Osisko Metals Announces Significant Increase in Mineral Resources at Gaspé Copper Base Case Outlines M&I Resources of 1.83 Billion tonnes at 0.27% Cu and Inferred Resources of 0.24 Billion tonnes at 0.41% Cu 2026 Drill Program to Commence at Month End to Further Infill and Expand Resource
Osisko Metals Announces Significant Increase in Mineral Resources at Gaspé
Copper
Base Case Outlines M&I Resources of 1.83 Billion tonnes at 0.27% Cu and Inferred Resources of 0.24 Billion tonnes at
0.41% Cu
2026 Drill Program to Commence at Month End to Further Infill and Expand Resource
DPEX Drill Program to Commence in May
MONTREAL, April 14, 2026 -- Osisko Metals Incorporated (the “ Company” or “Osisko Metals”) (TSX: OM; OTCQX: OMZNF)
is pleased to announce an updated Mineral Resource Estimate (“ MRE”) for the Gaspé Copper Project, located in Eastern
Quebec, following 118,000 metres of drilling completed in 2025.
The updated MRE (Table 1) includes base case, pit-constrained resources comprising 1,834 million tonnes averaging
0.27% Cu (0.32% CuEq) of Measured and Indicated categories (M&I), and 239 million tonnes averaging 0.41% Cu (0.46%
CuEq) of Inferred category. The updated M&I Resource represents a 119% increase in copper metal content over the
previously reported Indicated Resource ( see November 14, 2024 news release ). This pit-constrained M&I Resource
outlines one of the largest undeveloped copper-molybdenum deposits in North America :10.8 billion pounds (4.88
million tonnes) of contained copper , as well as significant molybdenum (673 million pounds), and silver (93 million ounces).
Inferred resources outline the potential for an additional 2.2 billion pounds (0.98 million tonnes) of contained copper, 83 million
pounds of molybdenum, and 14 million ounces of silver.
Osisko Metals Chief Executive Officer Robert Wares commented: “We are very proud to announce this updated mineral
resource estimate for Gaspé Copper. The 2025 drill program successfully converted and expanded the 2024 MRE to the
Measured and Indicated resource categories and has added new significant higher-grade Inferred resources to the south. An
additional 50,000 metre drill program will commence at the end of this month, with the objective of upgrading the remaining
Inferred Resource to the Indicated category and expanding the boundaries of the deposit to the southwest towards the former
Needle Mountain open pit. Additionally, the Deep Porphyry Exploration (DPEX) program will be testing the depths of the
Porphyry Mountain deposit, in preparation for an Inferred MRE on that deposit to be included in the next MRE update on
Gaspé Copper. With additional drilling, there is also excellent potential for conversion of currently categorized in-pit waste rock
to mineralized material in the direction of Needle Mountain. The planned 2026 drill programs present a strong opportunity for
continued resource growth of the overall Gaspé Copper project.”
Mr. Wares continued: “Gaspé Copper demonstrates all the characteristics of a potential generational mine, as a major
Canadian copper development project located in one of the world’s safest mining jurisdictions. This deposit may once again
become the main economic driver for the Gaspé Peninsula for decades to come. This important asset has the potential to
become a core component of Québec’s critical mineral development strategy that aims to provide essential metals for
advanced technologies and global decarbonization initiatives.”
Table 1: MRE Base Case at CuEq = 0.16% cut-off. See Table 2 for broader range of sensitivities.
