New airborne magnetic data and previous rock chip assays results have greatly enhanced the prospectivity of the Gladstone, Greenobbys and Boda South prospects at Impact Minerals Limited's (ASX:IPT) 100% owned Commonwealth project in the Lachlan Fold Belt in New South Wales.

In addition very high grade silver as well as gold results from Gladstone and Greenobbys have brought back into focus the fact that Impact's ground holdings cover an exceptionally silver-rich part of a mineral province best known for its major copper-gold deposits such as Cadia-Ridgeway, North Parkes and the recent discovery at Boda.

For example, Impact's Commonwealth and Silica Hill deposits contain bonanza grades of silver in both massive sulphide lenses as well as in epithermal veins, an important factor to consider given the current resurgence in the silver price. Some key results from these deposits are also reviewed in this report as part of a reassessment of the entire Lachlan portfolio for its silver potential.

Previous Work by Impact

The Gladstone, Greenobbys and Boda South prospects were identified together with the Apsley and Spicers Creek prospects by Impact as priority areas for follow up exploration following the BodaKaiser discovery in late 2019.

At the Apsley, Spicers Creek and Boda South prospects significant porphyry copper gold potential has been demonstrated because each prospect has characteristics commonly seen around giant alkaline porphyry copper-gold systems globally such as Cadia-Ridgeway and Boda. These include: Copper-bearing high potassium alkaline (shoshonite) host rocks of Ordovician age; metal assemblages and alteration minerals characteristic of the outer to inner zones of porphyry systems and an association with magnetic anomalies that may represent 'skarn' alteration directly associated with copper-gold mineralisation as also seen at Boda.

None of these prospects has been drilled. The results of a detailed soil geochemistry survey at Apsley have recently been received and are being interpreted.

At Greenobbys, Impact has identified high grade epithermal gold-silver mineralisation that is much younger than the porphyry copper-gold mineralisation and which has not been extensively explored for in the entire region.

Here, rock chips returned up to 9.5g/t gold (six samples with more than 1 g/t gold) and 215 g/t silver (7 ounces of silver with four samples containing more than 1 ounce per tonne) from veins of Kfeldspar and quartz. In addition the veins contain a remarkable array of pathfinder metals in particular bismuth (up to 745 ppm), molybdenum (up to 519 ppm) and tellurium (up to 40 ppm), together with appreciable amounts of the pathfinder metals selenium-thallium-antimony-arsenic-lead-barium and tungsten (ASX Release 23rd June 2020).

All of these features are interpreted to indicate the veins are related to fluids released from a potassium rich granite and which may represent a 'telescoped' epithermal system covering at least several hundred square metres. The veins are open along trend and at depth as there is no recorded drilling in the area.

Telescoping refers to the significant overlap between proximal and distal metal and mineral assemblages and suggests the possible rapid collapse of the parent hydrothermal system. This is encouraging for the discovery of bonanza gold -silver veins. The Gladstone target has been very poorly explored and Impact has only recently started to compile the scant previous exploration data as outlined below.

New Airborne Magnetic Data

Impact recently completed a detailed airborne magnetic and radiometric survey over the western parts of the Commonwealth project area at 50 metre line spacing. This has allowed new insights into the geology and structure of the area and a detailed interpretation of the data is in progress.

At Gladstone the new magnetic data has identified two key areas for follow up work. First, it is now evident that the southern extension of the Boda Intrusive Complex extends for up to 1,000 metres on to Impact's tenements from ground held by Magmatic Resources Limited (ASX:MAG) immediately to the north.

A rock chip sample taken by Newcrest Mining Limited at the edge of this structure in 1996 returned chip results from a quartz vein of 9.9 g/t gold, 3.2% copper and an exceptional silver result of 4,550 g/t silver. Of note, the vein occurs in Devonian rocks and may be of a similar age and silver-rich nature to those at Greenobbys. Small workings and diggings are present along the structure for a few hundred metres. This has never been followed up. Two other rock chips samples taken 750 metres east returned 0.8 g/t gold and at Gladstone East an assay of 1.8 g/t gold was returned. There was no significant silver at these prospects.

