PRU.TO · 2023-08-23

Perseus Mining Announces Open Pit and Underground Ore Reserve Growth at Yaouré

Resource Estimates

23 AUGUST 2023

NEWS RELEASE

PERSEUS MINING ANNOUNCES OPEN PIT AND UNDERGROUND ORE RESERVE GROWTH AT YAOURÉ

Perth, Western Australia/August 23, 2023/Perseus Mining Limited (ASX/TSX: PRU) is pleased to announce an increase to CMA underground Ore Reserves beneath the existing CMA open pit, at its Yaouré Gold Mine in Côte d’Ivoire of 2.7 Mt at 3.46 g/t for 300 koz. The total CMA underground Ore Reserve is now estimated by Perseus to be 4.9 Mt at 3.51 g/t for 559 koz. The CMA orebody remains open down plunge and down dip below the current Indicated Mineral Resource, and further extensions to the CMA underground Ore Reserves are expected with future drilling during FY24.

Feasibility-level studies on the CMA deposit at Yaouré (approximately four hundred metres down dip from the base of the open pit) have confirmed the economic and technical viability of underground mining. Resource definition drilling during FY23 has added Mineral Resources and Ore Reserves down-dip of the CMA underground Pre-Feasibility Study (PFS) Ore Reserves and readers are referred to ASX release “Perseus Updates Mineral Resource and Ore Reserve Estimates” dated 28 August 2022 for additional details on the CMA underground PFS.

More widely spaced drilling below the CMA underground Ore Reserve has shown that mineralisation extends deeper allowing an extension to Inferred Mineral Resources at depth. Extension of Inferred Mineral Resources and continued drilling success down-dip, provides strong encouragement for further expansion of the CMA underground.

As well as growth to Ore Reserves for the CMA underground, a drill campaign of 22,084 metres during FY23 at the adjacent Yaouré open pit has resulted in 6.9 Mt at 1.82 g/t for 403 koz of additional Yaouré open pit Ore Reserves (separate to the CMA open pit). Yaouré open pit Ore Reserves now total 11.8 Mt at 1.49 g/t for 565 koz. The increase to Yaouré Open pit Ore Reserves is based upon conversion of Inferred Mineral Resources immediately beneath the existing Yaouré open pit to Indicated Mineral Resources.

CMA underground and Yaouré open pit Ore Reserve increases are in addition to the existing Ore Reserves, adding additional value and mine life to the Yaouré Gold Mine. The CMA underground Feasibility Study (FS) and the Yaouré open pit expansion will be released in Perseus’ upcoming Yaouré Gold Mine Life of Mine (LOM) plan.

HIGHLIGHTS

Indicated Mineral Resources at CMA underground have increased by 439 koz to 7.3 Mt at 4.17 g/t for 976 koz of contained gold, and Inferred Mineral Resources are estimated at 4.4 Mt at 3.4 g/t gold containing 485 koz of gold.
Underground Probable Ore Reserves estimated to date total 4.9 Mt of ore grading 3.51 g/t gold and containing 559 koz of gold, which is an increase for FY23 of 2.7 Mt at 3.46 g/t gold containing 300 koz of gold.
Yaouré open pit Indicated Mineral Resources have increased by 300 koz to 19.2 Mt at 1.27 g/t for 784 koz of contained gold, and Inferred Mineral Resources are estimated at 3.0 Mt at 1.3 g/t gold containing 124 koz of gold.
Yaouré open pit Probable Ore Reserves have increased in FY23 by 6.9 Mt at 1.82 g/t for 403 koz of gold, for a total of 11.8 Mt at 1.49 g/t gold containing 565 koz of gold.
Yaouré Gold Mine Ore Reserve increases at the CMA underground and the Yaouré open pit will extend the Yaouré Life of Mine (LOM) and all Ore Reserve additions are inside the mine fence and adjacent to the Yaouré processing facility. Perseus will prepare an updated LOM Plan for the Yaouré Gold Mine during the September 2023 Quarter.

PERSEUS MINING LIMITED
Level 2, 437 Roberts Road, Subiaco WA 6008
ABN: 27 106 808 986	1

Table 1: Yaouré Gold Mine Measured & Indicated Mineral Resources9,10,11

								MEASURED & INDICATED
		MEASURED RESOURCES			INDICATED RESOURCES
								RESOURCES
DEPOSIT	DEPOSIT TYPE
		QUANTITY	GRADE	GOLD	QUANTITY	GRADE	GOLD	QUANTITY	GRADE	GOLD
		Mt	g/t gold	’000 oz	Mt	g/t gold	’000 oz	Mt	g/t gold	’000 oz

CMA1,3,4, 6	Open Pit	-	-	-	16.7	1.32	710	16.7	1.32	710
Yaouré2,3,4, 6	Open Pit	-	-	-	19.2	1.27	784	19.2	1.27	784
Satellite deposits5,6	Open Pit	-	-	-	6.6	0.97	206	6.6	0.97	206
Sub Total		-	-	-	42.6	1.24	1,700	42.6	1.24	1,700
CMA8	Underground	-	-	-	7.3	4.17	976	7.3	4.17	976
Heap Leach3,7	Stockpile	-	-	-	0.4	0.61	8	0.4	0.61	8
Stockpiles	Stockpile	4.4	0.84	119	-	-	-	4.4	0.84	119
TOTAL		4.4	0.84	119	50.3	1.66	2,684	54.7	1.59	2,804

