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G Mining Ventures Delivers Robust Feasibility Study For High-Grade Oko West Gold Project in Guyana

Economic Studies

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April 28, 2025

G Mining Ventures Delivers Robust Feasibility Study

For High-Grade Oko West Gold Project in Guyana

• After-tax NPV5% of $2.2 billion, IRR of 27% and payback of 2.9 years at $2,500/oz base case gold

price (long-term consensus)

• After-tax NPV5% of $3.2 billion, IRR of 35% and payback of 2.1 years at $3,000/oz gold price

• Average annual gold production of 350,000 ounces at an AISC of $1,123/oz for 12.3 years

• Initial capital cost of $972 million and sustaining capital of $650 million over the life of mine

• Early works construction progressing well after receipt of Interim Environmental Permit

• Final Environmental Permit expected in Q2-25, targeting construction decision in H2-25

• An average of 1,270 direct permanent jobs to be created from the Oko West Project

BROSSARD, QC, April 28, 2025 – G Mining Ventures Corp. (“GMIN” or the “Corporation ”) (TSX: GMIN,

OTCQX: GMINF) is pleased to announce the results of its Feasibility Study ( the “FS” or the “Study”) for the

development of its wholly-owned Oko West Gold Project (“Oko West” or the “Project”), located in Region

7, Guyana. Unless otherwise stated, all dollar amounts in this news release are expressed in U.S. dollars.

The FS confirms robust economics for a low-cost, large-scale, conventional open pit (“OP”) and underground

(“UG”) mining and milling operation, with industry-leading operating costs and high rate of return. The Study

outlines total gold production of 4.3 million gold ounces (“ Au oz”) over 12.3 years, resulting in an average

annual gold production profile of 350, 000 ounces with an All -In-Sustaining Cost (“ AISC”) per ounce of

$1,123. The Project after-tax net present value (“ NPV”) (5% discount rate) is $2.2 b illion with an after -tax

internal rate of return (“IRR”) of 27% at a gold price of $2,500 per ounce.

Final environmental permits are expected in Q2 -25, with a targeted construction decision in H2 -25. The

Project is ideally sequenced to leverage the strong macroeconomic conditions including a strong gold price,

lower inflation, and Guyana’s rapidly developing economy.

“The Oko West Feasibility Study marks a major milestone in realizing the value of what we consider one of the

world’s most exciting undeveloped gold projects. It confirms a long -life, high -margin operation with strong

economics, supported by a proven resource and solid infrastructure,” commented Louis-Pierre Gignac, President

& Chief Executive Officer. “With Tocantinzinho nearing nameplate capacity and generating meaningful free cash

flow, GMIN is well positioned to advance Oko West using the same experienced team and di sciplined execution

that delivered our first mine ahead of schedule and on budget. We remain committed to responsible development

and look forward to deepening our partnership with the Government of Guyana and local communities as we

advance Oko West as our second cornerstone asset.”

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Table 1: Oko West Feasibility Study Highlights

Description Units FS PEA Δ (%)

Production Data

OP Mill Feed Tonnage Mt 62 61 +2%

UG Mill Feed Tonnage Mt 14 15 (5%)

Total Mineralized Material Mined Mt 77 75 +2%

Total Waste Mined (OP and UG) Mt 429 367 +17%

Total Tonnage Mined (OP and UG) Mt 506 443 +14%

Strip Ratio waste: ore 6.8 6.0 +14%

Average Milling Throughput Mtpa 6.2 6.0 +3%

Average Milling Throughput tpd 16,911 16,110

Gold Head Grade g/t 1.89 2.00 (6%)

OP Head Grade g/t 1.57 1.72 (9%)

UG Head Grade g/t 3.26 3.19 +2%

Contained Gold koz 4,642 4,848 (4%)

Average Recovery % 93.5% 92.8% +1%

Total Gold Production koz 4,340 4,500 (4%)

Mine Life years 12.3 12.7 (3%)

Average Annual Gold Production oz 350,000 353,000 (1%)

Operating Costs (Average LOM)

Total Site Costs USD/oz $798 $728 +10%

Government Royalties (6.4%)* USD/oz $160 $126 +27%

Total Operating Cost* USD/oz $958 $853 +12%

All-In Sustaining Costs* USD/oz $1,123 $986 +14%

Capital Costs

Total Upfront Capital Cost USD M $972 $936 +4%

Initial UG Capital Costs (Sustaining Capital) USD M $68 $124 (45%)

OP and UG Sustaining Capital USD M $582 $413 +41%

Life of Mine Sustaining Capital USD M $650 $537 +21%

Closure Costs USD M $39 $37 +5%

Total Capital Costs USD M $1,661 $1,510 +10%

Financial Evaluation

Gold Price Assumption USD/oz $2,500 $1,950

After-Tax NPV5% USD M $2,163 $1,367

After-Tax IRR % 27% 21%

Payback Years 2.9 3.8

*Note: Assumes $2,500 per ounce base case gold price for calculating Government Royalty ($160 per ounce), which impacts Total

Operating Costs and AISC in FS evaluation. PEA assumed a $1,950 base case gold price for the calculation ($126 per ounce).

