10 Lamgold Reports Mineral Resources and Reserves
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lAMGOLD REPORTS MINERAL RESOURCES AND RESERVES
FOR THE YEAR ENDED 2025
All amounts are in US dollars, unless otherwise indicated.
Measured and indicated resources are quoted inclusive of proven and probable reserves for all sites
Toronto, Ontario, February 17, 202 6 – IAMGOLD Corporation (NYSE:IAG) (TSX:IMG) (“IAMGOLD” or the
“Company”) announces its updated Mineral Resources and Mineral Reserves statement as of December 31, 2025
prepared in accordance with National Instrument 43 -101 – Standards of Disclosure for Mineral Projects (“NI 43-
101”). A summary table of the Company’s Mineral Resources and Mineral Reserves, including attributable ounces
accounting for ownership interest, can be found at the end of this news release.
Highlights
• Proven and Probable (“P&P”) Mineral Reserves (100% basis) total 9.9 million ounces of gold in 279.6 Mt
at 1.10 g/t Au (7.5 million ounces attributable). P&P Mineral Reserves decreased 7%, or 796,000 ounces,
from the year prior, primarily due to depletion at Côté Gold and Essakane partially offset by an increase in
Mineral Reserves at Westwood.
• Measured and Indicated (“M&I”) Mineral Resources (100% basis) increased 16% to 31.0 million ounces of
gold in 1.0 Bt at 0.94 g/t Au (24.6 million ounces attributable). The increase was primarily associated with
the conversion of Inferred Mineral Resources in the Gosselin deposit at Côté Gold and Nelligan deposit,
coupled with the inclusion of the Philibert and Chevrier deposits as part of the Northern Superior transaction
towards the end of the year.
▪ Côté Gold (Côté and Gosselin) M&I Mineral Resources, inclusive of Mineral Reserves and on a
100% basis, increased 12%, or approximately 2.0 million ounces, to an estimated 18.2 million
ounces (12.7 million ounces attributable) as of December 31, 2025. Infe rred Mineral Resources
decreased approximately 2.0 million ounces to 2.2 million ounces.
▪ Essakane M&I Mineral Resources (excluding Gossey) , inclusive of Mineral Reserves and on a
100% basis, increased 11% to an estimated 4.4 million ounces (3.8 million ounces attributable) as
of December 31, 2025, with a 50% increase in tonnes (to 150 Mt) offsetting a 26% decrease in
grades (to 0.91 g/t Au, including stockpiles). The increase in tonnes and ounces underscores
confidence in the potential for Essakane to extend its mine life within the fence beyond current
guidance.
▪ Westwood M&I Mineral Resources, inclusive of Mineral Reserves, increased 682,000 ounces to
2.4 million ounces as of December 31, 2025, with a 79% increase in tonnes (to 11.9 Mt) offsetting
a 22% decrease in average grade to 6.24 g/t Au.
• Inferred Mineral Resources (100% basis) decreased 2% t o 12. 5 million ounces ( 11.3 million ounces
attributable).
• Gold price assumptions for Mineral Reserves were updated to $2,000 per ounce for Westwood (including
Grand Duc) and Essakane; and $1,700 per ounce for Côté Gold. 2025 Mineral Resources were updated
using a gold price of: $2,500 per ounce for Essakane, Westwood (incl. Grand Duc), Nelligan, Monster Lake
and Gossey; and $2,100/oz for Côté.
“I want to congratulate our exploration teams for their continued success in expanding our resource base.
IAMGOLD today has 31 million ounces in Measured and Indicated Resources along with an additional 12.5 million
ounces of Inferred Mineral Resources, positioning the company among the largest endowments of gold resources
among mid-tier gold producers,” said Renaud Adams, President and Chief Executive Officer of IAMGOLD. “Further,
approximately 80% of our Measured and Indicated ounces and 90% of global Inferred ounces are located in
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Canada – reinforcing IAMGOLD as a leading Canadian, modern multi-asset mid-tier gold producer with significant
growth potential.”