Table 2: Yaouré Gold Mine Inferred Mineral Resource^9,10

		INFERRED RESOURCES
DEPOSIT	DEPOSIT TYPE	QUANTITY	GRADE	GOLD
		Mt	g/t gold	’000 oz

CMA1,3,4, 6	Open Pit	2.6	0.7	58
Yaouré2,3,4,6	Open Pit	3.0	1.3	124
Satellite deposits5,6	Open Pit	1.3	0.8	34
CMA8	Underground	4.4	3.4	485
TOTAL		11.3	1.9	701

Notes:

1. Based on June 2022 Mineral Resource estimate.

2. Based on June 2023 Mineral Resource estimate.

3. Depleted for previous mining and to 30 June 2023 mining surface.

4. 0.4 g/t gold cut-off applied to in situ open pit material.

5. Based on Angovia 2 April 2021, Govisou June 2022, and CMA SW August 2022 Mineral Resource models.

6. In situ open pit resources constrained to US$1,800/oz pit shells.

7. Heap leach resources are stated at 0 g/t gold cut-off; only heap leach components with average grade above 0.4 g/t included.

8. June 2023 Mineral Resource estimate, below Stage 3 pit and above 1.5 g/t block grade cut-off.

9. Mineral Resources current as of 30 June 2023.

10. Rounding of numbers to appropriate precision may result in summary inconsistencies.

11. Mineral Resources are reported inclusive of Ore Reserves.

Table 3: Yaouré Gold Mine Ore Reserves^5,6

		PROVED			PROBABLE			PROVED + PROBABLE
DEPOSIT	DEPOSIT TYPE	QUANTITY	GRADE	GOLD	QUANTITY	GRADE	GOLD	QUANTITY	GRADE	GOLD
		Mt	g/t gold	’000 oz	Mt	g/t gold	’000 oz	Mt	g/t gold	’000 oz

CMA1,2	Open Pit	-	-	-	11.9	1.81	692	11.9	1.81	692
Yaouré2,3	Open Pit	-	-	-	11.8	1.49	565	11.8	1.49	565
Satellite deposits2,3	Open Pit	-	-	-	4.1	1.03	137	4.1	1.03	137
Sub-Total		-	-	-	27.8	1.56 1,394		27.8	1.56 1,394
CMA4	Underground	-	-	-	4.9	3.51	559	4.9	3.51	559
Stockpiles	Stockpile	4.4	0.84	119	-	-	-	4.4	0.84	119
TOTAL		4.4	0.84	119	32.8	1.85 1,953		37.2	1.73 2,072

Notes:

1. Based on depletion to 30 June 2023 mining surfaces.

2. Variable gold grade cut-offs for each material type, ranging from 0.35 g/t to 0.75 g/t.

3. Pit designs are based on US$1,300/oz gold price for satellites and US$1,500/oz for CMA and Yaouré open pit.

4. Based upon cut-off for development and stoping of 0.5 g/t and 2.5 g/t.

5. Inferred Mineral Resource is considered as waste for optimisation purposes.

6. Rounding of numbers to appropriate precision may have resulted in apparent inconsistencies.

Perseus’s Managing Director and CEO Jeff Quartermaine said:

“Since pouring first gold at Yaouré, this mine has repeatedly exceeded our expectations on almost every measure and made a very significant contribution to the success of our company. The discovery of extensions to the CMA orebody at depth and confirmation that these Mineral Resources can be economically developed is further evidence that not only is the Yaouré Gold Mine an outstandingly good operation, but that it will also continue to contribute benefits to all of our stakeholders, well beyond our initial estimates.

The results that have been announced today are associated with the first 400 metres down dip from the base of the CMA open pit. Three dimensional seismic surveys have confirmed that the CMA and associated structures continue at depth for a much greater distance underground and it will require further drilling to confirm that these structures are mineralised with economically mineable grades at depth. However, based on what we have seen to date, we are optimistic that once established, the underground operation at Yaouré will continue for many years into the future.

The Yaouré underground mine is Perseus’s first foray into underground mining, with all previous operations having been open cut operations. While this represents a new style of mining and a new challenge for us as a company, it is certainly not new to many of the technical staff that are currently employed by Perseus who are very keen to demonstrate their skills in an underground mining setting. This depth of talent within our existing ranks gives us every confidence that the Yaouré Underground operation, when it commences, will be every bit as successful as the open pit operation that has preceded it”.

INTRODUCTION

Perseus is currently mining the CMA orebody at the Yaouré Gold Mine in Côte d’Ivoire using conventional open pit mining methods. The CMA orebody is a tabular zone of mineralisation 2-20 metres thick which generally grades at 3- 7 g/t gold and generally dips to the east at 20-35 degrees but can be shallower or steeper locally. Perseus reported its first open pit Mineral Resource and Ore Reserve in the News Release “Perseus Confirms Quality of Yaouré Gold Project” dated 3 November 2017 based on a Feasibility Study. The open pit Feasibility Study identified the potential for the CMA orebody to extend to depth. This was confirmed by a Concept Study entitled “Perseus Mining Completes Scoping Study for Potential Underground Mine at Yaouré” dated 5 November 2018, which evaluated the potential to mine the orebody using underground mining methods and produced a maiden Mineral Resource estimate for the CMA underground.

