Yandal Resources Ltd (ASX:YRL) will this week begin an aircore drill program comprising about 110 holes for 8,000 metres across the company’s Mt McClure, Barwidgee and Ironstone Well projects in WA.
The program is expected to take around three weeks to complete and comes after ongoing target generation work – including geological and geophysical reviews - identified several high-priority targets for testing.
Each target gives Yandal a strong opportunity to discover significant new gold mineralisation at prospects close to existing mines and haulage infrastructure.
Yandal’s projects are all within the highly mineralised Yandal Belt in Western Australia.
The company has earmarked prospects returning positive results for detailed follow-up drill testing in the coming quarters.
Next phase of drilling
“We are looking forward to getting this next phase of drilling underway across some very encouraging targets within the highly mineralised Yandal Belt,” Yandal Resources’ managing director Tim Kennedy said.
“Yandal is fortunate to have extensive tenement holdings strategically located near operating mines and development projects. Despite a long history of exploration, it is clear to our team that there are many areas around these existing operations that have yet to be effectively evaluated.
“We have an ongoing target generation program that has highlighted several priority targets for immediate drill testing.
"We will also review results from RC drilling completed at Mt McClure in December and the outcome of this work will help refine targets for the next round of RC drilling with the aim of further delineating prospects and adding to the existing resource base.
“Interestingly, at Mt McClure, we have identified a previously untested historical soil geochemical anomaly proximal to a granite that is a focus of mineralisation immediately to the east of our tenure.
"One of the first rules of exploration is to explain geochemical anomalies as they can be direct indicators of mineralisation, so we’re very keen to put some holes into this one.
“Further to the north at Ironstone Well and Barwidgee, targets include Marianas along the Barwidgee Shear where limited effective drilling in the 1990s intersected up to 7 metres at 4.3 g/t gold.
"Our exploration is ongoing and we are eager to get our boots on the ground and start drilling these initial targets.”
Target breakdown
Mt McClure
The Mt McClure Project is 15 kilometres southwest of Northern Star Resources’ historic Bronzewing gold mine and 10 kilometres from its Orelia gold mine in the southern Yandal Belt.
The greater Mt McClure gold camp covers a strike length of around 30 kilometres and includes Northern Star’s Orelia mine (+1 million ounces), which has a total gold endowment of +1.8 million ounces of gold.
It also covers a total strike length of 17 kilometres of prospective stratigraphy and includes several historical open cut pits from which a total of approximately 100,000 ounces of gold was mined to maximum depths of between 60 to 100 metres mostly in the early 1990s at a time when the gold price was much lower than at present.
Location map of Mt McClure, showing key prospects, geological structures and planned drill target areas over RTP2VD aeromagnetics.
In the September 2022 quarter, Yandal announced an initial mineral resource estimate totalling 2.25 million tonnes at 1.9 g/t for 136,000 ounces beneath the Success, Parmelia and Challenger historic open pits and one satellite deposit.
The majority of targets in the current program are in the poorly explored hanging wall, east of the main line of mineralisation, on or adjacent to the north-east trending faults, with preference given to locations proximal to cross-cutting (conjugate) faults and/or areas exhibiting demagnetisation, potentially representing alteration associated with mineralisation.
One target MMCAC4 comprises an area of previously undrilled soil geochemical anomalism extending over 300 x 300 metres (peak value 176 ppb gold against a background of less than 10ppb gold) on the northern margin of a granitic intrusive coincident with a structural intersection. This same intrusive is host to significant mineralisation at the “'nomaly 45' prospect, immediately to the east of Yandal’s tenure.
Barwidgee and Ironstone Well
The 100%-owned Ironstone Well and adjacent Barwidgee Projects cover more than 400 square kilometres of contiguous, highly prospective and under-explored tenure between the Jundee and Bronzewing mines in the northern Yandal Belt.
Yandal has an established resource of 268,000 ounces of gold at Flushing Meadows within the Ironstone Well tenure. The company believes there is strong potential to make new discoveries and expand this resource base within the extensive tenure holding.
The project area has numerous prospects including several with high-grade gold potential such as Sims Find which are the subject of ongoing exploration. Outside these prospects, there are extensive areas along known structures and along poorly defined interpreted structures that have been subject to little if any exploration.
Yandal is completing a project-wide target generation exercise using an external consultant, specifically designed to identify targets with high potential for discovery along these poorly understood structures.
In this initial round of drilling around 50 aircore holes for 4,000 metres of drilling will test three target areas.
Drilling along strike from known high-grade mineralisation on well-defined structures as well as a first-pass assessment of interpreted structures, will test for mineralisation and provide geological and geochemical information to be used in ongoing targeting.
Targets include the Marianas Prospect about 4 kilometres northwest along strike of Corboys, along the Barwidgee Shear proximal to the granite-greenstone contact.
Reconnaissance style mostly shallow RAB drilling in the late 1990s intersected up to 7 metres at 4.3 g/t including 1-metre at 24.5 g/t from 20 metres (Hole ERAB67).
Mineralisation was thought to be associated with a granodiorite quartz porphyry which has intruded the main granitic body marginal to the granite-greenstone contact. The prospect area was subject to only limited follow-up and remains largely unexplored.
What’s to come
It will be a busy March quarter for Yandal as it looks to achieve its priority goals. These include:
- Assess the results of the RC drill completed at Mt McClure in December 2022 and plan follow-up drilling.
- Complete 3D modelling of historic and recent drilling data at Mt McClure to establish controls on potential higher-grade plunging shoots for follow-up drill testing.
- Aircore drill testing of new structural and geochemical targets at Mt McClure, Ironstone Well and Barwidgee.
- Integration of new high-resolution aeromagnetic survey data and RC follow-up along the high-grade Sims Find trend and other advanced prospects at Barwidgee.
- Complete a targeting study at Ironstone Well/Barwidgee assessing some of the lesser explored areas along potential 2nd and 3rd-order structures in preparation for future drill testing.
- Review of key prospects at Gordon’s and drill hole planning.