“As we look at our operations, all eyes this year will be on Côté Gold, as our exploration and site teams are working
tirelessly towards the technical report to be delivered in the fourth quarter which will outline a mine plan
incorporating a plant expansion that will leverage a larger subset of ounces from the combined Côté and Gosselin
pits. At Westwood, exploration activities will be conducted to support the study of options to expand the mine in
the eastern parts of Westwood underground that could be potentially amenable to bulk mining. Additional
extensions to the Grand Duc pit will also be investigated this year. At Essakane, the Mineral Resource tonnes
increased 50% building confidence in the potential for the project to see a mine life extension beyond the current
mine plan.”
“It is going to be an exciting year at our Nelligan Mining Complex in the Chibougamau-Chapais region of Quebec,
as we build on our acquisitions at the end of last year of Northern Superior and Orbec, which significantly increased
our property package and the potential of the consolidated camp. This year we are substantially increasing our
budget to $ 24 million for a comprehensive exploration program. The Nelligan Mining Complex already has a
significant mineral inventory of over 4.3 million Measured and Indicated ounces and 7.5 million Inferred ounces ,
positioning the project among the largest pre-production stage gold projects in Canada. The exploration program
this year will look to expand the mineralized footprint of both Nelligan and Philibert, while testing Monster Lake at
depth, and then conducting regional exploration on high priority targets to further grow the potential of the project."
Mineral Reserves
TABLE 1: MINERAL RESERVES (@100%) SUMMARY1
20242 20253 %▲
Tonnes Grade Ounces Tonnes Grade Ounces Tonnes Grade Ounces
(000s) (g/t) (000s) (000s) (g/t) (000s) (000s) (g/t) (000s)
Côté Gold3,4
Proven 127,747 1.07 4,376 116,055 1.05 3,902 -9% -2% -11%
Probable 101,427 0.91 2,965 101,112 0.97 3,139 0% 6% 6%
Total 229,175 1.00 7,341 217,167 1.01 7,041 -5% 1% -4%
Westwood3,5
Proven (underground) 717 12.61 291 897 10.89 314 25% -14% 8%
Probable (underground) 1,886 10.98 666 2,565 9.30 767 36% -15% 15%
Subtotal 2,603 11.43 957 3,462 9.72 1,082 33% -15% 13%
Proven (Grand Duc) 363 0.80 9 658 0.81 17 81% 2% 85%
Probable (Grand Duc) 1,090 1.08 38 1,238 1.25 50 14% 16% 31%
Subtotal 1,453 1.01 47 1,896 1.10 67 30% 9% 42%
Total 4,056 7.70 1,004 5,358 6.67 1,148 32% -13% 14%
Essakane3,6
Proven (stockpile) 18,876 0.65 396 22,178 0.64 457 17% -2% 15%
Probable (open pit) 44,017 1.36 1,920 34,903 1.09 1,219 -21% -20% -36%
Total 62,893 1.15 2,316 57,081 0.91 1,676 -9% -20% -28%
Total P&P Reserves 296,124 1.12 10,661 279,606 1.10 9,865 -6% -2% -7%
1. Figures may not add due to rounding.
2. 2024 Mineral Reserves estimated as of December 31, 2024, using a gold price of $1,500 per ounce for Essakane and Westwood underground, $1,800/oz
for Grand Duc, and $1,400/oz for Cote Gold.
3. 2025 Mineral Reserves estimated as of December 31, 202 5, using a gold price of $ 2,000/oz for Westwood (including Grand Duc) and Essakane; and
$1,700/oz for Côté Gold.
4. Côté Gold Mineral Reserves as of December 31, 2025 were estimated using a 0.46 g/t Au cut -off grade, up from 0.35 g/t Au at year end 2024.
5. Westwood (underground) Mineral Reserves as of December 31, 2025 were estimated using a 6.40 g/t Au cut-off grade, down from 6.82 g/t at year end
2024; Grand Duc Mineral Reserves as of December 31, 2025 were estimated using a 0.59 g/t cut-off grade, up from 0.54 g/t at year end 2024.