In 2020, a 3D seismic survey was completed over a large volume around the CMA pit, that provided encouragement that the CMA orebody continued further down dip from the area assessed in the 2018 Concept Study. Based on the findings, drilling programs were instigated in 2021 to convert the identified underground Inferred Mineral Resource to an Ore Reserve and to investigate the potential to extend the underground Inferred Mineral Resource further down dip. The two drilling programs were completed in the first half of 2022 which culminated with a Pre-Feasibility Study and maiden Ore Reserve for the CMA underground and continued extension of the Inferred Mineral Resource down-dip. The two drilling programs also had a small impact on the open pit Mineral Resource, mainly on the resource classification. Based on the results of the Pre-Feasibility Study, drilling has continued through 2022 and 2023 to support the CMA underground Feasibility Study and expand upon the existing CMA underground Mineral Resource and Ore Reserve.

After accounting for mine depletion, the CMA open pit Mineral Resources and Ore Reserves are materially

unchanged from those previously stated. Please refer to release	to ASX release “Perseus Updates Mineral Resource
and Ore Reserve Estimates” dated 28 August 2019 for additional details.

OPEN PIT MINERAL RESOURCE

The combined 30 June 2023 Yaouré Gold Mine open pit Indicated Mineral Resources is 42.6 Mt at 1.24 g/t gold for 1.7 Moz and Inferred Mineral Resources of 6.9 Mt at 1.0 g/t gold for 216 koz.

The updated Yaouré open pit Mineral Resource estimate is 19.2 Mt at 1.27 g/t gold for 784 koz of Indicated Mineral Resources and 3.0 Mt at 1.3 g/t gold for 124 koz of Inferred Mineral Resources. The updated Yaouré open pit estimate includes an additional 22,084 metres in 130 drill holes targeting infill areas and high-grade lodes to delineate and increase the confidence of the Yaouré open pit Mineral Resource to support an updated Yaouré open pit Ore Reserve.

The updated CMA open pit Mineral Resource estimate is 16.7 Mt at 1.32 g/t gold for 710 koz of Indicated Mineral

Resources and 2.6 Mt at 0.7 g/t gold for 58 koz of Inferred Mineral Resources.	The CMA open pit Mineral Resource
estimate for the Yaouré Gold Mine has been depleted to the 30 June 2023 surveyed mining surface.

After accounting for mine depletion and adjustments for the underground Mineral Resource within the US$1,800/oz pit shell, the CMA open pit Mineral Resource estimate remains materially unchanged from the previous CMA open pit estimate reported at 30 June 2019 and readers are referred to ASX release “Perseus Updates Mineral Resource and Ore Reserve Estimates” dated 28 August 2019 for additional details.

The Yaouré Satellite Deposits open pit Mineral Resources remain materially unchanged from the previous Yaouré Satellite Deposits open pit estimate reported at 30 June 2019 and readers are referred to ASX release “Perseus Updates Mineral Resource and Ore Reserve Estimates” dated 28 August 2019 for additional details.

The Yaouré, CMA and Satellite Deposits open pit Mineral Resources are reported at a 0.4 g/t gold cut-off grade within a US$1,800/oz pit shell.

The CMA, Yaouré and Satellite Deposits open pit Mineral Resource estimates are reported in accordance with the 2012 Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC Code). The classification categories of Measured, Indicated and Inferred under the JORC Code are equivalent to the CIM categories of the same names (CIM, 2014).

The 30 June 2023 estimated open pit Mineral Resources at Yaouré Gold Mine are summarised in Tables 4 and 5 below.

Table 4: Yaouré Gold Mine Open Pit Measured & Indicated Mineral Resources^7,8

								MEASURED & INDICATED
		MEASURED RESOURCES			INDICATED RESOURCES
								RESOURCES
DEPOSIT	DEPOSIT TYPE
		QUANTITY	GRADE	GOLD	QUANTITY	GRADE	GOLD	QUANTITY	GRADE	GOLD
		Mt	g/t gold	’000 oz	Mt	g/t gold	‘000 oz	Mt	g/t gold	’000 oz

CMA1,3,5,6	Open Pit	-	-	-	16.7	1.32	710	16.7	1.32	710
Yaouré2,3,5,6	Open Pit	-	-	-	19.2	1.27	784	19.2	1.27	784
Satellite Deposits3,4,5,6	Open Pit	-	-	-	6.6	0.97	206	6.6	0.97	206
TOTAL		-	-	-	42.6	1.24	1,700	42.6	1.24	1,700

Table 5: Yaouré Gold Mine Open Pit Inferred Mineral Resource⁷

		INFERRED RESOURCES
DEPOSIT	DEPOSIT TYPE	QUANTITY	GRADE	GOLD
		Mt	g/t gold	’000 oz

CMA1,3,5,6	Open Pit	2.6	0.7	58
Yaouré2,3,5,6	Open Pit	3.0	1.3	124
Satellite Deposits3,4,5,6	Open Pit	1.3	0.8	34
Total		6.9	1.0	216

Notes:

1. Based on June 2022 Mineral Resource estimate.

2. Based on June 2023 Mineral Resource estimate.

3. Depleted for previous mining and to 30 June 2023 mining surface.

4. Based on Angovia 2 April 2021, Govisou June 2022, and CMA SW August 2022 Mineral Resource models.

5. 0.4 g/t gold cut-off applied to in situ open pit material.

