Great Boulder Resources (ASX:GBR) has intersected gold grading at up to 54.33 grams per tonne in extensional drilling at its Mulga Bill prospect, with the new results to be incorporated into a resource update.
Extensional drilling north of the 568,000 ounce resource returned hits of 10m @ 17.22g/t gold from 112m, including 3m @ 54.33g/t from 119m; and 2m @ 15.82g/t from 170m, including 1m @ 30.70g/t from 170m.
The latest results are expected to extend the Mulga Bill deposit northwards by 300m.
Managing Director Andrew Paterson says these results are from the final 2024 reverse circulation program aimed at adding definition to previous “high-grade” intersections at the northern end of Mulga Bill.
“As a result it’s fantastic to see these really high-grade zones focused around the lithological contact and hosted within west-dipping quartz veins, as predicted by our structural model,” he says.
“The team is now incorporating this data into mineralisation wireframes in preparation for an updated resource estimate.”
Gold has also been intersected north of the second cross-cutting dyke at Mulga Bill, with mineralisation open into Mulga Bill North.
Great Boulder says this bodes well for further exploration along strike.
Eleven RC holes were drilled at Mulga Bill for a total of 2,075m, with seven drilled outside the resource north of the cross-cutting Proterozoic dyke, which previously marked the northern extremity of the deposit.
Previous drilling in this area identified “high-grade” gold mineralisation in the same style and orientation as Mulga Bill, which is part of the Side Well Gold Project in Western Australia.
The prospect forms the southern half of a mineralised system which has been defined by drilling over about 2.5km of strike.
The extension represents a relatively small portion of the untested or underexplored potential including Mulga Bill North, according to Great Boulder.
The junior explorer, which has a market capitalisation of $35.7 million, also entered a trading halt this morning ahead of the release of metallurgical testwork results.
“We are also looking forward to receiving the results of metallurgical test work completed on Mulga Bill samples late last year,” Paterson says.
“It’s been a very busy start to the year for Great Boulder, and we anticipate an exciting year ahead as we progress Side Well towards the development phase.”
The testwork investigated gravity recoveries and cyanide leach extraction on samples with different mineralisation styles and oxidation states, from weathered to fresh rock.
Results are also expected shortly from aircore drilling at the Whiteheads project near Kalgoorlie and aircore drilling and a gravity survey at Side Well South.
Drilling at Side Well is expected to restart in late January after Great Boulder reassesses all exploration targets and opportunities within its Meekatharra projects.
Great Boulder is focused on gold and base metals exploration in Western Australia. The company’s primary focus is Mulga Bill, but it is also exploring for gold at the Whiteheads Project near Kalgoorlie and for zinc and lead at the Wellington Project in the Earaheedy Basin.
Write to Angela East at Mining.com.au
Images: Great Boulder Resources
