Special Report: There’s never been a major, multi-million-ounce gold discovery on the western side of the Senegal-Mali Shear Zone. That’s about to change.

The eastern side of the prolific Senegal-Mali Shear Zone (SMSZ) is home to 45 million ounces of tier 1 gold production. The western side has barely anything.

Why? Because miners and explorers didn’t know how to pinpoint deposits under the western side’s thin layer of cover.

This cover is drenched during the annual wet season, making normal soil sampling techniques ineffective.

The east and west sides of the prolific Senegal Mali Shear Zone (SMSZ).

The first company to ‘crack the nut’ was ASX-listed Chesser Resources (ASX:CHZ), which replaced soil sampling with deeper auger drilling at its Diamba Sud project.

Auger drilling – an idea Chesser got from fellow ASX explorer Oklo Resources (ASX:OKU) — was a gamechanger for the entire western side of the SMSZ.

In 2019, Chesser discovered ‘Area A’ with impressive intercepts like 21m at 6.62 g/t gold.

But Chesser really caught the market’s attention in July this year with some extremely high-grade gold intercepts in five successive holes at the adjacent Area D, including 10m at 25.1 grams per tonne (g/t) and 48m at 6.7g/t.

Thick, shallow, and high grade – that’s the trifecta investors look for in drilling results.

Chesser now believes the adjacent Area D is quite possibly the continuation of Area A that has been ‘offset’ by a regional fault.

“The similarities with Barrick’s 5.5moz Gounkoto deposit around ~5km away on the eastern side of the SMSZ are very strong,” Chesser managing director Mike Brown says.

“I’m looking at a presentation from Randgold in 2011 – when they were hitting intercepts like 65m at 16.5g/t — and geologically this could easily be a cross section of our deposit.”

Diamba Sud could be a very large system. Chesser is currently knee-deep in a 20,000m drilling program to discover how big it actually is.

But Chesser isn’t the only one. Sparked into action by Chesser’s innovative auger technique, gold majors are now very active in the immediate neighbourhood.

A regional drilling frenzy

The high-grade gold discovery at Diamba Sud is surrounded by major gold producers Barrick and IAMGOLD.

On the eastern side of Diamba Sud is the Barrick Gold-IAMGOLD Bambadji joint venture: a project Barrick chief executive Mark Bristow has mentioned by name in both the Q3 and the Q4 earnings reports conference calls.

“Barrick had been sitting on it idle until we got our initial augur results,” Brown says.

“Then Barrick went through and re-did all their exploration work, and that’s when they made a discovery called ‘Gefa’ in the south.

“That’s their main target on Bambadji currently. They have been drilling that pretty hard for the last six months or so.

“They have also just started drilling immediately east of us near Area A.”

West of Diamba Sud is a joint venture called ‘Senala’ between TSX-listed miner IAMGOLD and prospect generator Oriole Resources.

In the second quarter of 2020, IAMGOLD kicked off a 10,000m drilling program at the Faré prospect in the north of the licence.

That’s 20km directly west of Diamba Sud.

Initial results from the programme are anticipated in the first quarter of 2021.

Old drilling at Fare – which was never followed up – pulled up incredible intercepts like 20m grading 31.13 g/t gold, including 10m grading 60.98 g/t.

“The historical results at Faré have already shown the potential for the development of a significant gold resource,” Oriole chief exec Tim Livesey says.

“As we have seen from recent drilling on other licences in the immediate surrounds of Senala, long intercepts with grades well in excess of 2 g/t Au can quickly build the types of volumes required for stand-alone mineable resources.”

So many ‘screaming anomalies’

There’s never been a major discovery on the western side of the shear zone, Chesser’s Mike Brown says.

But the amount of successful exploration activity in the area suggests this is about to change.

“We all have screaming anomalies which suggests that the geology is highly prospective,” Brown says.

“We aren’t trying to prove a model anymore; we have proven that the mineralisation is there, and that the geology is very similar to the eastern side of the SMSZ.”

For Chesser, there are multiple targets still to test at Diamba Sud.

“We are in a great position – we don’t need 5moz at Area D alone for this to work, because we have numerous other areas that could add to the inventory if they are mineralised.

“These are highly prospective targets: it’s just a matter of getting a drill rig onto them.”


This article was developed in collaboration with Chesser Resources, a Stockhead advertiser at the time of publishing.

 This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.