Great Southern Mining : Large EM conductor confirmed at East Laverton Nickel Project

ASX: GSN

ASX ANNOUNCEMENT

9 March 2022

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Large EM Conductor confirmed ready for drill testing at the East Laverton

Nickel Project

Great Southern Mining Limited (ASX: GSN) (the "Company" or "GSN") is pleased to announce an infill Fixed- Loop Electro-Magnetic (FLEM) survey has confirmed bedrock conductors at the Company's 100%-owned East Laverton Nickel Project (Project) in Western Australia.

Highlights

• The largest anomaly has been modelled by consultants, Newexco Exploration, as a large (2km x 1km) sub-vertical conductor of 1,000 siemens at a depth of approximately 360m.
• This prominent modelled bedrock conductor is in close proximity to be the edge of the interpreted Diorite Hill Magmatic Intrusion, which is a favourable position for massive sulfide accumulation.
• The geology of the Project area has potential to host Nova-Bollinger style nickel deposits with the project providing GSN transformational discovery potential.
• Review currently underway by highly experienced nickel consultant Dr Jon Hronsky looking at the nickel and platinum-group element potential of the Project.
• Programme of Work approved ahead of drill testing, estimated to commence in April 2022.

Figure 1 Diorite Hill Magmatic complex (red oval magnetic response), highlighting newly identified conductors overlayed with GSWA magnetics and interpreted basal contact.

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GSN's Executive Chairman, John Terpu, commented:

"The new FLEM survey has produced a compelling large conductor in close proximity to be the edge of the interpreted Diorite Hill magmatic intrusion. The geology of the project area is what sets this project apart from other nickel projects in Western Australia, as it has the potential to host magmatic nickel deposits like the Nova-Bollinger style deposit. These deposits generally produce large conductors and that's what we have now confirmed at East Laverton. We will be drill testing the large conductor as well as another more discrete conductor positioned in the middle of the intrusion as soon as all the approvals are in place. We are also planning further EM surveys along what is referred to as the Rotorua complex which is a fertile ultramafic that is yet to have any effective drill testing. The East Laverton Nickel Project is progressing well and is part of GSN's strategy to look at all opportunities to create shareholder value through discoveries."

Technical Discussion

This announcement relates to the completion and interpretation of a follow up FLEM survey carried out between the 2nd and 12th February 2022, over anomalies L076 and L124 at the East Laverton Nickel Project.

Leading exploration and geophysical consultants Newexco Exploration identified numerous soundings that returned anomalies during the initial survey (see ASX dated 08/12/2021). This survey has updated the interpretation, modelling and accuracy around the anomalies.

The large compelling anomaly (L076), interpreted to be located on or near the boundary the Diorite Hill mafic intrusive, is a favourable position for massive sulfide accumulation. The infill survey enabled the conductor to be sufficiently modelled with a proposed drill design now complete. A 600m drill hole has been planned to test the interpreted bedrock conductor. This hole targets a 2km x 1km plate modelled at various dips with an estimated depth-to-top of around 360m.

The newly identified conductor's location led to a recent re-evaluation of the historical work and the position of the basal contact is now interpreted on the south-west margin of the intrusion and the company is targeting this contact for nickel-copper accumulations of the same style as the Nova-Bollinger and Voisey Bay Nickel deposits.

This interpretation is significant from a prospectivity review as nickel sulphide orebodies are often associated with the basal contact as this is a favourable position for metal settling and accumulation.

Remarkably, virtually no historical nickel-copper exploration has been conducted over the complex in general and no drilling has taken place at the location of the large conductor.

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Figure 2 Detailed magnetics with interpreted basal contact, highlighting the proximity of the newly modelled large conductor

L076. Drillhole database displaying Newmont significant intersections along the Rotorua complex.

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A smaller but significantly isolated anomaly L124, located proximal to a magnetic source within the interpreted intrusive, has been modelled and is also recommended for further work.

The bedrock anomaly is evident on early times and was modelled by Plate L124 which is located at 467265mE 6838340mN -30m depth dipping at 80 to 045 degrees with a nominal size of 200m X 200m and 500S conductance. This is anomalous for this survey and is considered a favourable position for platinum- group elements (PGE) enrichment. The conductor is worthy of follow-up and should be able to be intersected with a small Reverse Circulation (RC) drill program.

Figure 3:L124 with detailed aeromagnetic image showing bedrock conductor in green.

In 2005 Newmont Australia ("Newmont") completed an aircore (AC) drilling program comprising 107 AC holes (BRAC001 - 31, 33 - 108) for 5,816m targeting the eastern part of the Merideth Shear and several linear magnetic features, one of which was the Rotorua ultramafic magnetic feature (Figure 2). The western margin of the complex was intersected in several drill lines with significant Ni enrichment in laterite with a peak 1m Ni intersection of 0.30% Ni was received (BRAC004, 23-24m, end of hole). Newmont were focused on gold exploration at the time, and little discussion is given to either the ultramafics intersected or the Ni mineralisation.

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The Rotorua unit has had very little nickel exploration and GSN have identified this unit to also be prospective for nickel sulphide deposition with komatiite style mineralisation the focus. A planned EM survey over the Rotorua complex in conjunction with Newexco has taken place and is currently under review.

Next Steps

The south-east portion of the survey area is of main interest, Newexco have designed a 600m deep drill hole to test the interpreted bedrock conductor (L076) as shown on Figure 2 and Figure 4. This hole targets a plate modelled at various dips with a depth to top of conductor around 360m, the hole is aimed well below this to avoid drilling over the top of the conductor.

A 500m RC drill program has been planned to target conductor L124.

A review of the East Laverton Project which is dominated by the Diorite Hill Layered Ultramafic Magmatic Intrusion and the adjoining Rotorua complex is underway by highly experienced nickel consultant Dr Jon Hronsky.

Figure 4:Section showing range of models with intersection of conductor 076 at around 450m below surface and at 515mdh

in the planned drill hole.

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