6. Essakane Mineral Reserves as of December 31, 2025 were estimated using a cut -off grade range of 0.31 –0.44 g/t Au, down from of 0.39 –0.55 g/t Au
at year end 2024.
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Proven and Probable Mineral Reserves, on a 100% basis for current assets, were estimated at 9.9 million ounces
of gold (7.5 million ounces attributable) as of December 31, 202 5, which was a 7% decrease or 796,000 ounces,
from the year prior. At Côté Gold, Mineral Reserves decreased 301,000 ounces from the prior year period as
updated estimates partially offset depletion (based on 10.9 Mt at 1.22 g/t for contained ounces of 428,100 ounces
at 100% interest). The Côté Gold Mineral Reserve block model will be updated this year resulting in an updated
mine plan incorporating both Côté and Gosselin. At Westwood, Mineral Reserves from the underground increased
125,000 ounces and 20,000 ounces from the Grand Duc open pit, more than offsetting depletion , primarily as a
result of the change in resource model and increased gold price assumption and reduction in the underground cut-
off grade to 6.40 g/t Au (down from 6.82 g/t Au previously) . At Essakane, Mineral Reserves decreased 640,000
ounces, primarily due to depletion (428,000 contained ounces milled) and geology model adjustments as mining
activities continue to progress through the mine plan.
Mineral Resources
Measured and Indicated (“M&I”) Mineral Resources, inclusive of Mineral Reserves and on a 100% basis, for
IAMGOLD’s assets increased 16% or 4.3 million ounces, for a total of 31.0 million ounces as of December 31,
2025 (24.6 million ounces attributable). The increase was primarily associated with the upgrading of Mineral
Resources at Côté Gold, Westwood and Nelligan, coupled with the acquisition of the Philibert and Chevrier deposits
as part of the Northern Superior transaction towards the end of the year. Global Inferred Mineral Resources (on a
100% basis) decreased 2%, or 0.3 million ounces, to a total of 12.5 million ounces as of December 31, 2025 (11.3
million ounces attributable). Note that Inferred Mineral Resources have a great amount of uncertainty as to their
grade and quantity because they are based on limited geological evidence. It cannot be assumed that all or part of
the Inferred Mineral Resources will ever be upgraded to a higher category or converted to Mineral Reserves.
The Company assumed a gold price of $ 2,500 per ounce for estimating Mineral Resources as of December 31,
2025 at Essakane, Westwood Complex, Gosselin, Nelligan and Monster Lake. This was an increase from the year
prior in which these operations assumed a gold price of $1,800 per ounce (except Gosselin which was at $1,700
per ounce) in the Mineral Resources estimate. The gold price assumption for Côté Gold was $2,100 per ounce, up
from $1,700 per ounce previously.
Côté & Gosselin
Côté Gold (Côté and Gosselin) M&I Mineral Resources, inclusive of Mineral Reserves and on a 100% basis,
increased 12%, or approximately 2.0 million ounces, to an estimated 18.2 million ounces (12.7 million ounces
attributable) as of December 31, 2025. Inferred Mineral Resources decreased approximately 2.0 million ounces to
2.2 million ounces.
The 2025 drilling plan at Côté and Gosselin prioritized increasing the confidence in the existing resource and
converting a large part of the Inferred Resource to the Indicated Resource category. The program was increased
to approximately 53,750 metres for the year at Gosselin. The results of the Gosselin drilling program will inform the
planned updated technical report which will consider a larger scale Côté Gold Mine with a mine plan targeting both
the Côté and Gosselin zones over the life of mine. This updated technical repor t is expected to be completed by
the end of 2026.
Essakane
Essakane M&I Mineral Resources, inclusive of Mineral Reserves on a 100% basis (excluding Gossey), increased
11% to an estimated 4.4 million ounces (3.8 million ounces attributable) as of December 31, 2025, with a 50%
increase in tonnes (to 150 Mt) offsetting a 26% decrease in grades (to 0.91 g/t Au, including stockpiles). The
increase in tonnes and ounces underscores confidence in the potential for Essakane to extend its mine life within
the fence beyond current guidance (last year Essakane processed 12.6 M t of ore at an average head grade of
1.18 g/t Au). Inferred Mineral Resources (excluding Gossey) increased 20% from the year prior to an estimated
853,000 ounces at 1.10 g/t Au.
