15.18.10	Contact Water Collection Ponds	298
		15.18.11	Starter Buttress	298
		15.18.12	Filtered Tailings	299
		15.18.13	Coarse Graded Filtered Tailings Cover	299
		15.18.14	FTSF Construction	299
		15.18.15	Contact Water Collector Channels and Collection/Storage Ponds	300
		15.18.16	Surface Water Monitoring	300
		15.18.17	Groundwater Monitoring	300
	15.19	Off-Site Facilities		300
		15.19.1	Assay Laboratory	300
16	MARKET STUDIES AND CONTRACTS			301
	16.1	Market Studies		301
	16.2	Refining Terms and Conditions		302
	16.3	Metal Pricing		302
	16.4	Contracts		302
	16.5	Deleterious Elements		302
	16.6	Comments on Market Studies and Contracts		302
17	ENVIRONMENTAL STUDIES, PERMITTING, AND SOCIAL OR COMMUNITY IMPACT			303
	17.1	Environmental Review		303
		17.1.1	Baseline and Supporting Studies	303
		17.1.2	Geochemistry	304
		17.1.3	Environmental Liabilities	305
	17.2	Permitting		305
		17.2.1	Overview	305
		17.2.2	Permits to Support Construction and Operations	305
	17.3	Mining Waste and Water Management		311
		17.3.1	Waste Rock and Tailings Management	311
		17.3.2	Water Management	311
	17.4	Social and Community Requirements		311
		17.4.1	Population and Demographics	311
		17.4.2	Local Hiring, Procurement and Sponsorship	312
		17.4.3	Community Engagement and Relationship Management	312
		17.4.4	Stakeholder Identification and Materiality Analysis	314
		17.4.5	Disclosure of Socioeconomic Risk	315
		17.4.6	Indigenous Communities	315
	17.5	Closure Considerations		315
		17.5.1	Conceptual Closure Plan	315

 

 

 

 

 

Coeur Mining, Inc. (Coeur Mining or the Company) is listed on the New York Stock Exchange (NYSE). As a result, Coeur Mining is a registrant with the United States Securities and Exchange Commission (SEC) and must comply with the subpart 229.1300 – Disclosure by registrants Engaged in Mining Operations of Regulation S-K (S-K 1300).

 

Coeur Mining commissioned Ausenco Engineering ULC. (Ausenco) to complete a Technical Report (the Report) prepared in accordance with S-K 1300 on the Las Chispas Operation (the Las Chispas Operation), located in Sonora, Mexico for the purposes of the Company’s acquisition of SilverCrest Metals Inc (SilverCrest). The effective date (the Effective Date) for the Report is December 31, 2024.

 

The Report was prepared by Ausenco Engineering Canada ULC (Ausenco), P&E Mining Consultants Inc. (P&E), Christopher Pascoe, RM SME, and Joseph Wallick, RM SME for Coeur Mining to file with and support disclosures in Coeur's 10-K.

 

Mineral Resources and Mineral Reserves are reported in accordance with Subpart 229.1300 – Disclosure by Registrants Engaged in Mining Operations (S-K 1300).

 

All units of measurement in the Report are metric, unless otherwise stated. The monetary units are in US dollars, unless otherwise stated.

 

 

The City of Hermosillo is 220 km southwest of the Las Chispas Operation, or a three-hour drive; Tucson, Arizona (USA) is located 350 km northwest of the Las Chispas Operation, or a five-hour drive; and the community and large copper mine in Cananea is located 150 km to the north along Highway 89, or a two-and-a-half-hour drive. The closest villages are Banamichi, 25 km to the southwest, and Arizpe, located 12 km to the northeast. The closest resident to the Las Chispas Operation, a single ranch house, is 10 km to the west.

 

Mining supplies and services are readily available from the towns of Cananea, Hermosillo, and Tucson. Labor and skilled workforces exist in the nearby communities, including Banamichi and Arizpe, for which transportation routes have been established to support the mining operation. A 500-bed accommodation camp is available at the Las Chispas Operation and housing is also available in the nearby communities.

