Great Southern Mining : EM CONDUCTORS IDENTIFIED AT EAST LAVERTON NICKEL PROJECT

ASX: GSN

ASX ANNOUNCEMENT

8 December 2021

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EM CONDUCTORS IDENTIFIED AT EAST LAVERTON NICKEL PROJECT

Great Southern Mining Limited (ASX: GSN, the "Company" or "GSN") is pleased to announce that the EM survey at the Company's 100%-owned East Laverton Nickel Project in Western Australia has identified significant bedrock conductors.

Highlights

• Multiple bedrock EM anomalies identified by the recent MLEM survey.
• The largest anomaly has been modelled by Newexco as a large (2km x 1km) sub-vertical conductor of 1,000 siemens at a depth of approximately 300m.
• The Project is considered highly prospective for nickel-sulfide discoveries with the prominent modelled bedrock conductor close to the edge of the interpreted Diorite Hill magmatic complex, which is a favourable position for massive sulfide accumulation.
• The conductor is also coincident with the edge of a regional gravity anomaly, further upgrading the potential for a blind nickel sulfide discovery.
• A follow-up, tighter spaced EM survey is under design to refine the geometry of the modelled conductors ahead of drill testing as soon as practical.

Figure 1 - Channel 30 linear colour stretch image showing the south-east conductor at station 76 relative to the Diorite Hill magmatic complex (red outline), overlayed with GSWA magnetics and interpreted ultramafic units.

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GSN's Chief Executive Officer, Sean Gregory, commented:

"This is an exciting development for GSN and is part of our overall strategy to progress exploration opportunities on multiple fronts. Although our primary focus is gold, GSN has identified the East Laverton Project as highly prospective for nickel-sulfide discoveries. This recent MLEM survey was the first modern ground-based EM survey over Diorite Hill and has identified a bedrock conductor in a favourable geological environment that represents a very intriguing target. We are very pleased with the results of this initial survey which justify close spaced EM and drill testing as soon as practical."

MLEM Survey Design

The Moving-LoopElectro-Magnetic (MLEM) survey was the first of its kind over the Diorite Hill magmatic complex. The survey involved laying wide spaced 200m square transmitter loops and taking soundings 600m from the loop centers at four points of the compass (Figure 1). This process was repeated at 55 transmitter locations across the Diorite Hill Magmatic Complex on a 1200m x 1200m spacing totaling 220 soundings covering 70km2.

The survey was designed and modelled by Bill Amann from leading exploration and geophysical consultants Newexco Exploration Pty Ltd (Newexco), who have been instrumental in the discovery of numerous major nickel sulfide deposits in Western Australia over the last 20 years including Flying Fox, Spotted Quoll and Nova.

Anomalies and Conductors Identified

The initial broad spaced MLEM survey returned adequate data that identified four Electro-Magnetic (EM) anomalies consistent with possible bedrock conductors. These four survey stations were then subject to infill soundings that enabled three bedrock conductors to be modelled (Figure 2).

Figure 2 - Channel 30 (late time) linear colour stretch showing conductors modelled.

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The strongest anomaly was identified in the south-east of the survey area. Loop 76 was of particular interest as this loop, and the adjacent loop, returned what appears to be exponential late time decays on all 8 soundings. (Figure 2).

An infill survey using one profile at Loop 76 was completed to assist in delineating the source of the anomaly. Preliminary interpretation produced a large bedrock conductor at depthwith a north-east orientation (Table 1 and Figure 3). Modelling is ongoing.

Table 1 - Anomalies and conductors modelled at Diorite Hill

	Anomaly	Model size	Depth to top	Conductivity thickness
				time constant
	76	2,000 x 1,000 m	300 m	1,000 Siemens 80ms
	101	No significant conductor able to be modelled
	124	300m x 300 m	300 m	500 Siemens 30ms
	149	100m x 100 m	100 m	100 Siemens 3ms

Figure 3 - South-east modelled EM bedrock conductor relative to the Diorite Hill magmatic complex, overlayed with GSWA gravity and GSWA interpreted ultramafic units. Insert highlights the preliminary modelled bedrock conductor.

