Galena Mining Ltd (ASX:G1A) has received strong lead, silver and copper results from the first two exploration holes drilled underground at the Abra Base Metals Mine in Western Australia, which hit the northern extension of mineralisation.
The two diamond holes drilled to the north of the Abra Fault confirmed the presence of Abra-style Apron and Core mineralisation, returning multiple lead and silver intercepts with copper as well.
This provides encouragement for Galena as the existing Abra resource estimate has been constrained to the north by the Abra Fault and does not include the new mineralisation.
Strong results
Best results from the drilling in quarter four of 2022 are:
- 4.8 metres at 3.1% lead and 6.7 g/t silver from 276.88 metres;
- 3.7 metres at 4.0% lead and 7.2 g/t silver from 286.48 metres;
- 2.4 metres at 5.1% lead and 9.6 g/t silver from 314.42 metres;
- 6.9 metres at 4.9% lead and 7.5 g/t silver from 352.73 metres, including 2.1 metres at 10.6% lead and 22 g/t silver from 352.73 metres and 1-metre at 1.9% copper from 338.66 metres.
“Reward for hard work”
Managing director Tony James said, “This drilling confirmed our belief that Apron-style mineralisation is north of the Abra fault and offset some 70–100 metres below the top of the Abra mineralisation.
“It's very pleasing to see these results in the very first underground exploration holes we have drilled and it's a great reward for the team’s hard work to get the mine to this stage.
“It’s also nice that our progress to date and confidence in the ore body has allowed us to start to do some exploration work on one of the many targets we have at Abra.”
The newly identified mineralisation is quite expansive, covering about 100 metres by 300 metres and is open to the north, east and west directions.
Drilling also confirms the approximate displacement on the north side of the Abra fault is about 70-100 metres lower so the newly encountered mineralised zone remains within the mining reach of the existing mine plan.
Dual-purpose holes
These diamond holes were drilled as dual-purpose holes for exploration of a previously identified target and geotechnical evaluation for underground development planning.
The two holes were drilled in October 2022, adjacent to a historical intercept drilled by Abra Mining Limited in 2007.
Including the historical hole, the three holes are spread over an area of 300 metres east-west and 100 metres north-south.
They are about 200 metres from the current Abra Deposit and 100 metres from the proposed Abra decline infrastructure.
Also, 700 metres north of the Abra fault, an additional mineralisation target known as the 'Ale' prospect, was identified when drill hole AB42 was extended in 2019 intercepting 4.3 metres at 6.1% lead and 8.4 g/t silver from 563.2 metres downhole depth, with a single sample reporting in excess of 20% lead mineralisation.
The 2021 Abra mineral resource classification boundaries over the Apron Domain lead mineralisation lodes (red), and the significant lead and silver mineralisation intercepts for historical drill holes AB41, AB42, and the new underground drill holes 22AUD0159 and 0160, with the addition of the current known and unknown mineralisation potential north of the Abra Fault and current Abra Deposit resource.
Updating mining models
Before the two exploration holes, underground drilling has been focused on grade control and resource conversion to support Abra mine production planning for 2023.
As a result of the 122 underground drill holes completed in 2022, Galena is updating the geology and mining models in the areas where this drilling occurred.
Results associated with the drilling completed to date is considered positive in relation to the previous work.
Abra mine achieved its first concentrate production on January 12, 2023, with more than 1,000 tonnes of saleable concentrate produced during plant commissioning to date.
The project remains on target to achieve first concentrate shipment in this quarter.
Further drilling
As mining and drilling progress at Abra in 2023 further exploration targets will be planned for drilling.
Planning is underway to test some of the copper targets previously identified as soon as the underground development reaches suitable locations to optimise the drilling of these targets.
These copper mineralisation targets sit within the base of the hydrothermal breccia.