Government Royalty rate has not changed.

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Figure 1: Average Annual Gold Production and Operating Costs

Table 2: Sensitivity Analysis

Downside Base Upside

Scenario Case Case Case

Gold Price USD/oz $2,000 $2,500 $3,000

After Tax NPV5% USD M $1,155 $2,163 $3,169

Payback Years 4.4 Years 2.9 Years 2.1 Years

After-Tax IRR % 18% 27% 35%

Average Annual EBITDA USD M $375 $538 $702

Average Annual Free Cash Flow USD M $265 $388 $511

LOM EBITDA USD M $4,606 $6,622 $8,638

LOM Free Cash Flow USD M $3,253 $4,767 $6,281

Note: Average annual figures represent the 12.3-year operating period.

312 317 303 325 354 353 352 368 380

433

386

334

93

-

$200

$400

$600

$800

$1,000

$1,200

$1,400

-

100

200

300

400

500

600

700

Yr 1 Yr 2 Yr 3 Yr 4 Yr 5 Yr 6 Yr 7 Yr 8 Yr 9 Yr 10 Yr 11 Yr 12 Yr 13

Costs (USD/oz)

Production (koz Au)

Gold Recovered Total Cash Cost AISC

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Table 3: Sensitivity Analysis cont'd

After Tax Average Annual

Gold Price NPV5% IRR Payback EBITDA FCF

(USD/oz) (USD M) (%) (years) (USD M) (USD M)

$1,400 ($86) 4% 9.9 $178 $117

$1,600 $337 9% 7.6 $243 $166

$1,800 $748 14% 5.7 $309 $215

$2,000 $1,155 18% 4.4 $375 $265

$2,200 $1,558 22% 3.7 $440 $314

$2,400 $1,961 25% 3.1 $506 $363

$2,500 $2,163 27% 2.9 $538 $388

$2,600 $2,364 29% 2.7 $571 $412

$2,800 $2,767 32% 2.3 $637 $461

$3,000 $3,169 35% 2.1 $702 $511

$3,200 $3,571 38% 1.9 $768 $560

$3,400 $3,974 40% 1.7 $833 $609

$3,600 $4,376 43% 1.6 $899 $658

$3,800 $4,778 45% 1.5 $965 $708

$4,000 $5,181 48% 1.4 $1,030 $757

Note: Average annual figures represent the 12.3-year operating period.

FS Summary

The Corporation retained G Mining Services Inc. (“GMS ”) as lead consultants, along with other engineering

consultants, to complete the Study and prepare a technical report in compliance with National Instrument

43-101 Standards of Disclosure for Mineral Projects (“NI 43-101”).

The Study is derived using the Corporation’s mineral resource estimate effective as at September 15, 2024

(the “MRE”). The effective date of the FS is April 28, 2025, and a NI 43-101 compliant technical report will

be filed on the Corporation’s website and under its SEDAR+ profile within 45 days of this news release.

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Property Description, Location and Access

Guyana is a mining friendly country with active gold and bauxite mines. Oko West is an advanced-stage gold

development project , which straddles the Cuyuni -Mazaruni Mining Districts (administrative Region 7) in

north central Guyana, South America. The Project is located approximately 120 kilometres (“km”) southwest

of Georgetown, the capital city of Guyana and approximately 50 km west of Bartica, the capital city of

Region 7 (Figure 2). Bartica is a small town with approximately 17,000 people and is known as the gateway

to the country’s interior and its gold mining regions.

The Project can be accessed via numerous methods: helicopter direct from Ogle airport to the site, fixed -

wing plane from Ogle airport to Bartica airstrip, by car and then speedboat , or by four-wheel drive vehicle.

An air strip on site will be built to service the Project. From the town of Itabal li at the confluence of the

Cuyuni and Mazaruni rivers, one can use the Puruni or the Aremu laterite roads, using four- wheel drive

vehicles. Bartica is accessible by a 20 -minute direct flight from the Ogle airport in Georgetown or by road

and boat from Parika on the Essequibo River. There are regular boat services between Bartica and Parika.

The climate is equatorial and humid. The Project operated throughout the year without any interruptions

related to the weather. The total surface area of the property is 71 km2.

Figure 2: Project Location Map

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Updated Mineral Resource Estimate

Indicated mineral resources total 80.3 million tonnes (“Mt”) at an average gold grade of 2.10 grams per tonne

(“g/t Au”) for 5.4 million contained ounces of gold (“Moz Au”). Gold contained in the i ndicated category

represents 93% of the global resource. Inferred resources total 5.1 Mt at an average gold grade of 2.36 g/t

Au, for 0.4 Moz Au.

The MRE considers 544 diamond drill holes (including 39 wedged holes), 366 reverse circulation holes, and

59 trenches completed between December 2020 and September 2024. A total of 45,700m has been drilled

since the PEA for conversion of inferred mineral resources.