The prominent bedrock conductor identified is in close proximity to the edge of the interpreted Diorite Hill magmatic complex, which is a favourable position for massive sulfide accumulation. Regional gravity data clearly highlights the Diorite Hill magmatic complex with the EM conductor positioned on the edge of the gravity high (Figure 3). This further upgrades the prospectivity and the significance of the bedrock conductor highlighting the potential for a blind discovery.

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Next Steps

The south-east portion of the survey area is of main interest and final modelling of the data is ongoing. Newexco have recommended that a closer spaced EM survey will further refine the orientation of the newly identified bedrock conductors ahead of drill testing as soon as practical. The survey will also extend south to examine if any other conductive sources are present.

The release of this ASX announcement was authorised by the Executive Chairman on behalf of the Board of Directors of the Company.

For Further Information Contact:

John Terpu

Executive Chairman

[e-mail]

[phone]

About East Laverton Nickel Project

The East Laverton Nickel Project is dominated by the Diorite Hill magmatic complex (Diorite Hill), Diorite Hill covers an area of approximately 110km2 and consists of a thick (7 km) cumulate rock sequence of interlayered peridotites, pyroxenites, gabbros and anorthosites. The southern and eastern part of the complex is contained within the project area.

Diorite Hill intruded a greenstone volcanic rock sequence indicated by the presence of non-cumulate mafic/ultramafic hornfels xenoliths within the complex. Diorite Hill is commonly covered by shallow modern aeolian sands that have hampered previous exploration. Diorite Hill is abutted to the south by the Rotorua Komatiite, a 10km by 1.5km extrusive ultramafic. The Curara Komatiite is further to the east.

Komatiites flows have been the main source of developed nickel-sulfide mines in WA and have been explored extensively since the late 1960's. Due to their well understood geochemistry, formation, and high-grade sulfide enrichment process within defined channels, most of the studies and exploration programs in WA have focused on discovering this style of mineralisation. The Kambalda-Kalgoorlie-Leinster-Laverton Goldfields Region has been the main focus for komatiite exploration, with limited potential existing outside this region. Greenfields discoveries of komatiite nickel have reduced in recent years in the Goldfields Region and its only deep brownfields exploration that is delivering new nickel deposits.

Elsewhere around the world, large scale magmatic nickel deposits are the common place, producing world- class deposits with long productive mine lives. In WA, magmatic nickel deposits occur scattered throughout the state, however, they have had a long and slow history of discovery, development and understanding.

Its only in recent years, since the 2012 discovery of the Nova-Bollinger 13Mt @ 2% Ni 0.8% Cu and 0.1 % Co deposit in the Fraser Range, that a string of magmatic nickel deposit have suddenly been discovered. As komatiite sources dry up, focus and understanding around magmatic nickel deposits is starting to gain momentum, resulting in exploration companies looking at various mafic-ultramafic bodies which have had limited to no exploration completed over them to date. This is resulting in a new level of understanding in WA on the formation/deposition of nickel-copper sulfides within magmatic rocks, leading to a wave of new discoveries.

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Interest in magmatic nickel-copper deposits have had a resurgence with the recent discoveries of magmatic hosted sulfide mineralisation at Chalice Gold Mines' (ASX:CHN) Julimar Project. It is this "Voisey Bay" magmatic style model has not been adequately explored at Diorite Hill. This represents a compelling exploration target opportunity which the Company intends to aggressively pursue.

About Great Southern Mining

Great Southern Mining Limited is a leading Australian listed gold exploration company. With significant land holdings in the world-renowned gold districts of Laverton in Western Australia and Mt Carlton in North Queensland, all projects are located within 25km of operating gold mills and major operations.

The East Laverton Nickel Project is located 15km east from the town of Laverton in Western Australia where GSN maintains an exploration base to service its significant exploration portfolio in the region, including the Southern Star Gold Deposit within the Duketon Gold Project to the north and the Mon Ami Gold Project south of Laverton.

The Company's focus is on creating shareholder wealth through efficient exploration programs and strategic acquisitions of projects that complement the Company's existing portfolio of quality assets.

For further information regarding Great Southern Mining Limited please visit the ASX platform (ASX:GSN) or the Company's website www.gsml.com.au.

Figure 4 - GSN's Laverton tenure and projects over GSWA TMI magnetics.

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