Category
Cut-off Cut-off Tonnes CuEq Cu Mo Ag Cu Cu Mo Mo Ag
CuEq
%1 NSR2 Mt % % % g/t M lbs kt M lbs kt Moz
Measured 0.16 $11.71 136.5 0.42 0.37 0.014 1.98 1,128 512 41.9 19.0 8.7
Indicated 0.16 $11.71 1,697.7 0.32 0.26 0.017 1.54 9,639 4373 631.3 286.4 84.1
M&I 0.16 $11.71 1,834.2 0.32 0.27 0.017 1.57 10,766 4,883 673.2 305.4 92.8
Inferred 0.16 $11.71 238.8 0.46 0.41 0.016 1.88 2,158 979 82.9 37.6 14.5
1. Copper Equivalent (CuEq) grades are presented for illustrative purposes only to express the combined value of copper,
molybdenum, and silver as a single copper grade. CuEq grades are calculated using long-term metal prices of
US$4.50/lb copper, US$20.00/lb molybdenum, and US$45.00/oz silver, and incorporate assumptions for metallurgical
recoveries, payable metal factors, smelting and refining charges, transportation costs, and royalties. Hence the CuEq
calculation is essentially based on net smelter return (NSR) values. NSR for each metal is estimated by applying
metallurgical recoveries, payable factors, metal prices, and applicable smelting, refining, transportation, and penalty
charges to the in-situ metal grades. CuEq grades are derived using a linear regression relationship established between
copper grade and copper NSR, expressed as:
Cu Grade (%) = (1.4669 + NSR_Cu) / 8235.6
Copper equivalent grade is then calculated by substituting total NSR (Cu + Mo + Ag) for copper NSR in the regression
equation, as follows:
CuEq Grade (%) = (1.4669 + NSR_Cu + NSR_Mo + NSR_Ag) / 8235.6
Based on the NSR assumptions applied, this relationship simplifies to:
CuEq (%) = Cu (%) + 3.40327 × Mo (%) + 0.00008 × Ag (g/t)
The equivalent factors for molybdenum and silver are derived from the relative NSR contribution of each metal
compared to copper under the assumptions described above.
2. Net Smelter Return (NSR) cut-off is expressed in U.S. dollars and corresponds to CuEq cut-off using the simplified
formula NSR (US$/t) = (8235.6*CuEq%-1.4669)
3. The independent qualified persons for the MRE, as defined by National Instrument (“NI”) 43-101 guidelines, is Pierre-
Luc Richard, P.Geo., of PLR Resources Inc. with contributions from François Le Moal, P.Eng., of G-Mining for cut-off
grade and Pit shell optimization, and Christian Laroche, P.Eng., from Synectiq, for metallurgical parameters. The
effective date of the MRE is January 17, 2026.
4. These Mineral Resources are not Mineral Reserves as they have no demonstrated economic viability. No economic
evaluation of these Mineral Resources has been produced. The quantity and grade of reported Inferred Resources in
this MRE are uncertain in nature and there has been insufficient drilling to define these Inferred Resources as
Indicated. However, it is reasonably expected that the majority of Inferred Mineral Resources could be upgraded to
Indicated category with additional drilling.
5. The Qualified Persons are not aware of any known environmental, permitting, legal, title-related, taxation, socio-
political, financial, or other relevant issues that could materially affect the MRE.
6. Calculations used metric units (metres, tonnes). Metal contents in the above table are presented in per cent, pounds,
or tonnes. Metric tonnages and pounds were rounded, and any discrepancies in total amounts are due to rounding
errors.
7. CIM definitions and guidelines for Mineral Resource Estimates have been followed.
This MRE from the Gaspé Copper project continues to expand the resource and is the result of:
1. Higher long-term copper price estimates;
2. Geological re-interpretation of the deposit that has allowed for extension of the mineralized system to the south, beyond
the Copper Mountain porphyry stockwork system, into disseminated, stratigraphic replacement mineralization in skarns
and potassic-altered hornfels (porcellanites). This type of mineralization remains open to the south and towards Needle
Mountain to the southwest;
3. Reduction of cut-off grade from 0.12% Cu to 0.09% CuEq, based on higher long-term metal price estimates, larger
estimated mine throughput and replacement of SAG mill by HPGR in the grinding circuit (see Table 3 summarizing
Whittle shell parameters).
Potential for resource expansion
This updated MRE does not currently include any previously known mineralization in the area of the historic Needle Mountain
Open Pit, and its underlying B & C Zone skarns. Building upon the information released in this updated MRE and on Porphyry
Mountain, a minimum 50,000 metre drill program is planned to commence in May 2026 that will aim to 1) convert remaining
Inferred resources to Indicated category; 2) extend up-dip, shallower B-Zone and C-Zone skarn mineralization towards Needle
Mountain, which will comprise both infill drilling in the updated pit shell and testing of additional mineralization beyond current
pit boundaries to the south and southwest, and 3) test for depth extensions to the Porphyry Mountain deposit, located at
depth to the northeast of the Copper Mountain pit.
