In this edition of Bulls N’ Bears Big Hits we examine some notable drill intercepts revealed on the ASX last week, including Australian Gold and Copper’s Achilles discovery at its South Cobar gold-silver-copper project near Cobar in NSW. We also take a close look at other interesting drill hits from last week as reported by Laramide Resources’ from its Westmoreland uranium project in Queensland and PolarX from its Caribou Dome project in Alaska, USA. So, let’s dive in.
Achilles discovery, South Cobar gold-silver-copper project
Cobar area, NSW.
Australian Gold and Copper (AGC) hit pay dirt in its first diamond drill program at the company’s high-grade Achilles gold-copper discovery in the Cobar Basin in central NSW. The company scored significant results from the first two holes in its recently completed 10-hole, 2756m drilling program.
The latest numbers follow a recent string of reverse circulation (RC) drill hits in the preceding drilling which probed the shallower parts of the same target areas.
The highest grade diamond intercept was cored from a hole in the centre of the emerging deposit, yielding 9.1m at 3.0g/t gold, 698g/t silver, 1.2 per cent copper and 19.4 per cent lead plus zinc (“Pb+Zn”) from 126.5m.
That intercept includes 2.5m at 6.7g/t gold, a whopping 1,625g/t silver, 0.9 per cent copper and 18.5 per cent lead plus zinc from 126.5m.
The second diamond hole was drilled in the northern part of the deposit and recorded a longer run than the headline hole, with 19m at 0.3g/t gold, 73g/t silver, 0.5 per cent copper and 11.1 per cent lead plus zinc from 92.0m, including a high grade silver run of 4.5m at 227g/t silver and 3.4 per cent lead plus zinc from 93.0m.
The second hole also includes two high-grade base-metal zones of 1.6m at 1.9 per cent copper and 34 per cent lead plus zinc and 0.8g/t gold and 96g/t silver from 99.0m. Another 1.5m hit came in at 1.5 per cent copper and 39.3 per cent lead plus zinc from 108.1m.
AGC says the main north-striking Achilles Shear Zone (ASZ) controls the Achilles mineralisation where it contacts “various rock types” in the hanging wall.
AGC has been exploring the area for the past three years and in March last year, the company undertook a 26.4 line-kilometre induced polarisation (IP) geophysical survey at Achilles.
The program comprised three game-changing targeted surveys to better resolve the sulphide mineralisation in the South Cobar project.
From south to north, the three IP targets were the Hilltop, Achilles and Planet mineralised zones which are more-or-less equally-spaced at about 20 to 22km intervals along the Achilles Shear Zone. Interestingly, a fourth target lies about 22km north of Planet, but has not yet been tested by IP.
At Achilles, a northern ovoid IP anomaly sits 100m west of previous drilling under surface anomalism and hydrothermally-altered outcrop. Its top lies about 200m below surface, while its core is centred about 320m below surface and it appears to close off at about 600m depth.
A second big southern high-chargeability IP anomaly, about 500m wide, sits about 600m south of previous drilling and also beneath surface anomalism and altered outcrop.
Its top lies about 120m to 200m below surface and its core is centred about 700m below surface, although it disappears downwards off the modelled section, which means it could be even deeper.
The other two IP surveys at Hilltop and Planet also produced big clear anomalies up to 700m long which look similar to those from Achilles. All three centres sit along a 47km-long sinuous north-south strike of the prospective ASZ, which extends for about twice that distance, passing about 13km west of the town of Cargelligo.
In January, AGC’s maiden RC drilling of the ASZ at the Hilltop target confirmed high grade mineralisation is currently open in every direction and at depth.
Around April, the RC rig moved to Achilles to drill 10 holes for 1596m to test the southern IP anomaly, revisiting Achilles in July with 20 more holes for about 3000m of RC drilling, more IP surveying and the recent follow-up ten diamond hole program.
The diamond program only has the foregoing results reported from its first two holes, however core from the remaining eight holes was processed in the past week and results are imminent.
Some of the recent previous RC drilling was put in along the strike of the ASZ about 180m north and south of this week’s headline 9.1m intercept.
Results from previous RC drilling include two supportive RC intercepts within just 50m of each of the two recent diamond holes.
