Coeur Provides Exploration Update for New Afton and Rainy River

Coeur Mining, Inc. (“Coeur” or the “Company”) (NYSE, TSX: CDE) today provided an update on recent exploration activities at its New Afton and Rainy River operations in Canada.

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Figure 1: Northwest slice through the New Afton deposit(s) highlighting K-Zone and significant 2026 drill intercepts (>0.36 g/t AuEq⁵)

Coeur is expected to invest a record $158 million¹ in exploration in 2026, more than double 2025 levels, which includes exploration investments of approximately $24 million² at New Afton and $18 million² at Rainy River. The combined programs at these recently acquired Canadian assets represent a double-digit increase in investment levels as compared to 2025, reflecting Coeur’s confidence in the long-term growth opportunities at both operations.

New Afton Mine: K-Zone Continues to Expand

Coeur continues to focus its exploration efforts at the K-Zone deposit, building on the maiden mineral resource of 48 million tonnes of measured and indicated resources and 6 million tonnes of inferred resources announced on March 23, 2026. New Afton’s 2025 proven and probable reserves totaled 36 million tonnes containing 780,000 ounces of gold at an average grade of 0.67 grams per tonne and 591 million pounds of copper at an average grade of 0.74%.

The infill drilling portion of the 2026 program has confirmed existing mineralization and outlined the potential for future upside to overall grades at K-Zone. The expansion drilling portion of this year’s program has extended mineralization by more than 300 meters beyond the original footprint of approximately 850 meters.

Areas of recent growth at K-Zone have been mainly to the west and to the southeast. In the western portion of K-Zone (see Figures 1 and 2), previously referred to as the D-Zone Gap, mineralization has been extended by approximately 150 meters, with results confirming strong copper-gold mineralization between D-Zone and K-Zone. At the East Picrite Trend, drilling has extended the mineralized system by at least 100 meters to the southeast, returning broad, higher-than-expected mineralized intercepts that represent potential for further mineralization growth.

With western K-Zone drilling now complete, exploration will shift to the east, northeast and southeast areas. An underground exploration drift currently being developed is expected to provide access to test drill up to 450 meters of additional strike potential (see Figure 2).

Intercept highlights include (true widths)³:

K-Zone:

• 26.3 meters at 1.8 grams per tonne (“g/t”) gold and 1.84% copper and 20.0 meters at 0.6 g/t gold and 1.26% copper (EA26-631)

• 23.6 meters at 2.0 g/t gold and 2.00% copper and 33.4 meters at 0.3 g/t gold and 0.77% copper (EA26-641)

• 175.8 meters at 0.5 g/t gold and 0.88% copper (EA26-624)

• 33.1 meters at 1.5 g/t gold and 1.40% copper (EA26-644)

• 23.6 meters at 0.6 g/t gold and 1.15% copper and 23.9 meters at 0.2 g/t gold and 0.26% copper (EA26-628)

• 30.7 meters at 0.7 g/t gold and 0.69% copper and 11.5 meters at 0.3 g/t gold and 0.51% copper (EA26-632)

East Picrite Trend:

• 124.6 meters at 1.1 g/t gold and 1.25% copper and 29.8 meters at 0.7 g/t gold and 1.00% copper (EA26-623)

• 64.1 meters at 1.1 g/t gold and 1.36% copper (EA26-630B)

• 88.6 meters at 1.0 g/t gold and 1.44% copper (EA25-569B)

• 68.7 meters at 1.0 g/t gold and 1.49% copper and 39.5 meters at 0.3 g/t gold and 0.25% copper (EA26-640)

Rainy River: Strong Open Pit and Underground Growth Potential

Exploration at Rainy River continues to demonstrate significant growth potential across both underground and near-surface targets. In 2026, underground drilling is focused on extending and infill drilling higher-grade shoots and testing gaps between existing shoots, while surface drilling is targeting open pit growth opportunities between the Phase 5 and Northwest Trend (“NWT”) pits (see Figures 3 and 4), and regional exploration programs have resumed.

Expansion drilling has extended multiple underground mineralized zones, including the ODM Main Zone by more than 150 meters and Zone 17 by more than 200 meters down-plunge. At Intrepid, mineralization was extended 40 meters to the east along a 200-meter plunge extent. All underground zones remain open at depth (see Figure 3).

Infill drilling aimed at converting underground inferred mineral resources was completed across a significant 275 meter by 150 meter gap in the core of the ODM Main Zone, while also infilling other key underground zones including Zone 17 and the HS and 433 areas. The positive results are expected to support the potential upgrade of mineral resource classification from inferred to measured and indicated at year-end.

Surface reverse circulation (“RC”) drilling tested the continuation of mineralization both between and adjacent to the planned NWT and Phase 5 pits, with results supporting the potential for future open-pit connectivity between these areas.

These results reinforce Rainy River’s potential to expand both underground and open-pit mineral resources, while supporting mine-life extension and future production flexibility.