6. In situ open pit resources constrained to US$1,800/oz pit shells

7. Rounding of numbers to appropriate precision may result in summary inconsistencies.

8. Mineral Resources are reported inclusive of Ore Reserves

YAOURÉ OPEN PIT MINERAL RESOURCE MATERIAL INFORMATION SUMMARY

A Material Information Summary is provided for the Yaouré open pit Mineral Resource pursuant to ASX Listing Rules 5.8 and 5.9 and the Assessment and Reporting Criteria in accordance with JORC Code 2012 requirements. The Assessment and Reporting Criteria in accordance with JORC Code 2012 (Table 1) is presented in Appendix 3.

GEOLOGY AND GEOLOGICAL INTERPRETATION

The CMA and Yaouré gold deposits occur near the south-eastern flank of the Bouaflé greenstone belt in central Côte d’Ivoire. Mineralisation is hosted by Paleoproterozoic-aged metabasalts and granodiorites of the Birimian Supergroup. The rocks are metamorphosed to lower greenschist facies and only locally feature penetrative deformation fabrics. Timing of the gold mineralisation event at Yaouré is dated to have occurred circa 2,105+4 Ma associated with crustal shortening.

Gold mineralisation is predominantly associated with quartz-albite-carbonate veining in reverse fault (Y) structures, forming a series of interconnected lodes with the best developed structures typically dipping at 25 to 30 degrees to the east. Gold mineralisation is also associated with extensional sub-vertical strike-slip fault (S) structures commonly orientated in a general east-west strike, in addition to the reverse fault structures (Appendix 1 – Figure 3). Gold is associated with disseminated pyrite within veins and altered wall-rocks. Arsenopyrite and molybdenite occur in trace quantities. No significant concentrations of other economic metals or deleterious elements are known to occur with the mineralisation.

The Yaouré open pit resource comprises thirty-two discretely modelled lodes with variable widths ranging from 1-3 metres up to 15-20 metres in approximate thicknesses. Fifty percent of the Indicated Resource ounces is hosted in eleven of the modelled lodes with the other fifty percent of the Indicated Resource ounces contained in the remaining lodes and background domains.

The Yaouré open pit Mineral Resource is currently defined to a maximum vertical depth of approximately 400 m from surface with Indicated Resources defined to an approximate depth of 250 metres and Inferred Resources defined to an approximate depth of 350 metres. The Mineral Resource extends over 1,500 metres in strike length.

DRILLING TECHNIQUES

The Yaouré open pit Mineral Resource estimate is informed by RC and diamond core intercepts in holes drilled between 2007 and 2015 by Amara Mining plc, and holes drilled from 2017 onward by Perseus Mining (Table 6). Fifty three percent of the drill hole metres that inform the Yaouré open pit resource estimate are comprised from diamond core samples.

Table 6: Yaouré Open Pit Resource Estimate Drilling Breakdown by Drill Type and Period

	No. Holes			Metres
Company
	RC	DD1	Total	RC	DD1	Total

Amara Mining	713	344	1,057	49,084.00	76,284.70	125,368.70
Perseus Mining	773	129	902	41,264.00	23,408.60	64,672.60
Total	1,486	473	1,959	90,348.00	99,963.30	190,041.30

1. DD figures include drill holes with RC pre-collars.

A total of 130 new drill holes for 22,084 metres are included in the updated 30 June 2023 Mineral Resource estimate compared with the previous Mineral Resource estimate. The 130 new drill holes targeted infill areas and high-grade lodes to delineate and increase the confidence of the Yaouré open pit Mineral Resource to support an updated Yaouré open pit Ore Reserve.

Drill hole collar locations were surveyed by qualified surveyors using total station or differential GPS equipment and reported in UTM Zone 30N with elevation converted to mine grid by adding 1,000 metres to the natural topographic datum height. Both RC and diamond core holes were down-hole surveyed at approximately 30 m intervals. Diamond core in fresh rock was routinely oriented.

DRILL COVERAGE

The Yaouré deposit is delineated by regular spaced drilling on an approximate 25 × 25 metre grid to a depth of between 200 and 250 metres below natural surface between 777,000 mN and 777,750 mN; and between 100 to 150 metres below natural surface between 776,500 mN and 777,000 mN. This drill spacing is considered sufficient to define Indicated Mineral Resources. Partial coverage is achieved at an approximate 50 × 50 metre spacing to approximately 300 and 350 metres below natural surface between 777,000 mN and 777,750 mN; and between 150 to 250 metres below natural surface between 776,500 mN and 777,000 mN. This drill spacing is considered sufficient to define Inferred Mineral Resources.

Holes have generally been drilled dipping at -55 to -75 degrees toward 270 degrees (UTM grid) azimuth, approximately orthogonal to the dip and strike of the reverse fault structures and drill intercept lengths closely approximate true widths of mineralisation for the reverse fault structures. Intercepts are typically oblique for the general east-west strike-slip fault structures with true widths approximately 65% of the intercept length. The 2023 drilling has been preferentially orientated where possible to intersect these structures at a more orthogonal angle.