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TABLE 2: MINERAL RESOURCES SUMMARY (100%, incl. of Mineral Reserves)1
20242 20253 %▲
Tonnes Grade Ounces Tonnes Grade Ounces Tonnes Grade Ounces
(000s) (g/t) (000s) (000s) (g/t) (000s) (000s) (g/t) (000s)
Côté Gold4
Côté4
Measured 162,140 0.94 4,907 153,873 0.93 4,598 -5% -1% -6%
Indicated 276,404 0.77 6,878 268,833 0.77 6,697 -3% 0% -3%
Total M&I 438,545 0.84 11,785 422,707 0.83 11,295 -4% -1% -4%
Inferred 60,362 0.61 1,177 62,760 0.60 1,206 4% -2% 2%
Gosselin4
Indicated 161,300 0.85 4,420 266,741 0.80 6,861 65% -6% 55%
Inferred 123,900 0.75 2,980 37,840 0.79 959 -69% 5% -68%
Total M&I 599,845 0.84 16,205 689,447 0.82 18,156 15% -3% 12%
Total Inferred 184,262 0.70 4,157 100,600 0.67 2,165 -45% -5% -48%
Westwood5
Measured 1,062 9.15 312 1,619 7.21 375 52% -21% 20%
Indicated 5,627 7.75 1,402 10,324 6.09 2,022 83% -21% 44%
Total M&I 6,689 7.97 1,715 11,943 6.24 2,397 79% -22% 40%
Inferred 4,369 12.82 1,801 4,507 10.46 1,515 3% -18% -16%
Essakane
Measured 21,157 0.64 433 38,312 0.52 640 81% -18% 48%
Indicated 78,722 1.40 3,534 111,683 1.05 3,772 42% -25% 7%
Total M&I 99,879 1.24 3,967 149,995 0.91 4,412 50% -26% 11%
Inferred 12,623 1.76 713 24,195 1.10 853 92% -38% 20%
Gossey
Indicated 8,383 0.87 235 14,795 0.75 355 76% -14% 51%
Inferred 1,611 1.00 52 2,688 0.85 74 67% -15% 42%
Total M&I 108,262 1.21 4,402 164,790 0.90 4,767 52% -25% 13%
Total Inferred 14,234 1.67 765 26,883 1.07 927 89% -36% 21%
Nelligan Mining Complex7
Nelligan
Indicated 102,845 0.95 3,125 122,000 0.95 3,700 19% 0% 18%
Inferred 166,395 0.96 5,161 151,000 0.96 4,647 -9% -1% -10%
Monster Lake
Indicated 239 10.93 84 243 13.04 102 - - -
Inferred 1,053 14.44 489 1,046 14.83 499 -1% 3% 2%
Philibert6
Indicated 0 0.00 0 7,884 1.10 279 N/A N/A N/A
Inferred 0 0.00 0 48,465 1.10 1709 N/A N/A N/A
Chevrier6
Indicated 0 0.00 0 6,400 1.26 260 N/A N/A N/A
Inferred 0 0.00 0 15,660 1.30 652 N/A N/A N/A
Total M&I 103,084 0.97 3,209 136,527 0.99 4,341 32% 2% 35%
Total Inferred 167,448 1.05 5,650 216,171 1.08 7,507 29% 3% 33%
Diakha-Siribaya5
Indicated 27,937 1.48 1,325 27,937 1.48 1,325 0% 0% 0%
Inferred 8,468 1.53 417 8,468 1.53 417 0% 0% 0%
Total M&I
Resources1 845,817 0.98 26,656 1,030,644 0.94 30,987 22% -5% 16%
Total Inferred
Resources1 378,782 1.05 12,791 356,628 1.09 12,530 -6% 4% -2%
1. Figures may not add due to rounding.
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2. 2024 Mineral Resources estimated as of December 31, 2024, using a gold price of : $1,800 per ounce for Essakane, Westwood (incl. Grand Duc),
Nelligan, Monster Lake and Gossey; and $1,700/oz for Côté and Gosselin.