They include selected intercepts of 5m at 16.9g/t gold, 1667g/t silver and 15 per cent lead plus zinc ; 2m at 2g/t gold, 566g/t silver, 1.7 per cent copper and 23.2 per cent lead plus zinc; 4m at 2g/t gold and 257g/t silver; 16m at 31g/t silver and 18.5 per cent lead plus zinc, which includes 3m at 38.5 per cent Pb+Zn.
All of the latest RC and diamond results have come from exceptionally clear, wide, strong and deep IP anomalies.
IP surveys have also been key to recent high-profile discoveries such as Aurelia Metals’ nearby Federation deposit in the Cobar Basin and also at Carnaby Resources’ Greater Duchess iron oxide copper-gold project near Mt. Isa in Queensland.
Results from AGC’s next eight diamond holes will no doubt be keenly anticipated.
Westmoreland Uranium Project - Queensland, Australia
Toronto-based uranium explorer and developer Laramide Resources has concluded its drilling campaign at the Westmoreland uranium project in Queensland, Australia, producing a best result of 2.20m at 2675ppm uranium oxide and 1.51g/t gold from 63m, including 1.00m at 4092ppm U3O8 and 2g/t gold from 64m.
Other supportive intercepts include one 17m intercept running 469ppm U3O8 from 54m, including 3m at 1374ppm U3O8 from 60.00m.
A second hole produced 15m at 380ppm U3O8 from 61m, including 1m going 1987ppm U3O8 from 63m and also 16m at 573ppm U3O8 from 88m which includes 2m at 1713ppm U3O8 from 91m.
The company’s latest batch of assays includes the first results for its Huarabagoo and Junnagunna targets and show that uranium mineralisation is not only continuous along strike but also confirms a previously inferred link between the two deposits.
The Westmoreland uranium project tenements extend for about 30km east-west and 22km north-south next to the Queensland-NT border. The region was likely first prospected in the 1890s, after the discovery in 1887 of silver-lead deposits at Lawn Hill, 100km to the south.
The radioactive uranium-rich mineral, pitchblende, or uraninite (UO2), was mined in the Peters Creek Volcanics - which overlie the Westmoreland conglomerate - 20 to 30km west of Redtree.
The current mineral resource estimate for the indicated category in the company’s 2016 estimate includes the Redtree, Huarabagoo and Junnagunna deposits for a total indicated resource of 18.7 million tonnes at a grade 0.09 per cent U3O8 for 36 million pounds of U3O8.
The Huarabagoo deposit sits in the structural corridor between Redtree and Junnagunna.
The latest drilling results include 4 holes from 17 put in for 1827m at Huarabagoo and 12 holes (from 27) in the “Link Zone”, between Huarabagoo and Junnagunna, to test the extents of both uranium and gold associated with near-vertical intrusive dolerite dykes.
Laramide says the latest results appear to confirm that both uranium and gold lie on the margins of intrusive dolerite dykes and along fault extensions, with multiple zones intersecting a similarly-variable hematite-silicate-sericite altered sandstone.
Its 2012 drilling at Huarabagoo included one result of 34m at 1467ppm U3O8, including 10m at 3965ppm U3O8 - comprising new mineralisation east of the dyke - and another hole jagging 2m at 6.1g/t gold and also a juicy 4m going just shy of an ounce to the tonne gold.
The drilling undertaken in the Huarabagoo-Junnagunna structural corridor was also designed to test the continuity of mineralisation between the two deposits in a bid to increase the overall size of the resource.
First phase RC results at the structural corridor returned substantial intercepts, with one hole intersecting 17m at 469ppm U3O8 from 54m, including 3m going 1374ppm U3O8 from 60m and a second hole produced 2m at 260ppm U3O8 and 1.28g/t gold, including 1m at 415ppm U3O8 and 2.54g/t gold.
A third hole intercepted 15m at 380ppm U3O8 and 0.017g/t gold from 61m, including 1m running 1987ppm U3O8 from 63m, while a fourth hole bored 16m at 573ppm U3O8 from 88m, including 2m assaying 1713ppm U3O8 from 91m.