Mineralisation remains open at depth.

SAMPLING

RC drill samples were collected over 1 metre intervals and split using multi-stage riffle splitters. Subsample weights were nominally 3 kilograms. For some Amara and most Perseus RC drilling, sample recovery was measured by weighing bulk recovered samples. For Amara and Perseus RC drill campaigns, samples were logged visually for recovery, moisture and contamination. The majority of Amara and Perseus RC samples were logged as dry and sample contamination in RC holes is not considered a significant risk to the reliability of the resource estimate.

Diamond core was sawn in half using a diamond blade saw, with one half sent for assaying and the other half stored in core trays for reference. Samples were normally taken over 1 metre intervals or shorter lengths to reflect sampling to geological contacts. For most Amara and Perseus core drilling, core recoveries were measured and considered reasonable with negligible core loss recorded.

SAMPLE ANALYTICAL METHODS

Samples were mainly prepared on site by Cluff, Amara and Perseus in a dedicated sample preparation facility. Sample preparation typically comprised drying, crushing to -2 millimetres and pulverising of a 1.5 kilogram subsample. Internal laboratory checks required at least 85% of the pulp passing -75 microns. The remainder of samples were prepared by commercial laboratories using nearly identical processes.

Assaying has been carried out by various commercial laboratories consistently using 50-gram Fire Assay (“FA”) technique with Atomic Absorption Spectroscopy (“AAS”) determination prior to 2023. Commencing in 2023 gold analysis has been conducted using the Chrysos PhotonAssay™ determination method at MSALABs in Yamoussoukro.

A consistent regime of quality assurance has been employed including submission of duplicate pulp samples, coarse blanks and certified reference materials.

ESTIMATION METHODOLOGY

Mineral Resources were estimated for gold using either Ordinary Kriging (OK) or Inverse Distance (ID) methods of 1 metre down-hole composited gold grades from RC and diamond drilling. The geological modelling and resource estimation was conducted using Leapfrog Geo™ software and the Edge™ module.

Discrete individual lodes (domains) were modelled using the interval selection tool and vein modelling function in Leapfrog Geo™. Domain intervals were selected based on geological characteristics of the mineralisation and a nominal cut-off grade of 0.2 g/t gold.

The estimation approach and estimate search strategy was chosen on an individual domain basis based on inputs criteria including the number of samples, drill hole spacing, lode (domain) orientation and variogram model analysis. Estimates were undertaken as hard boundaries into parent blocks with dimensions of 8.0 mE by 16.0 mE by 5.0mRL. The block size was selected based on drill hole spacing, the geometry of the mineralisation and the selective mining unit. Parent blocks were sub-blocked to 0.5 mE by 1.0 mN by 0.625 mRL to improve the volume definition of the domains.

Search ellipses were oriented to reflect the strike and dip directions of each of the lodes and where applicable dynamic anisotropy was applied. Top-cuts were applied based on an individual lode (domain) basis and ranged between 10 g/t to 40 g/t gold.

Bulk densities were applied to the block model by oxidisation type and lithology, with values of 1.80 t/m³ for completely weathered material, 2.10 t/m³ for transitional weathered material, 2.70 t/m³ for sediments in fresh material, 2.85 t/m³ for basalt in fresh material, 2.80 t/m³ for intrusive porphyritic dykes and 2.75 t/m³ for granodiorite.

Gold grade estimates were validated statistically by comparing mean composited grades to mean estimated grades, by gold grade trends in easting, northing and elevation Swath plots and by visual checks in Leapfrog.

RESOURCE CLASSIFICATION

Indicated Mineral Resources are confined to areas of approximately 25 metres by 25 metres drill coverage, with Inferred classified estimates in more broadly sampled mineralisation typically at a 50 metre by 50 metre drill coverage. Inferred Mineral Resources in places extend to a maximum of around 100 metres from drilling.

POTENTIAL FOR EVENTUAL ECONOMIC EXTRACTION

Mineral Resources comprise blocks with an estimated gold grade above 0.4 g/t Au, the average break-even cut-off grade that derives from cost and revenue parameters estimated in the Yaouré open pit Ore Reserve based on a gold price of US$1,800/oz.

There are no regulatory, environmental, or social impact considerations presently known that are likely to impact eventual economic extraction of the Mineral Resource.

The Mineral Resource estimate stated herein does not consider other modifying factors that might arise out of mine planning and design such as ore loss, mining dilution or other mineralised material that might be mined during general open pit production activities.

UNDERGROUND MINERAL RESOURCE

The CMA underground Mineral Resource estimate for the Yaouré Gold Mine has been updated to include all recent CMA resource drilling. The updated CMA underground Mineral Resource estimate is 7.3 Mt at 4.17 g/t gold for 976 koz of Indicated Mineral Resources and 4.4 Mt at 3.4 g/t gold for 485 koz of Inferred Mineral Resources.

The updated CMA underground resource estimate includes an additional 44,711.9 metres in 100 drill holes targeting the CMA lode to delineate and increase the confidence of the CMA underground Mineral Resource to support the updated CMA underground Ore Reserve. The CMA underground is reported below the CMA Stage 3 pit design at a 1.5 g/t gold cut-off grade.