At Greenobbys the new magnetic data shows that the vein system occurs at the margin of a magnetic granite called the Wuuluman Granite (Carboniferous age). There are indications of the NW trending structures in the data. Of note is a north west trending magnetic low that is up to 500 metres thick and lies about 1 kilometre south of the vein system at Greenobbys. This is a clear zone of destruction of magnetite by hydrothermal fluids which has never been explored and is a priority area for follow up field checking.

Together, Gladstone and Greenobbys indicate an emerging region for high grade gold and silver epithermal mineralisation in rocks much younger than those that host the porphyry copper-gold mineralisation. Impact has extensive ground holdings for this style of mineralisation.

At Boda South the new magnetic data confirms that the southern end of the Boda Intrusive Complex (BIC) that controls the porphyry copper-gold mineralisation at Boda-Kaiser extends on to Impact's tenements. The magnetic units are associated with a marked curvilinear structure that may represent the edge of the original intrusive complex. Given the prospective nature of the BIC, modelling of magnetic data is required to determine the depth to the intrusive complex at Boda South and this is progress.

HIGH GRADE SILVER AT THE COMMONWEALTH AND SILICA HILL DEPOSITS

The Commonwealth and associated Silica Hill deposits occur in the centre of Impact's Commonwealth project and comprise a high sulphidation volcanogenic massive sulphide deposit and an epithermal gold-silver deposit respectively. Both deposits are characterised by exceptional silver grades.

Impact has defined Inferred Resources at these two deposits that contain 88,000 ounces of gold and 3.3 million ounces of silver from surface to a depth of 250 metres, well within the range of open pit mining (ASX Release 22nd August 2018).

Commonwealth (Main Shaft to Commonwealth South) comprises an Inferred Resource of 912,000 tonnes at 2.4 g/t gold, 44 g/t silver, 1.2% zinc and 0.5% lead including 142,000 tonnes at 4.5 g/t gold, 161 g/t silver, 4.6% zinc and 1.7% lead in the high grade massive sulphide lens at Main Shaft.

Silica Hill, which was discovered by Impact comprises an Inferred Resource of 710,000 tonnes at 0.8 g/t gold and 88 g/t silver.

The resources are open along trend and at depth and extensive further resource definition and extensional drilling is required to follow up key intercepts at Main Shaft and Silica Hill as outlined below.

At Main Shaft the massive sulphide lens is still open at depth and along trend to the north and south east. For example, the resource is open to the north down plunge from drill hole CMIPT084 and at depth below drill hole CMIPT021.

Hole CMIPT084 returned: 5.7 metres at 3.8 g/t gold, 347 g/t silver, 10.8% zinc and 3.7% lead from 52.1 metres down hole; including 0.7 metres at 15.6 g/t gold, 245 g/t silver, 8.6% zinc and 1.9% lead and 0.5 metres at 4.9 g/t gold, 917 g/t silver, 10.2% zinc and 4.6% lead from 56.9 metres.

Hole CMIPT021 returned: 8.1 metres at 6 g/t gold, 193 g/t silver, 5.9% zinc, 2.3% lead and 0.16% copper from 71 metres including 2.9 metres at 9.3 g/t gold, 201 g/t silver, 11.6% zinc, 4.7% lead and 0.2% copper.

At Silica Hill, a virgin discovery by Impact located 60 metres to 250 metres north east of Main Shaft mineralisation comprises high grade veins and disseminations of sulphide with gold and extensive visible silver minerals (antimony and arsenic sulphosalts: proustite-pyrargyrite). These minerals are exceptionally rare in Australia and contribute to some exceptional silver grades in specific veins.