3. 2025 Mineral Resources estimated as of December 31, 2025, using a gold price of: $2,500 per ounce for Essakane, Westwood (inc l. Grand Duc),
Nelligan, Monster Lake and Gossey; $2,100/oz for Côté Gold, $1800/oz for Chevrier, $1747/oz for Philibert.
4. Côté Gold and Gosselin block models were adjusted for price and drilling data up to September 29, 2025. Drilling resumed at Côté through the year
with the full data set to be incorporated into an updated Mineral Resources estimate to inform the Q4 2026 updated mine plan.
5. Diakha-Siribaya Mineral Resources are unchanged from the prior year, with an unchanged gold price of $1,500 per ounce. The definitiv e agreement
to sell the Diakha -Siribaya Gold Project in Mali to Managem S.A. expired on December 31, 2024, and was not exten ded. The Company is pursuing
alternative options for the sale of this asset.
6. Philibert and Chevrier were acquired with the closing of the Northern Superior transaction in December 2025. The prior Minera l Resources estimates
for these assets are based on data as reported in the respective NI 43 -101 Technical Reports . Philibert and Chevrier Mineral Resources (including
underground Inferred Resources) are estimated as of December 31, 2025, using a gold price of $1,747 and $1,800 per ounce respectively.
7. At the time of the Northern Superior acquisition, disclosed estimates were 3.75 Moz Au Measured and Indicated Mineral Resourc es and 8.65 Moz Au
Inferred Mineral Resources, which included Croteau. The Company opted to exclude the mineral resources previously associated with the Croteau
property in its year -end update, resulting in reported totals of 4.34 Moz Au Measured and Indicated Mineral Resources and 7. 50 Moz Au Inferred
Mineral Resources.
Westwood
Westwood M&I Mineral Resources, inclusive of Mineral Reserves, increased 682,000 ounces to 2.4 million ounces
as of December 31, 2025, with a 79% increase in tonnes (to 11.9 Mt) offsetting a 22% decrease in average grade
to 6.24 g/t Au . Inferred Mineral Resources decreased 16%, or 286,000 ounces to 1. 5 million ounces with an
average grade of 10.5 g/t Au.
Nelligan Mining Complex
The Nelligan Mining Complex, situated in the Chibougamau–Chapais region of central Quebec, encompasses the
Nelligan, Philibert, Chevrier, and Monster Lake deposits. The Philibert and Chevrier deposits were added to the
portfolio following the completion of the Northern Superior transaction in December 2025.
On a consolidated basis, the Nelligan Mining Compl ex reported a significant increase in Indicated and Inferred
Mineral Resources. Indicated Resources increased 1.1 million ounces to a total of 4.3 million ounces at an average
grade of 0.99 g/t Au. Inferred ounces increased 1. 9 million ounces to a total of 7.5 million ounces at an average
grade of 1.08 g/t Au. The Nelligan deposit reported an increase of 575,000 ounces in Indicated Mineral Resources,
to a total of 3.7 million ounces at an average grade of 0.9 5 g/t. The increase was primarily a result of the in fill
program conducted last year to increase the confidence in ounces from Inferred Mineral Resources.
This year, IAMGOLD has outlined a budget of approximately $24 million for exploration activities within the Nelligan
Mining Complex. The goal of the program will be to conduct thorough testing of Philibert, expand Nelligan and
continue to test Monster Lake at depth all in support of a conceptual preliminary economic assessment in 2027.
Further, the Company is eager to test high priority targets within the region.