The underground Mineral Resource estimates are reported in accordance with the 2012 Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC Code). The classification categories of Measured, Indicated and Inferred under the JORC Code are equivalent to the CIM categories of the same names (CIM, 2014).

The 30 June 2023 estimated underground Mineral Resource at CMA are summarised in Tables 7 and 8 below.

Table 7: CMA Underground Measured & Indicated Mineral Resource^2,3

								MEASURED & INDICATED
		MEASURED RESOURCES			INDICATED RESOURCES			RESOURCES
DEPOSIT	DEPOSIT TYPE
		QUANTITY	GRADE	GOLD	QUANTITY	GRADE	GOLD	QUANTITY	GRADE	GOLD
		Mt	g/t gold	’000 oz	Mt	g/t gold	’000 oz	Mt	g/t gold	’000 oz

CMA ¹ Underground - - - 7.3 4.17 976 7.3 4.17 976

TOTAL - - - 7.3 4.17 976 7.3 4.17 976

Table 8: CMA Underground Inferred Mineral Resource²

		INFERRED RESOURCES
DEPOSIT	DEPOSIT TYPE	QUANTITY	GRADE	GOLD
		Mt	g/t gold	‘000 oz

CMA¹Underground 4.4 3.4 485

Total 4.4 3.4 485

Notes:

1. June 2023 Mineral Resource estimate, below Stage 3 pit and above 1.5 g/t block grade cut-off.

2. Rounding of numbers to appropriate precision may result in summary inconsistencies.

3. Mineral Resources are reported inclusive of Ore Reserves

CMA UNDERGROUND MINERAL RESOURCE MATERIAL INFORMATION SUMMARY

A Material Information Summary is provided for the CMA underground Mineral Resource pursuant to ASX Listing Rules 5.8 and 5.9 and the Assessment and Reporting Criteria in accordance with JORC Code 2012 requirements. The Assessment and Reporting Criteria in accordance with JORC Code 2012 (Table 1) is presented in Appendix 3.

GEOLOGY AND GEOLOGICAL INTERPRETATION

The CMA Underground Mineral Resource comprises fifteen discrete lodes with typical thicknesses ranging from 2-3 metres up to 15-20 metres. Eighty-nine percent of the Indicated Mineral Resource tonnage and ninety-two percent of the Indicated Mineral Resource contained ounces is hosted in the principal CMA and bifurcated hangingwall lode (structure).

CMA underground Mineral Resource extends from the designed base of the CMA open pit to a maximum vertical depth of approximately 185 metres for Indicated Resources and 350 metres for Inferred Resources. The corresponding down-dip extents beneath the pit design base are approximately 400 metres and 700 metres. The Mineral Resource extends over 1,400 metres in strike length and mineralisation remains open along the moderately plunging trend to the north (Appendix 1 – Figure 5).

DRILLING TECHNIQUES

The CMA underground Mineral Resource estimate is informed by RC and diamond core intercepts in holes drilled between 2012 and 2015 by Amara Mining plc, and holes drilled from July 2017 onward by Perseus Mining (Table 9). Approximately ninety-seven percent of the CMA intercepts (below the CMA pit design) that inform the underground Mineral Resource estimate are comprised from diamond core samples.

Table 9: CMA Underground Resource Estimate Breakdown for Principal CMA and Hangingwall Lode by Drill Type and Period

	No. Holes			Metres
Company
	RC	DD1	Total	RC	DD1	Total

Amara Mining	21	66	87	5,156	23,815.26	28,971.26
Perseus Mining	-	388	388	-	137,582.00	137,582.00
Total	21	454	475	5,156	161,397.26	166,553.26

1. DD figures include drill holes with RC pre-collars.

A total of 100 new drill holes for 44,711.9 metres are included in the updated 30 June 2023 Mineral Resource estimate compared with the previous Mineral Resource estimate. The 100 new drill holes targeted infill areas and down-dip extension of the high-grade CMA lode to delineate and increase the confidence of the CMA underground Mineral Resource to support an updated CMA underground Ore Reserve.

DRILL COVERAGE

The CMA underground lodes are delineated by regular drilling at approximately 25 to 30 metres down-dip spaced holes to between 75 and 100 metres and approximately 50 to 60 metres down-dip spacing between 100 to 185 metres below the base of the CMA open pit. The drill spacing is considered sufficient to define Indicated Mineral Resources. Drilling coverage is at greater than 50 metres up to 100 metres spacing to approximately 350 metres below the base of the CMA open pit which is considered sufficient to define Inferred Mineral Resources.

Holes have generally been drilled dipping at -55 to -75 degrees toward 270 degrees (UTM grid) azimuth, approximately orthogonal to the dip and strike of the principal CMA lode, with drill intercept lengths closely approximate to true widths of mineralisation. In the CMA northwest lode, drill holes prior to 2023 are mostly oblique to the lode and the effective along-strike drill spacing is 40 to 50 m and mineralisation true width is approximately 65% of intercept length.

Mineralisation remains open at depth.