Most significantly, the drilling successfully intersected the dolerite dyke system under alluvial cover and its associated mineralisation across the 2km strike of the link zone, which will be critical for subsequent modelling of the link zone and to inform planning of future infill drilling.
Results from the Huarbagoo-Junnagunna link zone underscore the potential for substantial growth of the combined mineral resources. The shallow, broad mineralized zones, some of which express impressive higher grades, further validate the characteristics that Laramide sees across the whole Westmoreland system.
Core processing continues and assay results are expected to be announced throughout the end of this year and into early next year.
Once compiled, the latest dataset will lead to an updated mineral resource estimate for Westmoreland which will also include a maiden resource estimate for a satellite resource known as Long Pocket which is still on track for early 2025.
Caribou Dome project, Alaska, USA
PolarX has received further high-grade copper assays from thick zones of copper-bearing massive sulphide drill core intercepts it announced in early September, with assays for the final two holes drilled at Caribou Dome extending the high-grade mineralisation to depths below 300m from surface:
One of the final holes intercepted 20.5m at 1.7 per cent copper and 2.5g/t silver from 212.8m, which included 3.4m at 3.4 per cent copper and 4.6g/t silver and 1.3m assaying 5.9 pr cent copper and 10.4g/t silver.
The second hole of the pair provides added similar support by intercepting 11.6m going 1.8 per cent copper and 2.1g/t silver in hole from 256m, including 6.1m at 3.2 per cent copper and 3.5g/t silver including a sub-interval of 2.4m running 6.7 per cent copper and 7.4g/t silver from 263.7m.
All of PolarX’ mineralised intersections from its 2024 drilling program lie below a diamond hole it drilled in late 2021 which intersected 19.1m at an astounding 7.0 per cent copper and 11.2g/t silver and 9.8m going 6.8 per cent copper and 7.8g/t silver.
In the follow-up 2024 drilling, one hole intersected 8.7m at 4.3 per cent copper and 10.5g/t silver, including 3.4m at 7.6 per cent copper and 20.7g/t silver and also 1.5m at 5.7 per cent copper and 7g/t silver,
A second step-back hole intersected 15.5m going 7.4 per cent copper and 21.4g/t silver which included 8.1m at 11.4 per cent copper and 35.8g/t silver and 3.2m at 6.2 per cent copper and 7.5g/t silver.
New assay results also show a third hole intersected 20.5m at 1.7 per cent copper and 2.5g/t silver from 212.84m, including 3.4m going 3.4 per cent copper and 4.6g/t silver and 1.3m @ 5.9 per cent copper and 10.4g/t silver.
Additionally, new assay results from a fourth hole revealed shows an intercept of 11.6m at 1.8 per cent copper and 2.1g/t silver, including 6.1m assaying 3.2 per cent copper and 3.5g/t silver that included a sub-interval of 2.4m at 6.7 per cent copper and 7.4 g/t silver from 263.7m
PolarX’ Caribou Dome project sits about 250km north-east of Alaska’s biggest town of Anchorage.
Detailed structural logging of oriented diamond core has been successful in identifying down-dip offsets and has established where mineralisation continues beyond the structural offsets.
PolarX secured an 80 per cent interest in the Caribou Dome project in June. Only limited exploration had been undertaken since 1970, until PolarX secured exploration rights to explore and develop the project in early 2015.
The drilling has validated previous work and PolarX delivered a maiden resource in April 2017, followed by an update in mid-June last year to 7.2 million tonnes grading 3.1 per cent copper and 6.5g/t silver.
Copper mineralisation was discovered at Caribou Dome in 1963. It comprises nine deformed lenses of volcanic sediment-hosted fine-grained massive sulphides consisting mainly of chalcopyrite and pyrite.
Copper mineralisation has been defined along about 700m of strike and extends from surface to depths of over 300m, remaining open below the 300m depth of the modelled resource.
Multiple high-priority targets have been generated from surface geochemical soil sampling and IP surveys and all remain undrilled.
With more than 18km of the stratigraphic mineralised horizon being evident in the company’s project area, there is considerable potential to discover additional high-grade mineralisation and to continue to expand the resource base at the project.
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