Implications of larger open pit at Gaspé Copper
The current modelled Whittle pit shell extends from the current flooded Copper Mountain pit towards the base of Needle East
Mountain to the south. Further drilling, geological modelling and pit optimization will be required to refine pit boundaries. There
is excellent potential for reducing strip ratio by optimizing the pit shell model and converting currently categorized in-pit waste
rock to mineralized material in the direction of Needle Mountain. The Company will evaluate future pit limits and the possibility
of reconfiguring the current layout of the site to minimize disturbance and ensure the protection and safety of the residents of
Murdochville and the surrounding environment.
General parameters of the updated MRE and Mineral Resource Sensitivity
This pit-constrained MRE uses a mathematical lower cut-off of 0.09% CuEq for pit shell optimization and a reporting cut-off
grade of 0.16% CuEq for base case in-pit resource estimation (see Table 2 below). The base case resource, emphasized to
disregard lower-grade marginal material, reflects a conservative higher cut-off grade of 0.16% CuEq. The mathematical lower
cut-off grade of 0.09% CuEq is based on estimated production costs, NSRs and consensus long-term metal prices of
US$4.50/lb copper, US$20 molybdenum, and US$45/oz silver (see Table 3 for detailed parameters). The resource was
estimated using data from historical drilling completed between the 1950s and 2019, and 160,000 metres of drilling completed
by the Company from 2022 to 2025, and on additional 2025 metallurgical and comminution test results.
Table 2: Mineral Resource Estimates at Variable Cut-Off Grades
Class
CuEq
Cut-off
(%)
NSR
Cut-off
(US$)
Tonnage
(Mt)
Strip
Ratio
Grade Copper Metal
Resource
Cu (%) Mo (%) M lbs kt
M&I 0.09 5.95 2,342 1.03 0.23 0.014 12,000 5,444
Inferred 0.09 5.95 287 0.36 0.014 2,264 1,027
M&I 0.10 6.77 2,283 1.08 0.24 0.014 11,893 5,396
Inferred 0.10 6.77 280 0.36 0.015 2,252 1,022
M&I 0.11 7.59 2,218 1.14 0.24 0.015 11,759 5,335
Inferred 0.11 7.59 273 0.37 0.015 2,238 1,015
M&I 0.12 8.42 2,147 1.21 0.25 0.015 11,600 5,263
Inferred 0.12 8.42 265 0.38 0.015 2,222 1,008
M&I 0.13 9.24 2,070 1.29 0.25 0.015 11,416 5,180
Inferred 0.13 9.24 259 0.39 0.015 2,208 1,002
M&I 0.14 10.06 1,993 1.37 0.26 0.016 11,216 5,089
Inferred 0.14 10.06 253 0.39 0.015 2,194 995
M&I 0.15 10.89 1,912 1.47 0.26 0.016 10,995 4,989
Inferred 0.15 10.89 246 0.40 0.016 2,177 988
M&I 0.16 11.71 1,834 1.57 0.27 0.017 10,766 4,885
Inferred 0.16 11.71 239 0.41 0.016 2,158 979.3
M&I 0.17 12.53 1,755 1.69 0.27 0.017 10,522 4,774
Inferred 0.17 12.53 231 0.42 0.016 2,136 969
M&I 0.18 13.36 1,676 1.81 0.28 0.017 10,266 4,658
Inferred 0.18 13.36 224 0.43 0.016 2,116 960
M&I 0.19 14.18 1,597 1.94 0.28 0.018 9,997 4,536
Inferred 0.19 14.18 217 0.44 0.016 2,094 950
M&I 0.20 15.00 1,517 2.09 0.29 0.018 9,715 4,408
Inferred 0.20 15.00 208 0.45 0.016 2,068 938
Same footnotes as Table 1 apply to this table.
