King River Resources has completed a first-pass exploration campaign ahead of schedule at the historic Mindoolah gold project near Cue in WA’s Murchison region ahead of schedule, drilling 1583 metres across 169 reverse circulation (RC) holes on old waste dumps and stockpiles.
The decision to drill the dumps followed King River’s May review of Mindoolah, in which a drone LiDAR survey and volumetric analysis identified a major mismatch between official historical production records and the amount of material physically excavated from the old pits.
The review estimated about 746,000 tonnes of surface stockpiles and waste dumps remained on site – almost 340,000 tonnes more than reported - setting the platform for the now-completed drilling campaign.
The company says the drilling covered the main historical surface dumps and stockpiles at its Excelsior, Cundy and Mindoolah Main Reef mine workings. The program was designed to pin down gold distribution, test grade variability and establish baseline grades across previously excavated material left behind by earlier miners.
The first sample batches are now on their way to the laboratory, with initial assays expected from late July. King River says the early completion of the stockpile and dump work has allowed its lightweight mobile RC rig to move straight into the next phase of the campaign.
Part two of the program is aimed at drilling beneath old workings where exploration by previous owners may have missed the true orientation of mineralised structures. It will also test shallow extensions and reconnaissance targets next to and beneath 1980’s-era open-cut pit floors and old underground workings, including shafts dating back to the early 1900’s.
Priority areas include the historic Excelsior, Cundy, Bertram’s and Mindoolah Main Reef mining areas. King River hopes the work will prove up previous drillhole logging, confirm gold-lode continuity and build its understanding of the structural corridors that control and host primary gold mineralisation.
In its latest field update, the company says ongoing mapping has added more spice to the story by sniffing out more structural and lithological targets across the old pit areas. At Cundy, the team has mapped a prominent anticline, with folded banded iron formation (BIF), chert horizons and quartz-vein repetitions, providing insights into the target geometry.
King River has also completed raw data collection from its low-altitude aeromagnetic geophysical survey, which was used to map concealed structures and lithological contacts across 9.5 square kilometres of the project.
King River Resources managing director Graham Gadsby said: “The speed and precision with which our exploration team has advanced field activities at the Mindoolah Mining Centre is an excellent achievement, putting our Phase 1 campaign well ahead of schedule. By rapidly concluding the high-density grid drilling phase across the historical waste dumps and stockpiles, completing 1,583 metres across 169 holes, we have successfully dispatched our first physical batches of drill samples to the laboratory weeks earlier than initially projected.”
The company expects the fully processed data to be delivered by the contractor, Magtech Surveys, next week. The information will then be integrated with other analytical, mapping and geological datasets to work up the next round of drilling targets.
With samples already on their way to the laboratory and the rig now chasing deeper and potentially harder rock targets below the old workings, King River has quickly shifted gears at Mindoolah. What began as a historical assessment of old dumps and mined material is now rolling into a more active test of the goldfield’s future potential.
The next few weeks should show whether the old goldfield still has a few new tricks left up its sleeve. If the assays and geophysics start to line up with the company’s fresh structural thinking, Mindoolah could quickly become more than a clean-up job around old workings.
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By Doug Bright
