Drilling at Ora Banda Mining’s (ASX: OBM) Callion gold deposit in WA’s north-eastern goldfields has returned further high-grade assays for owner.
Drilling of 53 reverse circulation holes for a total 6,938m and 17 diamond tails for 1,948m focused on extending and upgrading the current open pit at the deposit and delineating a maiden underground resource.
Ora Banda aimed to build on open pit assays from an earlier campaign of 10m at 8 grams per tonne gold from 76m and 5m at 3.3g/t gold from 73m, and underground results of 4.8m at 34.4g/t gold from 232m, including 0.3m at 498.2g/t gold.
Best open pit results from this morning’s announcement were 2m at 6.95g/t gold from 109m; and 7m at 1.7g/t gold from 102m, including 3m at 3.34g/t gold.
Meanwhile, underground results were 8m at 20.2g/t gold from 118m; 8m at 16.4g/t gold from 139m; and 10m at 3.5g/t gold from 158m.
An underground assay of 8m at 16.4g/t gold from 139m held particular significance for Ora Banda, as it intersected the along-strike continuation of a high-grade shoot associated with the historical main underground mining area.
The overall shoot plunge continuation at depth remains a focus for future exploration works.
Managing director David Quinlivan was pleased with the results of the ongoing drilling campaign.
“Receiving these results now allows us to move forward with the progression of the Callion mineral resource update,” he said.
“Pleasingly, the high-grade nature of this deposit continues to shine through.”
Located 13km south-west of the Davyhurst Mill within the north-eastern goldfields region, the Callion deposit has been mined underground by various operators since the early 1900s.
More substantial development was undertaken by Western Mining Corporation during the 1930s and 1950s.
Additional underground activity and open pit mining works were carried out by the Callion joint venture in the 1980s, prior to a second round of open pit development by Croesus Mining in 2004.
The existing Callion open pit is approximately 650m long and 40m deep, with the underground workings extending off the southern end of the pit to a vertical depth of 220m below surface.
Total recorded historical production for the open pit is 13,000 tonnes at 4.1g/t gold for 17,600oz, with the underground mine producing 146,000t at 15.8g/t gold for 74,000oz, for total production of 280,000t at 10.2g/t gold for 91,650oz of contained gold.
Ora Banda’s conceptual development plan for Callion includes an open pit cut back to re-establish underground access, rehabilitation of the historical underground workings to extract a number of high-grade zones which remain within the upper sections of the mine, and the development and extraction of new high-grade areas below the mine.