Larvotto Resources says it has turned up abundant coarse grains of visible gold in its first diamond-core drilling at the Hillside gold-antimony project in New South Wales, with assays expected next month.
The company says its 2036m of drilling at the historic Bakers Creek Mine at its 100 per cent-owned Hillside project chased extensions of previously-reported high-grade gold-antimony mineralisation of up to 525 grams per tonne gold from its Little Reef lode.
That result was reported by previous owners Red River Resources from its 2022 drilling that included 0.45m at an eyebrow-raising 257g/t gold, 0.4m going 96.8g/t and 0.6m running 108 g/t. The latter intersection accompanied a 0.4m intercept higher in the same hole at the stunning 525g/t result.
Other broader intercepts reported by Red River included 9.5m at 4.3g/t gold and 0.8 per cent antimony from 70m, in addition to 20.3m at 4.1g/t gold and 0.9 per cent antimony from 51m. Red River also reported abundant visible coarse gold, with more than 50 pieces ranging from “sub-millimetre up to two square millimetres in size”.
Larvotto says it has completed its first round of diamond drilling at Baker’s Creek, which it kicked off in February, putting in a total of seven holes. It says drilling intersected several zones of visible gold in quartz-carbonate breccias and quartz-carbonate veins associated with wider carbonate-altered breccias accompanied by visible antimony sulphide (stibnite) mineralisation.
While at this stage the company says it could not specifically identify the Little Reef lode in the core, it noted significant visible gold in breccia and stringer zones, which it believes could represent parallel lode zones or zones in a possible “pinch-and-swell” style mineralisation zone between the main workings and the broad zones seen in the core.
Larvotto Resources managing director Ron Heeks said: “The diamond drilling program at Bakers Creek was always a priority, aimed at building on the significant high-grade intercepts from drilling undertaken in 2022. Identifying visible gold in the deeper part of the Hillgrove system helps confirm that it may be geologically similar to the high-grade gold and antimony systems identified at the Costerfield Mine operated by Mandalay and the high-grade gold mineralisation identified by Southern Cross Gold in Central Victoria.”
The company says five successful holes ran to downhole depths ranging from a minimum of 279.3m to a maximum of 529.9m. Samples cut from three holes have been sent for analysis, while core from the two remaining holes is still being cut.
Before slipping into administration, due mostly to difficulties with its Queensland operations, Red River had planned to refresh the Hillgrove reserves base and increase resources through exploration of both new and existing targets. It spent about $20 million on exploration and successfully increased resources and generated several more high-grade new targets adjacent to existing resources, which Larvotto says it now plans to follow-up.
Red River left behind a valuable legacy in an overall 1.4-million-ounce gold resource for the project at an estimated 6.1g/t gold equivalent. Bakers Creek’s past production, mostly between about 1880 and 1916, is estimated at about 304,000 ounces of gold from 176,000 tonnes of ore for an average grade of more than 50g/t gold – making it the most productive gold mining area in the Hillgrove mineral field.
Additionally, Red River left behind a database including old records showing the mine tailings storage facility (TSF) contains about 1.4 million tonnes of tails. Tailings are the fine-milled waste discharge from the operation that often become the subject of renewed economic interest as they can carry potentially economic grades of the commodities originally sought in higher commodity price cycles.
At Hillgrove, records show a fair bit of gold and tungsten also slipped past the processing and ended up in the TSF. Current estimates indicate the TSF contains a grade of about 1.34g/t gold, while tungsten grade is currently unknown. None of the mineralisation contained in the tailings is included in Larvotto’s current mineral resource.
The company recently finished a metallurgical auger drill program to determine just how much gold, tungsten and antimony was left behind in tailings from mining campaigns dating back to the early 1980s at Hillgrove and to assess the viability of reprocessing the tailings for one or more of the three key commodities – gold, antimony and tungsten.
If viable, direct tails reprocessing – or perhaps as gradual feed augmentation to a future hard-rock gold processing operation, subject to metallurgical studies – could be a cost-effective early lead-in to the main game at Hillgrove.
The Hillgrove tenure encloses a total of 254 square kilometres made up of four exploration licences and importantly, 48 granted mining leases. More than 204 individual mineral occurrences have been identified to date in the greater region, with their mineralisation often developed as strike-extensive veins up to 20km long, with potentially deep, steeply-dipping fissures.
The current mineral resource puts Hillgrove in the world's top 10 antimony deposits. In addition to containing high-grade gold and significant tungsten, it is Australia’s biggest antimony deposit. Both antimony and tungsten are designated as strategically-critical commodities by many countries including the United States, China and Australia and the European Union.
Larvotto says it will soon to kick off a drill program at Clarkes Gully aimed at near-surface gold targets above deeper mineralisation that is already included in the current mineral resource and which might be amenable for open cut mining prior to underground mining of deeper zones. Management says it is working to deliver an initial ore reserve estimate at Hillgrove in the near term from its significant mineral resources.
It sees that as a priority at a time of record Australian gold prices and a near-record antimony price. The company says its current resource objective is to merge all results from Bakers Creek and Clarkes Gully and incorporate them into an updated mineral resource estimate.
Management is also reviewing ore reserves, which could support a preliminary feasibility study that is already in train, in addition to relevant metallurgical testwork, mining studies and plant rehabilitation and upgrade reviews.
With coarse visible gold in the core, it is not hard to imagine someone in Larvotto wishing they could be a fly on the wall of the assay laboratory as it works its way through the company’s samples.
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By Doug Bright