Table 3 – Whittle optimization parameters used for the Mineral Resource Estimate (all monetary values in US$;
based on average mill throughput of 160,000 tonnes per day)
Economic Parameters
U.S./Canada Exchange rate 1.35
Discount rate % 8.0%
Cu Price $/lb $4.50
Mo Price $/lb $20.00
Ag Price $/oz $45.00
Refining Cu 'RC' $/lb $0.08
Refining Mo $/lb $0.00
Refining Ag $/oz $0.00
Royalty rate % NSR 2.40%
Concentrate Costs
Transport and loading costs (CAD$29.70) $/wmt $22.00
Shipping cost (CAD$89.44) $/wmt $66.25
Insurance and other costs (CAD$16.20) $/wmt $12.00
Smelter Treatment Cost Cu 'TC' $/dmt $80.00
Smelter Treatment Cost Cu 'TC' $/lb $0.34
Smelter Treatment Cost Mo 'TC' $/dmt $1,690.00
Smelter Treatment Cost Mo 'TC' $/lb $1.41
Concentrate Feed
Concentrate Grade Cu % 25%
Concentrate Moisture Cont. % 8%
Concentrate Grade Mo % 58%
Concentrate Moisture Cont. % 8%
Payables
Payable Cu % 96.5%
Payable Mo % 98.0%
Payable Ag % 75.0%
Recovery and Dilution Factors
Avg. Cu Recovery* (variable with grade) % 91%
Avg. Mo Recovery % 72%
Avg. Ag Recovery % 65%
Mining Dilution (Whittle) % 0%
Mining Recovery (Whittle) % 100%
Mineralized Material Base Costs
Processing Cost $/milled $4.15
% of rehandling % 10.00%
Stockpile Rehandle $/milled $0.16
G&A $/milled $0.90
Total $/milled $5.21
Mining Costs
Mined rock centre of gravity cost $/mined $2.00
Dump mining $1.30
Incremental mining cost $/mined/15m $0.05
NSR Calculations (before royalties)
NSR Cu $/t $21.42
NSR Mo $/t $4.88
NSR Ag $/t $1.14
Total NSR $/t $27.44
Copper Cut-Off grades
Mineralized material base cost $/t $5.21
Mining cost $/mined $2.00
Transport and Smelt cost $/t $1.87
Royalties cost $/t $0.66
Total cost $/t $9.74
Cu Break-Even Cut-Off Grade % Cu 0.111%
Mill Cut-Off value $/t $7.74
Cu Mill Cut-Off Grade % Cu 0.088%
Geotechnical Parameters
IRA slope in rock degrees 48
Net Payability
Net payability Cu % 87.1%
Net payability Mo % 91.0%
Net payability Ag % 75.0%
*The mill cut-off decreases to approximately $5.95/t at lower grades (e.g., 0.09% Cu and 0.008% Mo), as lower recoveries and
payable metal reduce the effective transport and smelting costs per tonne, resulting in a lower cut-off value. Results presented
above are with average grades of 0.27% Cu and 0.017% Mo.
Other parameters used for the Mineral Resource Estimate include:
• Resources are presented as undiluted and in situ for an open-pit scenario and are considered to have reasonable
prospects for economic extraction. The constraining pit shell was developed using overall pit slopes of 48 degrees in
bedrock and overburden. The pit optimization to develop the resource-constraining pit shells was performed using
Geovia Whittle 2022 software.
• The MRE model was prepared using Leapfrog Edge v. 2025.3.1 and is based on 2,793 drill holes and 208,043 samples.
The drill hole database includes recent drilling totalling 159,212 metres in 238 drill holes (Osisko Metals 2022-2025) and
incorporates historical drill holes totalling 570,422 metres in 2,555 drill holes (Glencore Canada 2019, Xstrata 2011-
2012, Noranda 1998 and earlier). Drill hole data verification was performed by verifying the coherence of the information
but not its correctness; original logs and laboratory certificates were only available for 2011, 2012, 2019, and 2022 to
2025 drill holes. The cut-off date for the drill hole database was January 17, 2026. The model included 17 mineralized
domains, one comprising the Copper Mountain stockwork zone and 16 others defined by stratabound mineralization in
skarn and porcellanites. Higher grade domains in the skarn horizons (greater than 1% Cu) were also separated into
eight subdomains with hard boundaries to avoid “grade smearing” in surrounding lower-grade lithologies during
interpolation.
• Composites of 5 to 10 metre lengths were created inside the mineralization volumes. A total of 40,142 composites were
generated. High-grade capping was done on the composited assay data. Composites were capped at 2.3% for Cu,
0.20% for Mo, and at 10g/t for Ag in the Copper Mountain stockwork zone, from 1.70% to 12.50% Cu, from 0.025% to
0.30% Mo, and from 15g/t to 85g/t Ag in the skarn and/or massive sulfide domains, and from 1.00% to 2.00% Cu, from
0.03% to 0.50% Mo, and from 10g/t to 60g/t Ag in the porcellanite domains.