TABLE 3: MINERAL RESOURCES AND MINERAL RESERVES AS OF DECEMBER 31, 20251,2,3,4,5,6,7,8
Mineral Resources are inclusive of Mineral Reserves
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Tonnes Grade Ounces Attributable
Ounces
(000s) (g/t Au) (000s) (000s)
Côté Gold, Canada 70%
Côté
Proven Mineral Reserves 116,055 1.05 3,902 2,731
Probable Mineral Reserves 101,112 0.97 3,139 2,197
Subtotal P&P 217,167 1.01 7,041 4,929
Measured Mineral Resources 153,873 0.93 4,598 3,219
Indicated Mineral Resources 268,833 0.77 6,697 4,688
Subtotal M&I (incl. of Reserves) 422,707 0.83 11,295 7,907
Inferred Mineral Resources 62,760 0.60 1,206 844
Gosselin
Indicated Mineral Resources 266,741 0.80 6,861 4,803
Inferred Mineral Resources 37,840 0.79 959 671
Total M&I 689,447 0.82 18,156 12,709
Total Inferred 100,600 0.67 2,165 1,515
Westwood, Canada 100%
Proven Mineral Reserves 1,555 6.63 331 331
Probable Mineral Reserves 3,803 6.68 817 817
Subtotal P&P 5,358 6.67 1,148 1,148
Measured Mineral Resources 1,619 7.21 375 375
Indicated Mineral Resources 10,324 6.09 2,022 2,022
Subtotal M&I (incl. of Reserves) 11,943 6.24 2,397 2,397
Inferred Mineral Resources 4,507 10.46 1,515 1,515
Essakane, Burkina Faso 85%
Proven Mineral Reserves 22,178 0.64 457 388
Probable Mineral Reserves 34,903 1.09 1,219 1,036
Subtotal P&P 57,081 0.91 1,676 1,425
Measured Mineral Resources 38,312 0.52 640 544
Indicated Mineral Resources 111,683 1.05 3,772 3,207
Subtotal M&I (incl. of Reserves) 149,995 0.91 4,412 3,750
Inferred Mineral Resources 24,195 1.10 853 725
Gossey
Indicated Mineral Resources 14,795 0.75 355 302
Inferred Mineral Resources 2,688 0.85 74 63
Total M&I 164,790 0.90 4,767 4,052
Total Inferred 26,883 1.07 927 788
Nelligan Mining Complex8, Canada 100%
Nelligan
Indicated Mineral Resources 122,000 0.95 3,700 3,700
Inferred Mineral Resources 151,000 0.96 4,647 4,647
Monster Lake
Indicated Mineral Resources 243 13.04 102 102
Inferred Mineral Resources 1,046 14.83 499 499
Philibert7 (75%7)
Indicated Mineral Resources 7,884 1.10 279 209
Inferred Mineral Resources 48,465 1.10 1,709 1,282
Chevrier7
Indicated Mineral Resources 6,400 1.26 260 260
Inferred Mineral Resources 15,660 1.30 652 652
Total M&I 136,527 0.99 4,341 4,271
Total Inferred 216,171 1.08 7,507 7,079
Diakha-Siribaya, Mali6 90%
Indicated Mineral Resources 27,937 1.48 1,325 1,193
Inferred Mineral Resources 8,468 1.53 417 376
Total Proven & Probable Mineral Reserves 279,606 1.10 9,865 7,502
Total Measured & Indicated Mineral Resources 1,030,644 0.94 30,987 24,622
Total Inferred Mineral Resources 356,628 1.09 12,530 11,273
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1. Figures may not add due to rounding.
2. In mining operations, Measured Mineral Resources and Indicated Mineral Resources that are not Mineral Reserves are considered uneconomic at the
price used for Mineral Reserves estimations but are deemed to have a reasonable prospect of economic extraction.
3. See “Cautionary Note to U.S. Investors Regarding Disclosure of Mineral Reserve s and Mineral Resources Estimates”.
4. 2025 Mineral Reserves estimated as of December 31, 2025, using a gold price of $2,000 per ounce for Westwood (including Grand Duc) and Essakane;
and $1,700 per ounce for Côté Gold.
5. 2025 Mineral Resources estimated as of December 31, 2025, using a gold price of: $2,500 per ounce for Essakane, Westwood (incl. Grand Duc), Nelligan,
Monster Lake and Gossey; and $2,100/oz for Côté.
