Great Southern chases platinum group elements with deep WA drilling

Great Southern Mining is probing deep at its East Laverton project in Western Australia, kicking off government co-funded diamond drilling to target a platinum group elements (PGE’s) discovery.

The program has started at the company’s Diorite Hill target, with the drill bit expected to reach up to a whopping 900 metres deep. 

Following completion of the hole, the rig will relocate to Great Southern’s Golden Boulder target area within its Duketon gold project to deliver the first-ever deep drilling at the gold discovery. 

The company says up to $337,500 in exploration incentive grants have been awarded through a competitive process for drilling, with the funding covering both the Diorite Hill hole and the Golden Boulder program. 

The diamond drilling at Diorite Hill is set to test two discrete reflective horizons identified from seismic surveys, which paint the prospect as a layered intrusive complex covering an extensive 110 square kilometres of rock sequences. 

These layered intrusive complexes are considered highly prospective for reef-style nickel-copper and PGE mineralisation. 

Great Southern says its target horizons mirror the world-class Merensky Reef in South Africa’s Bushveld Complex, displaying the same style of dense reflectors known to host rich platinum mineralisation — a key factor behind the government’s decision to include the project in its incentive scheme.

Local Western Australian analogues include the Munni Munni Complex in the Pilbara and the Chalice Mining-owned Gonneville Intrusion at Julimar, which holds a resource of 17 million ounces of PGE’s and 960,000 tonnes of nickel. 

The company says that earlier shallow exploration at Diorite Hill failed to reach these large-style blind targets, which will hopefully now be uncorked by the monster 900m hole. 

At Golden Boulder, the diamond drilling will target key structures believed to control the gold mineralisation outlined in shallow drilling at the discovery. This marks the first deep diamond work in the area, where previous reverse circulation holes rarely went below 150m. 

Standout intercepts from recent reverse circulation drilling at Golden Boulder include a 5-metre hit at a hefty 14.57 grams per tonne (g/t) gold from 41m, a 5-metre slice running 5.1g/t gold from 25m, and another 5-metre section grading 3.5 g/t gold from 39m.

The Golden Boulder target lies along a prominent structural corridor in the Duketon Gold Belt, host to several multi-million-ounce operations on nearby tenure. 

The diamond drilling will provide the first deep stratigraphic and structural data across the Rosemont Shear Zone on the company’s ground. 

Great Southern Mining managing director Matthew Keane said: “At East Laverton, a single diamond hole at Diorite Hill will test several dense stratigraphic horizons that seismic and magnetic surveys have shown do not propagate to surface. GSN’s geological team has likened these target horizons to the Merensky Reef of the Bushveld Complex in South Africa, known for its rich platinum mineralisation.”

The Duketon gold project is Great Southern’s focus within its WA strategy.

Across the country in Queensland, work programs are also ramping up to attack Great Southern’s big Edinburgh Park gold project.

The 1560-square-kilometre joint venture with Gold Fields has the gold mining giant spending $15 million on Great Southern’s ground to earn up to a 75 per cent interest by funding exploration.

The company initially outlined more than 25 high-priority targets across the big tenement package, focusing on potential large epithermal and intrusion-related gold systems, as well as porphyry-related gold-copper opportunities.

Drilling is scheduled to resume after the north Queensland wet season, likely in March, with initial plans calling for at least two deep diamond holes to test the core of a geophysical anomaly and beneath it. 

With diamond drilling now underway at Diorite Hill, before moving on to Golden Boulder, Great Southern is highly leveraged to further deep drilling discoveries. 

Notably, all of its Duketon projects sit within 40 kilometres of operating mills and major operations, giving the company a range of value-adding paths should a discovery emerge.

Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au