• Pit-constrained Mineral Resources for the base case are reported at a lower cut-off grade of 0.16 % CuEq in sulfide
within a conceptual pit shell based on a 0.09% CuEq lower cut-off. The cut-off grades will be re-evaluated on an ongoing
basis considering future prevailing market conditions and costs.
• Contained copper in the resource includes sulfide copper only and soluble (oxide and carbonate) copper from surface
oxidized zones was excluded. It was assumed for this MRE that only the copper contained in sulfides could have
economical potential.
• Specific gravity values were estimated using data available in the historical drill holes as well as the 2022 to 2025
Osisko drilling. A total of 57,023 SG values were compiled, and values were interpolated for most of the mineralized
solids and a fixed value was used where the scarcity of the data did not allow for interpolation; the SG values range
from 2.46 to 3.99, and the average value is 2.77 tonnes/cubic metre. Surrounding barren lithologies were assigned the
average specific gravity value from all measured samples.
• The modelled base case pit shell measures 2,300 X 3,200 metres and reaches a maximum depth of approximately
1,150 metres.
• Grade model resource estimation was calculated from drill hole data using an ordinary kriging (OK) interpolation method
in a sub-blocked model using blocks measuring 15m x 15m x 15m in size and sub-blocks down to 1m x 1m x 1m.
• The Measured, Indicated and Inferred Mineral Resource categories are constrained to areas where drill spacing is less
than 60 metres, 120 metres, and 300 metres, respectively, and show reasonable geological and grade continuity.
Cautionary Statement Regarding Mineral Resources
The mineral resources disclosed in this news release conform to standards and guidelines in National Instrument 43-101 –
Standards of Disclosure for Mineral Projects (“NI 43-101”) and were prepared by independent qualified persons for purposes of
NI 43-101. The above-mentioned mineral resources are not mineral reserves as they do not have demonstrated economic
viability. The quantity and grade of the reported Inferred Mineral Resources are conceptual in nature and are estimated based
on limited geological evidence and sampling. Geological data is sufficient to imply but not verify geological grade and/or
quality of continuity. An Inferred Mineral Resource has a lower level of confidence relative to a Measured or Indicated Mineral
Resource and constitutes an insufficient level of confidence to allow conversion to a Mineral Reserve. It is reasonably
expected, but not guaranteed, that the majority of Inferred Mineral Resources could be upgraded to Measured or Indicated
Mineral Resources with additional drilling. The technical report prepared in accordance with NI 43-101, including the mineral
resources for the Gaspé Copper Project contained in this news release, will be delivered and filed on SEDAR+
(www.sedarplus.ca) under Osisko Metals’ issuer profile within 45 days of the date of this news release.
Qualified Person
The Mineral Resource Estimate and other scientific and technical information in this news release has been prepared and
approved by independent qualified persons for purposes of NI 43-101: Pierre-Luc Richard, P.Geo., of PLR Resources Inc. with
contributions from François Le Moal, P.Eng., of G-Mining for cut-off grade and Pit Shell optimization and Christian Laroche,
P.Eng., from Synectiq, for metallurgical parameters.
Quality Assurance / Quality Control
Osisko Metals adheres to a strict QA/QC program for core handling, sampling, sample transportation and analyses, including
insertion of blanks and standards in the sample stream. Drill core is drilled in HQ or NQ diameter and securely transported to
its core processing facility on site, where it is logged, cut and sampled. Samples selected for assay are sealed and shipped to
ALS Canada Ltd.’s preparation facility in Sudbury. Sample preparation details (code PREP-31DH) are available on the ALS
Canada website. Pulps are analyzed at the ALS Canada Ltd. facility in North Vancouver, BC. All samples are analyzed by four
acid digestion followed by both ICP-AES and ICP-MS for Cu, Mo, and Ag.
About Osisko Metals
Osisko Metals Incorporated is a Canadian exploration and development company creating value in the critical metals sector,
with a focus on copper and zinc. The Company acquired a 100% interest in the past-producing Gaspé Copper mine from
Glencore Canada Corporation in July 2023. The Gaspé Copper mine site is located near Murdochville in Québec's Gaspé
Peninsula. The Company is currently focused on resource expansion of the Gaspé Copper system, with current Measured
and Indicated Mineral Resources of 1.83 Bt averaging 0.32% CuEq and Inferred Mineral Resources of 239 Mt averaging
0.46% CuEq (in compliance with NI 43-101). For more information, see this news release entitled "Osisko Metals Announces
Significant Increase in Mineral Resource at Gaspé Copper". Gaspé Copper hosts the largest undeveloped copper resource in
eastern North America, strategically located near existing infrastructure in the mining-friendly province of Québec.
