With production plans at the Tomingley Gold Operations (TGO) in Central West New South Wales in place to 2032, Alkane Resources Ltd (ASX:ALK, OTC:ALKEF) is confident ongoing regional exploration will add to the resource inventory and extend mine life.
There is considerable scope for this with the Tomingley Gold Project (TGP) covering about 440 square kilometres and stretching 60 kilometres north-south along the Newell Highway from Tomingley in the north, through Peak Hill and almost to Parkes in the south.
TGP contains Alkane’s TGO, an open pit and underground operation with a 1 million tonnes per annum processing facility that is on track to expand to an annual production rate of 1.75 million tonnes by the end of FY26.
Previous regional success
Over the past several years Alkane has conducted extensive regional exploration that led to the definition of resources at the Roswell and San Antonio deposits, separate to the established resources at Tomingley.
The company has completed a 2.7-kilometre-long drive to Roswell from the Wyoming One open cut and Roswell and San Antonio now form part of TGO, with processing of ore from underground at Roswell beginning in April 2024.
The focus for the exploration team has turned to other targets within the TGP, both near-mine and further out from Tomingley.
Recent exploration
Regional exploration for the TGP over the previous 12 months comprised airborne geophysical surveys, aircore drilling focusing on the eastern margin of the Mingelo Volcanics belt and at the Allendale gold-copper porphyry prospects, and deeper reverse circulation (RC) and diamond drilling focusing on Plains and El Paso prospects within 7 kilometres of the processing facility.
Alkane managing director Nic Earner said: “We continue to explore at Tomingley both within our approved mining areas and regionally.
“With current plans already extending to 2032, we are seeking to add further mine life, scale and grade to Tomingley.
“It is pleasing to see the various exploration targets around Tomingley yielding results and we look forward to continuing to add to our resource base.”
Promising assays
As part of the recent exploration drilling, assay results were received from 121 aircore drill holes for 11,621 metres; 5 RC holes for 1,550 metres; and 7 diamond core drill holes for 2,372 metres of core (excluding mud rotary pre-collars).
Drilling at El Paso prospect and south of the San Antonio deposit (406,000 ounces resource) has improved understanding of the local geology, leading to the delineation of new targets for testing.
New prospective andesite targets were identified east and south of San Antonio within the mining lease and significant mineralisation associated with a prospective dacite unit was intersected at El Paso.
Results include:
- 12 metres grading 1.50 g/t gold from 297 metres, including 4 metres grading 2.55 g/t from 301 metres;
- 3 metres grading 1.49 g/t from 130 metres and 12 metres grading 1.07 g/t from 216 metres, including 1 metre grading 4.3 g/t from 216 metres also 1 metre grading 3.98 g/t from 221 metres.
Four RC drill holes tested along-strike and down-dip to the known mineralisation at the Plains prospect hosted within an extensive basaltic andesite. Results indicate the gold structures are continuous and further work will be scheduled:
- 9 metres grading 0.76 g/t gold from 165 metres and 4 metres grading 0.89 g/t from 184 metres; and
- 6 metres grading 1.31 g/t from 312 metres.
Assay results have been received from 85 holes drilled along traverses spaced 500 metres to 1,000 metres apart. The most significant zone is from three adjacent holes about 1-kilometre southeast of the El Paso prospect:
- 3 metres grading 0.43 g/t gold from 96 metres and 2 metres grading 0.68 g/t from 108 metres;
- 3 metres grading 0.70 g/t from 78 metres; and
- 3 metres grading 0.31 g/t from 75 metres.
Survey work
An airborne gravity gradiometry survey was also completed over the northern half of the TGP. Interpretation of the data has improved delineation of the Mingelo Volcanics belt with new structures identified and the discovery of a possible new volcanic belt buried to the east of Peak Hill.
Alkane is also encouraged by results of an honours research project on the epithermal gold (±copper) deposits at Peak Hill was completed at the end of 2023. This project sought to identify a link between the known epithermal gold deposits and a potential porphyry copper-gold deposit at depth.
It found that the Peak Hill epithermal system is deeply eroded and that an underlying porphyry source could be in proximity to the Peak Hill gold deposits.
Reprocessed 2D seismic data has identified a high-priority drill target characterised as a flexure in a significant structure inferred to be a major gold conduit 2 kilometres southwest of TGO and only 800 metres below surface.
Drilling and exploration data compiled from these activities has enabled Alkane to prioritise a number of targets with follow-up scheduled for this quarter.