade of 0.42% Cu, 3.60% Zn, 3.08% Pb, 49g/t Ag and 0.7g/t Au (10.8% ZnEq). The blend was 3.3 (White Rock) to 1.0 (Engine Zone), similar to the contribution that is expected to be delivered from the mine in the early years of production, prior to the Northern Copper Zone commencing.

Highlights

Two pre-concentration methods were conducted – Dense Media Separation (DMS) undertaken by Pesco and X-Ray Transmission sorting (XRT) completed by TOMRA. One element of the testwork was to determine the optimal process to take forward into the Pre-Feasibility Study.

Both methods demonstrated that a successful pre-concentration stage would be applicable with the overall base metals only head-grade increasing from 7.5% ZnEq to 11.4% ZnEq from the DMS (+52%) and 11.7% ZnEq from the XRT (+55%) – results will be updated once the gold and silver numbers are finalised – the precious metals are expected to add 3-4% to the ZnEq grade. The preliminary results are tabulated below:

Preliminary results from the locked-cycle flotation testwork demonstrated higher recoveries than those achieved in historical testing. These results are based on calibrated pXRF readings with the full wet chemistry expected over the coming 2-3 weeks. The results are tabulated below:

Testwork with regards to net acid generation, settling rates and contact leaching on the tailings is ongoing with results expected over the next 2-3 weeks. In addition, GLS will also be completing a diagnostic leach test on the final zinc tailings to ensure optimal recovery of gold.

Jo Battershill, Chief Executive of Anglesey Mining, commented: “We are very pleased by the preliminary results from the metallurgical testwork on the White Rock and Engine Zones, which have demonstrated that the assumptions used in the 2021 PEA are potentially on the conservative side. The results show that the overall metal recoveries appear to be better than expected, particularly for both copper and gold. It is also very positive to confirm that the Parys Mountain deposit is amenable to both DMS and XRT pre-concentration methods with the potential feed grade increased by over 50%.”

“Successful pre-concentration has many benefits ranging from increased feed grade into the processing plant, lower volumes of tailings for disposal and the potential to build smaller, lower cost processing infrastructure. We will now look to investigate the relevant capital and operating costs for each option to determine which is the most optimal route to move forward with in the planned Pre-Feasibility Study.”