Intercept highlights include (true widths)³:

ODM Main Zone – Underground Expansion:

• 8.1 meters at 14.8 g/t gold and 3 g/t silver (RR26-2119B)

• 7.9 meters at 10.8 g/t gold and 5 g/t silver (RR26-2123)

• 5.8 meters at 3.6 g/t gold and 7 g/t silver (RR26-2108-W2)

Zone 17 – Underground Expansion:

• 5.8 meters at 43.6 g/t gold and 13 g/t silver (RR26-2110-W1A)

• 10.5 meters at 5.6 g/t gold and 1 g/t silver (RR26-2109-W1)

• 11.6 meters at 1.8 g/t gold and 3 g/t silver (RR26-2109)

ODM Main Zone – Underground Infill:

• 4.3 meters at 10.3 g/t gold and 5 g/t silver (RR26-2112-W2)

• 13.4 meters at 1.8 g/t gold and 1 g/t silver (RR26-2113)

• 3.3 meters at 12.9 g/t gold and 3 g/t silver (RR25-2081-W1)

NWT and Phase 5 – Open Pit Infill:

• 6.0 meters at 4.8 g/t gold (RC26-025)

• 15.8 meters at 1.1 g/t gold (RC26-015)

• 11.6 meters at 0.7 g/t gold (RC26-008)

“These results underscore the excellent growth potential within our newly acquired Canadian operations,” said Aoife McGrath, Executive Vice President, Exploration. “At New Afton, Coeur is advancing the K-Zone, one of its most compelling growth opportunities within the portfolio. Since the acquisition, exploration at K-Zone has continued to deliver strong results, confirming the existing mineral resource while extending the mineralized system well beyond the original footprint. With dedicated underground development providing access to new exploration fronts, we see considerable runway for further expansion and value creation. At Rainy River, ongoing expansion and infill drilling continue to demonstrate the opportunity to grow both underground and open-pit mineral resources, while regional programs continue to refine future drill targets. These results reinforce our confidence in extending mine life and creating long-term value at both operations.”

For a complete table of all drill results, please refer to the following link: https://www.coeur.com/New-Afton-and-Rainy-River-Exploration-Appendix/. Please see the “Cautionary Statements” section for additional information regarding drill results.

New Afton Mine, British Columbia

Coeur’s $24 million² 2026 exploration budget at New Afton includes 68 kilometers of core drilling, primarily focused on expanding and upgrading the maiden K-Zone mineral resource (see Figure 1), which was released in March 2026 with measured and indicated and inferred mineral resources of 48 million tonnes and 6 million tonnes, respectively. The additional core drilling is expected to support ongoing engineering studies related to its development.

Since the discovery of K-Zone in late 2023, over 109 kilometers of core drilling have been completed, which has grown the deposit⁴ to more than 1,100 meters along strike and 1,100 meters vertically. The rapid progression from discovery to substantial mineral resource underscores the significant growth potential near existing underground infrastructure.

Rainy River Mine, Ontario

Underground Zones Extended Down-Plunge; Core of ODM Main Zone Infilled

The $18 million² 2026 exploration budget at Rainy River is focused on growing and converting underground and open pit mineral resources, while initiating regional exploration activities. A total of approximately 64 kilometers of core drilling targeting underground mineralization is planned for full-year 2026, with 43 kilometers completed across 51 holes as of August 30, 2026. Key takeaways from the programs include:

Expansion Drilling

• Zone 17: Down-plunge drilling has extended mineralization over 200 meters below current mineral resource

• ODM Main Zone: Down-plunge drilling along the eastern portion of the zone has extended mineralization over 150 meters below the current mineral resource

• Intrepid: Step-out drilling has extended the eastern portion of mineralization laterally by approximately 40 meters and down plunge by more than 200 meters

• 114 Zone – Phase 5: Core drilling within the 114 Zone below the Phase 5 pit and current mineral resource has identified additional mineralization that remains open at depth

Infill Drilling

• ODM Main Zone: Infilled a 275 by 150 meter gap of inferred mineralization to support future mineral resource conversion

• Zone 17 & HS/433: Further delineated and expanded mineralized zones. The HS/433 mineralization occurs as subparallel stacked lenses north of the ODM Main Zone (see plan view on top of Figure 3)

Core drilling for the remainder of the year is expected to continue advancing these expansion and infill programs, in addition to testing for new underground mineralization between existing ore shoots.

Near-Surface Mineralization Extended Beyond Current Open-Pit Footprint

In 2026, a 24-hole, 3,863 meter near-surface RC drilling program successfully targeted the saddle between the planned Northwest Trend and Phase 5 pits. A total of 12 of the 24 drill holes intersected mineralization that met or exceeded expectations. The program aimed to test mineralization continuity beyond the main orebody footprint and to support the evaluation of potential pit expansions through pit optimization and strip ratio improvements.

Additionally, regional exploration programs are in progress across Rainy River’s approximately 41,800-hectare property to evaluate mineral potential. Early-stage exploration programs underway include property-scale till sampling, geophysical surveys (mobile magnetotellurics), geological mapping, and prospecting. Results are expected to inform 2027 exploration targeting and regional core drilling.