6. Diakha-Siribaya Mineral Resources are estimated at a gold price of $1,500 per ounce. The definitive agreement to sell the Diakha -Siribaya Gold Project
in Mali to Managem S.A. expired on December 31, 2024, and was not extended. The Company is pursuing alternative options for the sale of this asset.
7. Philibert (75% with option to acquire 100% from SOQUEM for C$3.5M) and Chevrier were acquired with the closing of the Northern Superior transaction
in December 2025. The Mineral Resources estimates for these assets are based on data as reported in the respective NI 43 -101 Technical Reports.
Chevrier Mineral Resources (including underground Inferred Resources) have been estimated as of September 23, 2022 using a $1,800/oz gold price
and have been estimated in accordance with NI 43-101. Philibert Mineral Resources have been estimated as of September 22, 2023 using a $1,747/oz
gold price and have been estimated in accordance with NI 43-101.
8. At the time of the Northern Superior acquisition, disclosed estimates were 3.75 Moz Au Measured and Indicated Mineral Resources and 8.65 Moz Au
Inferred Mineral Resources, which included Croteau. The Company opted to exclude the mineral resources previously associated with the Croteau
property in its year -end update, resulting in reported totals of 4.34 Moz Au Measured and Indicated Mineral Resources and 7.50 Moz Au Inferred
Mineral Resources.
Qualified Person and Technical Information
Christine Beausoleil, P.Geo., Senior Director, Mining Geology, IAMGOLD Corporation is the “qualified person” for
the purposes of NI 43 -101 (“QP”) with respect to the mineralization being reported on and is responsible for the
review and approval of all Mineral Resources estimates for IAMGOLD. Adrienne Rispoli, P.Eng., Senior Director,
Mining & Integrated Planning, IAMGOLD Corporation is the QP for the purposes of NI 43 -101 with respect to the
mineralization being reported on and is responsible for the review an d approval of all Mineral Reserves estimates
for IAMGOLD.
For the recently acquired Philibert and Chevrier properties (acquired on December 19, 2025), the mineral resource
estimates provided in this statement are based on data as reported in the respective NI 43-101 Technical Reports.
The “qualified persons” resp onsible for these estimates have consented under NI 43 -101 to the incorporation of
their data into this news release. IAMGOLD has not revised or altered the original information provided for these
properties.
The Company’s Mineral reserves are comprised of in -place material, i.e. material containing ounces of gold for
which an assessment of key modifying factors such as mining, processing, metallurgical recovery, infrastructure,
economic, legal, environmental, social and government al factors are used to determine their economic viability.
Mineral Reserves are estimated with a mill feed reference point.
In estimating Mineral Reserves, cut-off grades are established using the Company’s long-term metal price
and foreign exchange assumptions, royalties, the mining dilution & metallurgical recovery factors and
estimated production costs over the life of the related operation. As part of the annual Mineral Reserve
estimation process, the cost models used for cut-off grade calculations are compared to prior estimates and
are updated appropriately based on actual operating performance and projections. Cut-off grades are
determined by corporate objectives, mining method as well as considering the various mine -mill-tailing
capacities specific to each operation.
There are numerous parameters inherent in estimating Proven Mineral Reserves and Probable Mineral Reserves,
including many factors beyond the Company’s control. The estimation of Mineral Reserves is a subjective process,
and the accuracy of any Mineral Reserves estimate is a function of the quality of available data and of engineering
and geological interpretation and judgment. Results from drilling, testing and production, as well as material
changes in metal prices subsequent to the date of an estimate, may justify a revision of such estimates. The nature
of mining activities is such that the extraction of ore from a mine reduces Mineral Reserves. In order to renew
Mineral Reserves (at least partially) on most of its producing properties, the Company carries out exploration drilling
programs at depth and laterally.
For each of the projects and properties it operates, the Company has established rigorous methods and procedures
aimed at assuring reliable estimates of its Mineral Resources and Reserves. For each mine and project, the
relevant QPs verified the data incorporated, including sampling, analytical and test data underlying the information
contained in this news release. Quality control falls under the responsibility of Ms. Beausoleil and Ms. Rispoli.