In addition to the Gaspé Copper project, the Company is working with Appian Capital Advisory LLP through the Pine Point
Mining Limited joint venture to advance one of Canada's largest past-producing zinc mining camps, the Pine Point project,
located in the Northwest Territories. The current mineral resource estimate for the Pine Point project consists of Indicated
Mineral Resources of 49.5 Mt averaging 5.52% ZnEq and Inferred Mineral Resources of 8.3 Mt averaging 5.64% ZnEq
(in compliance with NI 43-101). For more information, see Osisko Metals' June 25, 2024 news release entitled "Osisko Metals
releases Pine Point mineral resource estimate: 49.5 million tonnes of indicated resources at 5.52% ZnEq". The Pine Point
project is located on the south shore of Great Slave Lake, NWT, close to infrastructure, with paved road access, an electrical
substation and 100 kilometres of viable haul roads.
For further information on this news release, visit www.osiskometals.com or contact:
Don Njegovan, President
Email: [email protected]
Phone: (416) 500-4129
Cautionary Statement on Forward-Looking Information
This news release contains "forward-looking information" within the meaning of applicable Canadian securities legislation
based on expectations, estimates and projections as at the date of this news release. Any statement that involves
predictions, expectations, interpretations, beliefs, plans, projections, objectives, assumptions, future events or performance
(often, but not always, using phrases such as "expects", or "does not expect", "is expected", "interpreted", “management's
view", "anticipates" or "does not anticipate", "plans", "budget", "scheduled", "forecasts", "estimates", "potential", "feasibility",
"believes" or "intends" or variations of such words and phrases or stating that certain actions, events or results "may" or
"could", "would", "might" or "will" be taken, occur or be achieved) are not statements of historical fact and may be forward-
looking information and are intended to identify forward-looking information. This news release contains forward-looking
information pertaining to, among other things: the tax treatment of the FT Units; the timing of incurring the Qualifying
Expenditures and the renunciation of the Qualifying Expenditures; the ability to advance Gaspé Copper to a construction
decision (if at all); the ability to increase the Company's trading liquidity and enhance its capital markets presence; the
potential re-rating of the Company; the ability for the Company to unlock the full potential of its assets and achieve success;
the ability for the Company to create value for its shareholders; the advancement of the Pine Point project; the anticipated
resource expansion of the Gaspé Copper system and Gaspé Copper hosting the largest undeveloped copper resource in
eastern North America.
Forward-looking information is not a guarantee of future performance and is based upon a number of estimates and
assumptions of management, in light of management's experience and perception of trends, current conditions and expected
developments, as well as other factors that management believes to be relevant and reasonable in the circumstances,
including, without limitation, assumptions about: the ability of exploration results, including drilling, to accurately predict
mineralization; errors in geological modelling; insufficient data; equity and debt capital markets; future spot prices of copper
and zinc; the timing and results of exploration and drilling programs; the accuracy of mineral resource estimates; production
costs; political and regulatory stability; the receipt of governmental and third party approvals; licenses and permits being
received on favourable terms; sustained labour stability; stability in financial and capital markets; availability of mining
equipment and positive relations with local communities and groups. Forward-looking information involves risks, uncertainties
and other factors that could cause actual events, results, performance, prospects and opportunities to differ materially from
those expressed or implied by such forward-looking information. Factors that could cause actual results to differ materially
from such forward-looking information are set out in the Company's public disclosure record on SEDAR+ (www.sedarplus.ca)
under Osisko Metals' issuer profile. Although the Company believes that the assumptions and factors used in preparing the
forward-looking information in this news release are reasonable, undue reliance should not be placed on such information,
which only applies as of the date of this news release, and no assurance can be given that such events will occur in the
disclosed time frames or at all. The Company disclaims any intention or obligation to update or revise any forward- looking
information, whether as a result of new information, future events or otherwise, other than as required by law.