Ongoing success across both underground and open-pit core drilling programs reinforces Rainy River’s long-term growth potential. These programs continue to demonstrate strong mineralization continuity across key zones while supporting engineering evaluations of open-pit and underground expansion opportunities.

About Coeur

Coeur Mining, Inc. is a U.S.-based, well-diversified, growing precious metals producer with seven wholly-owned operations: the New Afton gold-copper mine in British Columbia, Canada, the Rainy River gold-silver mine in Ontario, Canada, the Las Chispas silver-gold mine in Sonora, Mexico, the Palmarejo gold-silver mine in Chihuahua, Mexico, the Rochester silver-gold mine in Nevada, the Kensington gold mine in Alaska and the Wharf gold mine in South Dakota. In addition, the Company wholly-owns the Silvertip polymetallic critical minerals exploration project in British Columbia, Canada.

Cautionary Statements

This news release contains forward-looking statements within the meaning of securities legislation in the United States and Canada, including statements regarding mineral reserve and mineral resource estimates, exploration efforts and plans, growth, mine lives, mine expansion and development plans, and resource delineation, expansion, and upgrade or conversion. Such forward-looking statements involve known and unknown risks, uncertainties, and other factors that may cause Coeur’s actual results, performance, or achievements to be materially different from any future results, performance, or achievements expressed or implied by the forward-looking statements. Such factors include, among others, the risk that anticipated additions or upgrades to reserves and resources are not attained, the risk that planned exploration programs may be curtailed or canceled due to budget constraints or other reasons, the risks and hazards inherent in the mining business (including risks inherent in developing large-scale mining projects, environmental hazards, industrial accidents, weather or geologically related conditions), changes in the market prices of gold, silver, and copper, and a sustained lower price environment, the uncertainties inherent in Coeur’s production, exploratory, and developmental activities, including risks relating to permitting and regulatory delays, ground conditions, grade and recovery variability, any future labor disputes or work stoppages, the uncertainties inherent in the estimation of mineral reserves and mineral resources, the potential effects of pandemics or epidemics, including impacts to the availability of our workforce, continued access to financing sources, government orders that may require temporary suspension of operations at one or more of our sites and effects on our suppliers or the refiners and smelters to whom the Company markets its production, changes that could result from Coeur’s future acquisition of new mining properties or businesses, the loss of any third-party smelter to which Coeur markets its production, the effects of environmental and other governmental regulations, the risks inherent in the ownership or operation of or investment in mining properties or businesses in foreign countries, Coeur’s ability to raise additional financing necessary to conduct its business, make payments, or refinance its debt, as well as other uncertainties and risk factors set out in filings made from time to time with the United States Securities and Exchange Commission and the Canadian securities regulators, including, without limitation, Coeur’s most recent reports on Form 10-K and Form 10-Q. Actual results, developments, and timetables could vary significantly from the estimates presented. Readers are cautioned not to put undue reliance on forward-looking statements. Coeur disclaims any intent or obligation to update publicly such forward-looking statements, whether as a result of new information, future events, or otherwise. Additionally, Coeur undertakes no obligation to comment on analyses, expectations, or statements made by third parties in respect of Coeur, its financial or operating results, or its securities.

The scientific and technical information concerning our mineral projects in this news release has been reviewed and approved by a “qualified person” under Item 1300 of Regulation S-K under the Securities Exchange Act of 1934, as amended (“SK 1300”), namely our Senior Vice President, Technical Services, Christopher Pascoe. For a description of the key assumptions, parameters, and methods used to estimate mineral reserves and mineral resources for Coeur’s material properties included in this news release, as well as data verification procedures and a general discussion of the extent to which the estimates may be affected by any known environmental, permitting, legal, title, taxation, sociopolitical, marketing, or other relevant factors, please review the Technical Report Summaries for each of the Company’s material properties, which are available at www.sec.gov.

Notes

The ranges of potential tonnage and grade (or quality) of the exploration results described in this news release are conceptual in nature. There has been insufficient exploration work to estimate a mineral resource. It is uncertain if further exploration will result in the estimation of a mineral resource. The exploration results described in this news release therefore do not represent, and should not be construed to be, an estimate of a mineral resource or mineral reserve. For additional information regarding 2025 mineral reserves and mineral resources, see https://www.coeur.com/operations/operations/reserves-resources/.

1. Figure reflects the midpoint of guidance as published by Coeur on August 5, 2026.

2. Full-year planned total(s) include exploration spending and core drilling amounts in early 2026 prior to Coeur’s acquisition of New Gold Inc. on March 20, 2026. The amounts included from pre-acquisition are approximately $4 million of exploration spending and 19 kilometers of drilling at New Afton and $3 million of exploration spending and 16 kilometers of drilling at Rainy River.

3. All drill intervals are estimated true widths. Rounding of grades, to significant figures, may result in apparent differences. For a complete table of all drill results included in this release, please refer to the following link: https://www.coeur.com/New-Afton-and-Rainy-River-Exploration-Appendix.

4. As defined by the 0.18 g/t gold equivalent (“AuEq”) envelope.

5. Gold equivalent calculation assumes a gold-to-copper conversion ratio of 1 oz Au to 600 lb Cu.

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