SAMPLING

RC drill samples were collected at drill sites over 1 metre intervals and split using multi-stage riffle splitters. Subsample weights were nominally 3 kilograms. For some Amara and most Perseus RC drilling, sample recovery was measured by weighing bulk recovered samples. For Amara and Perseus RC drill campaigns, samples were logged visually for recovery, moisture and contamination. The majority of Amara and Perseus RC samples were logged as dry and sample contamination in RC holes is not considered a significant risk to the reliability of the resource estimate.

SAMPLE ANALYTICAL METHODS

Samples were mainly prepared on site by Cluff, Amara and Perseus in a dedicated sample preparation facility. Sample preparation typically comprised drying, crushing to -2 millimetres and pulverising of a 1.5-kilogram subsample. Internal laboratory checks required at least 85% of the pulp passing -75 microns. The remainder of samples were prepared by commercial laboratories using nearly identical schemes.

Assaying has been carried out by various commercial laboratories consistently using 50-gram Fire Assay (“FA”) technique with Atomic Absorption Spectroscopy (“AAS”) determination prior to 2023. Since February 2023, gold analyses have preferentially been attained via the Chrysos PhotonAssay™ determination method at MSALABs in Yamoussoukro.

A consistent regime of quality assurance has been employed including submission of duplicate pulp samples, coarse blanks and certified reference materials.

ESTIMATION METHODOLOGY

Discrete individual lodes (domains) were modelled using the interval selection tool and vein modelling function in Leapfrog Geo™. Domain intervals were selected based on geological characteristics of the CMA mineralisation and a nominal cut-off grade of 0.5 g/t gold.

The estimation approach and estimate search strategy was chosen on an individual domain basis based on inputs criteria including the number of samples, drill hole spacing, lode (domain) orientation and variogram model analysis. Estimates were undertaken as hard boundaries into parent blocks with dimensions of 10.0 mE by 12.5 mE by 5.0 mRL. The block size was selected based on drill hole spacing, the geometry of the mineralisation and the selective mining unit. Parent blocks were sub-blocked to 0.625 mE by 3.125 mN by 0.3125 mRL to improve the volume definition of the domains.

RESOURCE CLASSIFICATION

Indicated Mineral Resources are confined to areas of approximately 25 up to 50 metres drill hole spacing coverage, with Inferred classified estimates in more broadly sampled mineralisation between approximately 50 to 100 metres drill hole spacing coverage. Inferred Mineral Resources generally extend to a maximum of around 50 metres from drilling.

Other general conditions taken into consideration in the classification are as follows:

Kriging Efficiency (KE)
Continuity of grades between drill holes
Confidence in the geological interpretation of mineralisation boundaries.

POTENTIAL FOR EVENTUAL ECONOMIC EXTRACTION

Mineral Resources comprise blocks with an estimated gold grade above 1.5 g/t gold, the average break-even cut-off grade that derives from cost and revenue parameters estimated in the CMA underground feasibility study and based on a gold price of US$1,800/oz.

There are no regulatory, environmental, or social impact considerations presently known that are likely to impact eventual economic extraction of the Mineral Resource.

OPEN PIT ORE RESERVE

The Ore Reserve for CMA open pit is summarised below in Table 10 and is based on the CMA Mineral Resources as

at 30 June 2023. Apart from depletion, the	CMA open pit and Yaouré satellite open pit Ore Reserve estimates
remain materially unchanged from the estimate reported at 30 June 2019 and readers are referred to ASX release
“Perseus Updates Mineral Resource and Ore Reserve Estimates” dated 28 August 2019 for additional details.
During FY23, Perseus has increased its Ore Reserve gold price to $1,500/oz from $1,300/oz, however for the CMA
open pit, there is no practical additional cutback at $1,500/oz relative to the pre-existing Ore Reserve design based
on a $1,300/oz pit shell and the design therefore remains unchanged.

The Ore Reserve for Yaouré open pit is reported within a pit design based on an optimised pit shell and cut-off grades at a $1,500/oz gold price. An increase of 6.9 Mt at 1.82 g/t for 403 koz of material has been added to the June 2022 Yaouré open pit Ore Reserve, for a total of 11.8 Mt at 1.49 g/t for 565 koz of probable Ore Reserves for Yaouré open pit. The combined open pit Ore Reserves for the Yaouré Gold Mine is now 27.8 Mt at 1.56 g/t for 1.4 Moz.

Ore Reserves are reported in accordance with the JORC Code and are reported by category, deposit and type, above variable cut-off grades. The classification categories of Proved and Probable under the JORC Code are equivalent to the CIM Proven Mineral Reserve and Probable Mineral Reserve categories respectively (CIM, 2010). Appendix 3 provides the JORC Table 1 criteria for the Yaouré open pit Ore Reserves.

