Ora Banda Mining has nailed high-grade gold hits at its Davyhurst project in Western Australia’s historic Goldfields region from infill and extensional drilling at depths of 500 metres to 1000m below surface at its premier Riverina deposit.
An exploration drill program at the company’s emerging Waihi and Little Gem prospects also unearthed a suite of mineralised intersections.
Multiple hits exceeded 100 grams per tonne (g/t) gold at Riverina, with both Waihi and Little Gem returning several high-grade gold intervals grading more than 10g/t.
At Riverina, significant intervals consisted of a 1.7m hit at 76.4g/t that included 1m at 129.5g/t, a 4.3m stretch going 24.6g/t including a pumped-up 0.3m slice grading 229g/t and 4.7m running at 12.5g/t with a 0.5m section returning 108g/t. Other notable hits were 1m going 92.4g/t and 2m assaying 28.2g/t.
Recent drilling has confirmed Riverina contains a continuous strongly mineralised system extending to 1000 vertical metres, providing significant potential for future mine life extensions. The deposit’s stratigraphy comprises a 500m wide sequence of mafic-ultramafic and metasedimentary units, bounded by ultramafic to the west and a thick metasedimentary package of the eastern hanging wall.
The company says gold mineralisation across its Main Lode, Murchison, Reggie’s and Durham lodes is within 100m of the eastern metasedimentary contact. Its main lodes are hosted within a 25m wide shear corridor and exhibit excellent continuity at depth.
Management says a total of 20,548m of diamond drilling and 9468m of reverse circulation drilling has been completed since the company started a resource extension program last October. The deepest diamond hole reached a vertical depth of 1200m, intersecting the targeted mineralised corridor and validating Riverina’s depth potential.
Ora Banda Mining managing director Luke Creagh said: “These strong new drill results across three distinctly different areas are testament to the prospectivity of the Davyhurst gold project. We remain extremely active on the drilling front, with five surface rigs turning and five underground rigs active, which combined, are producing more than 850 metres of diamond core a day.”
Creagh said the Waihi results were significant as they promote the deposit’s potential to become the company’s third underground mine.
At Waihi, the first seven-hole program has been completed. It was designed to target high-grade shoots beneath the historical open pits.
One hole encountered a new mineralised zone in the footwall of the main mineralisation at 330m below surface, which had a stellar 8.7m interval grading 9.3g/t gold. The hit included 1.1m at 30.2g/t and a 0.4m slice going 90.6g/t.
The new find remains largely untested up and down plunge and presents a new zone for further drilling, which Ora Banda expects to schedule in the near term.
Additional promising gold assay results included 0.4m at 18g/t and a 1.5m section returning 18.6g/t.
The company is currently designing a significant follow-up drill program, which it plans to begin in the next financial year.
After an initial five-hole drill program at the Little Gem prospect that returned 22.7m at 5g/t and 10.9m grading 6.4g/t, management committed to a 16-hole broadly spaced phase two program to test the carbonate horizons across 4.7 kilometres and to a depth of 400m below surface.
The program spaced at 400m section lines will enable testing of the Little Gem-Sunraysia grounds’ greenfield potential and determine the system’s structural and lithological architecture.
Notably, carbonate units have been intersected along the entire length of drilling conducted to-date, confirming a continuous 5km strike between Little Gem and Sunraysia. It remains open to the north and south, with a prospective fault zone at the southern end of Sunraysia only tested by one historic rotary air-blast hole, which returned a significant 4m hit at 11.5g/t gold.
The carbonate units vary in thickness from 0.2m to 0.6m. Current assays show all carbonate units intersected by drilling are mineralised with variable gold grades.
The company has received assays from three holes, and a further nine holes are awaiting results. Four more holes are currently being drilled.
A high success rate from drilling is proving the company’s working geological model to be sound. Further infill drilling is planned at the prospect.
The mid-tier goldie recently revealed an impressive 35 per cent lift in annual gold output at Davyhurst to 95,000 ounces, albeit slightly short of its previous guidance of 100,000 ounces.
Davyhurst now has two operating underground mines. The Riverina deposit is making a substantial contribution to its output by half-filling its 1.3 million-tonne processing plant.
Recently, management’s focus has moved to ratcheting up the company’s newer Sand King deposit to fill the mill with high-grade feed. The move will provide Ora Banda with another significant step-up in its quest for increased production and cash flow.
The continued high-grade gold assays returned from the company’s drilling efforts point to Ora Banda’s decision to head underground as potentially a sustainable game-changing move.
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By Craig Nolan