There are also zinc and lead credits to the mineralisation at Silica Hill with the sulphides present being similar to those at Commonwealth-Main Shaft. They are interpreted as being part of the same overall mineralised system.

The disseminated mineralisation between the veins has helped form thick zones of near-surface modest grade mineralisation with the potential for bulk open pit mining. For example discovery hole CMIPT011 returned bonanza-grade silver within a sulphide vein in a thick zone of silver-gold mineralisation as follows: 48.6 metres at 137 g/t silver (4.4 ounces) and 0.5 g/t gold from 122 metres down hole, including, 23 metres at 224 g/t silver (7.2 ounces) and 1.0 g/t gold from 147.7 metres, which includes 0.9 metres at 3,146 g/t silver (101 ounces) and 2.4 g/t gold from 148.1 metres

Three diamond drill holes have also established that there is a low grade silver halo of up to 10 g/t silver around the Silica Hill mineralisation that is at least 500 m by 500 m in dimension. For example Hole CMIPT072 returned 146 metres at 0.04 g/t gold and 5 g/t silver. In addition CMIPT078 drilled at the eastern end of the northern mineralised zone returned the thickest intercept of gold and silver to date in this zone and indicates improving grades to the east and returned: 117 metres at 0.3 g/t gold and 11 g/t silver.

This attests to the scale of the mineralised system at Silica Hill which is still open in all directions and further deeper drilling is required.

The Eskay Creek gold-silver-base metal deposit

Impact's work at Commonwealth-Silica Hill has demonstrated compelling similarities to the world class Eskay Creek deposit in the famous 'Golden Triangle' of northern British Columbia, Canada. Gold, silver and base metal mineralisation was first found in the Eskay Creek area in 1932 with sporadic exploration in the intervening 50 years before the discovery of the main Eskay Creek orebody in 1988. The deposit is the type example of a 'high sulphidation volcanogenic massive sulphide (VMS) deposit', a style of depoist only recognised in the past 30 years.

Over its 14 year mine life Eskay Creek produced approximately 3.3 million ounces of gold and 160 million ounces of silver from 2.2 million tonnes of ore at average grades of 45 g/t gold and 2,224 g/t silver. It was once the world's highest-grade gold mine and fifth-largest silver mine by volume. Cut-off grades ranged from 12 to 15 g/t AuEq for mill ore and 30 g/t AuEq for direct shipping smelter ore.

In the past two years TSX:V listed company Skeena Resources Limited (TSX.V:SKE) has started to re-explore at Eskay Creek and the surrounding area and considerable attention has been aroused from some outstanding drill intercepts from remnant ore positions in the mine.

The similarities between Commonwealth, also interpreted as a high sulphidation VMS, and Eskay Creek include the host rocks and the style and type of mineralisation and pathfinder metals present (gold, silver sulphosalts, zinc, lead, extensive barite and lesser arsenic and antimony). In particular the units and veins of high grade gold and exceptionally high grade silver noted above are also characteristic.

Furthermore, Commonwealth and Eskay Creek have the same very well developed alteration mineral assemblage that show the same very clear timing relationships of early silica-pyrite-K feldspar progressively overprinted by sericite and then chlorite.

NEXT STEPS

The new magnetic data and previous exploration results by Impact and others strongly support the potential for the Commonwealth Project to host not only significant porphyry copper-gold deposits but also intrusion-related epithermal gold-silver deposits and volcanogenic massive sulphide deposits. Further work is now required to refine and rank these target areas for drilling. At present the Apsley target is ranked as the most prospective target for porphyr copper gold mineralisation and the results of a detailed soil geochemistry survey is now in progress.

In addition, a detailed interpretation of the new airborne magnetic and radiometric survey is also in progress together with a review of previous exploration data. All of this new data will be interpreted and synthesised to help define follow up work programmes which will include drilling later in 2020.

Contact:

Tel: (61 8) 6454 6666

Email: info@impactminerals.com.au

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