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About IAMGOLD
IAMGOLD is an intermediate gold producer and developer based in Canada with operating mines in North America
and West Africa, including Côté Gold (Canada), Westwood (Canada) and Essakane (Burkina Faso). The Côté
Gold Mine is among the largest gold mines in production in Canada, which IAMGOLD operates in a 70|30
partnership with Sumitomo Metal Mining Co. Ltd. (“SMM”). In addition, the Company has an established portfolio
of early stage and advanced exploration projects withi n high potential mining districts, including the large -scale
Nelligan Mining Complex located in Quebec, Canada. IAMGOLD employs approximately 3,700 people and is
committed to maintaining its culture of accountable mining through high standards of Environmental, Social and
Governance practices. IAMGOLD is listed on the New York Stock Exchange (NYSE:IAG) and the Toron to Stock
Exchange (TSX:IMG).
IAMGOLD Contact Information
Graeme Jennings, Vice President, Investor Relations
Tel: 416 360 4743 | Mobile: 416 388 6883
Toll-free: 1 888 464 9999
CAUTIONARY NOTE TO U.S. INVESTORS REGARDING DISCLOSURE OF MINERAL RESERVES AND MINERAL RESOURCES
ESTIMATES
The mineral Resources and Reserves estimates contained in this news release have been prepared in accordance with NI 43-101 and
the Canadian Institute of Mining, Metallurgy and Petroleum (“CIM”) – CIM Definition Standards on Mineral Resources and Mineral
Reserves, adopted by the CIM Council, as amended (the “CIM Standards”). These standards are similar to those found in subpart 1300
of Regulation S-K, used by the United States Securities and Exchange Commission (the “SEC”). However, the definitions in NI 43-101
and the CIM Standards differ in certain respects from those under subpart 1300 of Regulation S-K . Accordingly, mineral Resources and
Reserves information contained in this news release may not be comparable to similar information disclosed by United States
companies.
As a result of the adoption of subpart 1300 of Regulation S-K (the “SEC Modernization Rules”), which more closely align its disclosure
requirements and policies for mining properties with current industry and global regulatory practices and standards, including NI 43-101
and the CIM Standards, and which became effective on February 25, 2019, the SEC now recognizes estimates of "measured mineral
resources", "indicated mineral resources" and "inferred mineral resources." In addition, the SEC has amended defin itions of "proven
mineral reserves" and "probable mineral reserves" in its amended rules, with definitions that are substantially similar to those used in NI
43-101 and the CIM Standards. Issuers must begin to comply with the SEC Modernization Rules in their first fiscal year beginning on or
after January 1, 2022, though Canadian issuers that report in the United States using the Multijurisdictional Disclosure System ("MJDS")
may still use NI 43-101 rather than the SEC Modernization Rules when using the SEC's MJDS registration statement and annual report
forms.
United States investors are cautioned that while the SEC now recognizes "measured mineral resources", "indicated mineral resources"
and "inferred mineral resources" under the SEC Modernization Rules, investors should not assume that any part or all of the mineral
deposits in these categories will ever be converted into a higher category of mineral resources or into mineral reserves. The se terms
have a great amount of uncertainty as to their economic and legal feasibility. Under Canadian regulations, estimates of inferred mineral
resources may not form the basis of feasibility or pre-feasibility studies, except in limited circumstances.
Investors are cautioned not to assume that any "measured mineral resources", "indicated mineral resources", or "inferred mine ral
resources" that the Company reports in this news release are or will be economically or legally mineable. Further, "inferred mineral
resources" have a great amount of uncertainty as to their existence and as to their economic and legal feasibility. It cannot be assumed
that any part or all of an inferred mineral Resources will ever be upgraded to a higher category.
The mineral Reserves and mineral Resources data set out in this news release are estimates, and no assurance can be given that the
anticipated tonnages and grades will be achieved or that the indicated level of recovery will be realized.