Table 10: Yaouré Open Pit Proved and Probable Ore Reserves as at 30 June 2023^4,5

		PROVED			PROBABLE			PROVED + PROBABLE
	DEPOSIT
DEPOSIT		Quantity	Grade	Gold	Quantity	Grade	Gold	Quantity	Grade	Gold
	TYPE
		Mt	g/t gold	’000 oz	Mt	g/t gold	’000 oz	Mt	g/t gold	’000 oz

CMA1,2	Open Pit -	- - 11.9	1.81	692	11.9	1.81	692
Yaouré2,3	Open Pit	11.8	1.49	565	11.8	1.49	565
Near-Mine		4.1	1.03	137	4.1	1.03	137

Open Pit Satellite^2,3 Total - - - 27.8 1.56 1,394 27.8 1.56 1,394

Notes:

1. Based on depletion to 30 June 2023 mining surfaces.

2. Variable gold grade cut-offs for each material type, ranging from 0.35 g/t to 0.75 g/t.

3. Pit designs are based on US$1,300/oz gold price for satellites and US$1,500/oz for CMA and Yaouré open pit.

4. Inferred Mineral Resource is considered as waste for optimisation purposes.

5. Rounding of numbers to appropriate precision may have resulted in apparent inconsistencies.

CUT-OFF GRADES

Cut-off grades for the Yaouré open pit Ore Reserve range from 0.45 g/t to 0.75 g/t depending upon material type. Cut-off calculation revenues are estimated at a gold price of $1,500/oz. Cut-off grades are based on calculated grades and rounded up to the nearest 0.05 g/t.

Table 11: Yaouré Open Pit Ore Reserve Cut-off Grades

MATERIAL TYPE OXIDE TRANSITION YAOURÉ BASALT YAOURÉ GRANODIORITE Cut-off (g/t) 0.45 0.50 0.75 0.60

The cut-off grade for the Yaouré basalt fresh material type is significantly higher than for the fresh granodiorite due to the much lower processing rate for this material (2.5 Mt/y for basalt vs 3.2 Mt/y for the granodiorite).

Un-escalated average costs used in optimising pit designs are as shown in Table 12 below. A rate of 10% (real) has been assumed to discount cash flows.

Table 12: Average operating costs

1. MINING (OPEN PIT) 2. PROCESSING 3. G&A 4. SELLING 5. ROYALTIES¹

US$3.21/t mined US$17.28/t milled US$9.30/t milled US$3.05/oz sold 4.5%

Notes:

1. Includes 0.5% contribution to Community Development Fund.

MINING ASSUMPTIONS

The chosen method for the Open Pit Reserves is conventional open pit mining utilising hydraulic excavators and trucks, mining bench heights of 10 metres with 2.5 metre flitches to minimise ore loss and waste rock dilution.
The Yaouré open pit Ore Reserve is based upon a reblocked version of the Yaouré open pit Mineral Resource model. The Ore Reserve model has been reblocked to 4.0 m × 4.0 m × 2.5 m block size, which introduces a dilution of 8% additional ore tonnes for 11% reduction in grade and mining recovery of 96% of ounces relative to the sub-blocked Mineral Resource model.
The economic pit shell was defined using Whittle pit optimisation software (“Whittle”) with inputs such as geotechnical parameters, metallurgical recovery and mining costs.
The pit optimisation was run with revenue generated only by Measured and Indicated Mineral Resources. No value was allocated to Inferred Mineral Resources.
Whittle input parameters are based on Perseus site operating experience in similar deposits at Yaouré and supporting technical studies undertaken as part of the Yaouré Feasibility study.
The pit slope designs are based on a geotechnical study by Pitt & Sherry Consultants. Inter-ramp slope angles are 30 to 40 degrees inclusive of berms spaced at 10 metres vertically and berm widths of 4.5 to 7 metres.
Pit ramps have been designed for a 100-tonne payload truck fleet and are set at 24 metres (dual lane) to 16 metres (single lane). Minimum mining width is 40 metres for the 100-tonne class truck fleet.
Vertical mining advance has been capped based on Perseus’s operating experience.
No environmental issues are known to exist which will prevent open pit mining and ore processing to continue to operate.
Perseus has ongoing studies to update the Yaouré waste dump and tailings dam designs, to include the new Yaouré open pit Ore Reserves, however we are not aware of any reason why such additional capacity will not be sufficiently available on site. Capacity on site is permitted for the required volumes of waste and tailings.

PROCESSING PARAMETERS

The process metallurgical recovery for gold is fixed by material type in each deposit. Gold recovery rates range from 92.6% for the fresh Yaouré basalt ore to 93.8% for the Yaouré granodiorite ore. Recovery is shown in Table 13.
No deleterious material has been identified.
Average annual processing throughput rate of ore is 3.9 Mt/y for oxide and transitional ore and 2.5 Mt/y and 3.2 Mt/y for Yaouré basalt and Yaouré granodiorite respectively. The processing circuit comprises crushing, grinding, gravity and cyanide leaching to extract gold.

Table 13: Metallurgical Recoveries by Material Type and Pit

	METALLURGICAL RECOVERIES BY ORE TYPE (%)
DEPOSIT
	Oxide	Transition	Fresh Basalt	Fresh Granodiorite

Yaouré 93.0 93.3 92.6 93.8

CRITERIA FOR ORE RESERVE CLASSIFICATION

Ore Reserves have been classified based on the underlying Mineral Resource classifications and a Feasibility level study for the Yaouré Gold Mine. Mineral Resources were classified as Indicated and Inferred. The Ore Reserves, based only on the Indicated Resources, have been classified as Probable Ore Reserves, respectively.

The Ore Reserve is classified as Probable in accordance with the JORC Code, corresponding to the Mineral Resource classification of Indicated and taking into account other modifying factors where relevant.

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