Approximately 90% of the inferred resources have been converted into indicated resources within the pit

and about 70% of the underground inferred mineral resources. The remaining underground material will be

drilled from underground. This high conversion rate increases confidence in the resource estimation.

Table 4: Mineral Resource Estimate

Category Tonnes

(Mt)

Gold Grade

(g/t Au)

Contained Gold

(koz)

Open Pit Resource

Indicated 73.0 2.00 4,689

Inferred 1.5 1.06 52

Underground Resource

Indicated 7.2 3.09 718

Inferred 3.6 2.93 337

Total Resource

Indicated 80.3 2.10 5,407

Inferred 5.1 2.36 390

These Mineral Resources are not Mineral Reserves as they have not demonstrated economic viability. All figures are rounded to reflect the relative

accuracy of the estimates. The Mineral Resources described above have been prepared in accordance with the Canadian Institute of Mining, Metallurgy

and Petroleum (“CIM”) Standards (2014) and follow Best Practices outlined by the CIM (2019). The qualified person for the est imate is Christian

Beaulieu, P. Geo. (OGQ#1072), Consulting geologist for GMS. The estimate has an effective date of September 15, 2024. The lower cut -offs used to

report open pit Mineral Resources, constrained by an open pit optimization shell, are 0.30 g/t Au in saprolite and alluvium/colluvium, 0.34 g/t Au in

transition, and 0.38 g/t Au in rock. Underground Mineral Resources are reported inside potentially mineable volume and include below cut-off material

(stope optimization cut-off grade of 1.35 g/t Au). The cut -off grades are based on a gold price of US$1,950 per troy ounce and show , 94.5%, 93.3%

and 93.9% processing recoveries for saprolite and alluvium/colluvium, transition and rock , respectively.

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Initial Mineral Reserve Estimate

The Project mine plan is based on Probable Mineral Reserves of 76.6 Mt at an average gold grade of 1.89

g/t Au for 4.64 Moz Au.

Table 5: Mineral Reserve Estimate

Category Tonnes

(Mt)

Gold Grade

(g/t Au)

Contained Gold

(koz)

Open Pit Reserves

Probable 62.4 1.57 3,156

Underground Reserves

Probable 14.2 3.26 1,486

Total Reserves

Probable 76.6 1.89 4,642

The Mineral Reserves were estimated using the Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Estimation of Mine ral Resources &

Mineral Reserves Best Practice Guidelines (Nov 29th, 2019) and CIM Definition Standards for Mineral Resources and R eserves, (May 10th, 2014).

The mine design and Mineral Reserve estimate have been completed to a level appropriate for feasibility studies. As such, the Mineral Reserves are

based on the Measured and Indicated Mineral Resources and do not include any Inferred Mineral Resources. The Inferred Mineral Resources contained

within the mine design are classified as waste. Mineral Reserves are estimated using a long -term gold price of 1,800 $/oz USD. The qualified person

for the estimate is Alexandre Burelle, P. E ng. (OIQ#5019855), Mine planning and financial analysis consultant. The estimate has an effective date of

April 2, 2025. Mineral Reserves for Open Pit are estimated at a cut -off grade of 0.41, 0.37, and 0.33 g/t Au for Rock , Transition, and Saprolite

respectively. The Open Pit Strip Ratio is 6.83:1 and Dilution factor is 14 %. Mineral Reserves for Underground Mine are estimated at a cu t-off grade

of 1.70 g/t Au. The underground mine dilution factor is 10% including 4% for the backfill. For the underground a minimum mining width of 5 m was

used. The numbers may not sum due to rounding; rounding followed the recommendations in NI 43 -101. The mine design and Mineral Reserve

estimate have been completed to a level appropriate for feasibility studies. The Mineral Reserve estimate stated herein is consistent with the CIM

definitions and is suitable for public reporting.

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Production Profile

The FS outlined an average annual gold production profile of 350,000 oz Au over the 12.3-year mine life.

Total gold production is 4.34 Moz Au with an average gold grade milled of 1.89 g/t Au, and an average

metallurgical recovery of 93.5%.

Figure 3: Gold Production Profile

During the initial three years of commercial production, the processing feed will solely be supplied by the

open pit. Starting in the fourth year of production, underground mining begins to contribute to processing

feed, and the UG operation is expected to achieve targeted production rates of 4,500 tonnes per day (“tpd”)

by the sixth year. Over the LOM, UG ore represents 32% of total gold recovered.

312 317 303 325 354 353 352 368 380

433

386

334

93

1.54 1.49 1.50

1.80

1.96 1.96 1.95 2.03 2.03

2.40

2.14 2.04

1.78

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0.50

1.00

1.50

2.00

2.50

3.00

-

100

200

300

400

500

600

Yr 1 Yr 2 Yr 3 Yr 4 Yr 5 Yr 6 Yr 7 Yr 8 Yr 9 Yr 10 Yr 11 Yr 12 Yr 13

Grade Milled (g/t Au)

Gold Recovered (koz Au)

Gold Recovered Grade Milled