 

The Las Chispas Operation is connected to the national electricity grid via a 33 kV power line with an overall capacity of 7.6 MW. This capacity is sufficient for life of mine (LOM).

 

The Las Chispas Operation is accessed from the community of Arizpe via secondary gravel roads, 10 km from the paved highway. The Sonora River crossing is possible via the recently built 171 m long Tetuachi Bridge. The remainder of the road has been upgraded to support construction and operation-related traffic.

 

The climate for the Sonoran Desert, with a dry season from October to May. Seasonal temperatures vary from 0° to 40°C. Average rainfall is estimated at 300 mm/year, but it can vary substantially. Operations are being conducted year-round.

 

The Las Chispas Operation is located on the western edge of the north-trending Sierra Madre Occidental Mountain range geographically adjacent to the Sonora Valley. Surface elevations range from 950 m  to 1,375 m above sea level (masl).

 

Drainage valleys generally flow north to south, and east to west towards the Sonora River. During the rainy season, flash flooding can occur in the area.

 

Vegetation is scarce during the dry season and limited primarily to juvenile and mature mesquite trees and cactus plants. During the wet season, various blooming cacti, trees, and grasses are abundant in drainage areas and on hillsides.

 

 

The Las Chispas Property (Figure 3‑1) is located in the State of Sonora, Mexico and is centred at approximate 30.233902°N latitude and 110.163396°W longitude (Universal Transverse Mercator [UTM] World Geodetic System [WGS]84: 580,500E, 3,344,500N), within the Arizpe Mining district.

 

The Las Chispas Property consists of 27 mineral concessions, totaling 1,414 ha, which are held by Coeur Mining’s  wholly-owned subsidiary, Compañía Minera La Llamarada S.A. de C.V. (LLA). Concessions have expiry dates that range from 2039-2073. One concession is in the grant process, and one concession is the subject of legal proceedings following cancellation. The mineral concessions that host the Mineral Resources and Mineral Reserves are in good standing. At the Report Effective Date, all required mining duties were paid.

 

The surface rights overlying the Las Chispas Property mineral concessions and road access from local highway are either owned by LLA or held by LLA under a negotiated 20-year lease agreement with the Ejido Bamori. LLA has purchased the Cuesta Blanca and Babicanora ranches and signed a 20-year lease agreement for a portion of the Tetuachi Ranch. Surface rights are sufficient for the proposed LOM plan and include the locations of the necessary infrastructure as presented in the Report. On February 2, 2023, LLA purchased the La Higuerita Ranch situation in the municipality of Arizpe, Sonora.

 

A 2% royalty is payable on the Nuevo Lupena and Panuco II concessions for material that has processed grades of ≥0.5 oz/tonne gold and ≥40 oz/tonne silver, combined. These two concessions do not include Mineral Reserves.

 

This Report assumes that production water will be from the 900 level (900 m from surface or 850 masl) of the historical Las Chispas Mine and from the Sonora Valley within the Las Chispas Property limit and near the main access road to the site. This combined source of water is considered representative of the regional water table, has been tested, and is adequate in quantity and quality for exploration and production purposes. LLA has sufficient water rights for operations.

 

 

Historical records indicated mining around the Las Chispas Operation area started as early as the 1640s. The historical records available on mining activities in the 1800s and 1900s are incomplete. Many small mines were operated during the period 1900 to 1930. A gap exists in mining activity records for Las Chispas between the mid-1930s through to 1974. A small mill operated offsite from 1974 to 1984, treating material from historical mine dumps.

 

Minefinders Corporation Ltd. (Minefinders) conducted geological mapping and a geochemical sampling program consisting of stream sediment and bulk-leach extractable gold (BLEG) samples, underground and surface rock chip sampling, and completing seven (7) reverse circulation (RC) drill holes (1,843 m) to test potential mineralization adjacent to the Las Chispas mineralized northwest-southeast trend. The drill results were not encouraging.

 

SilverCrest obtained the rights to the Las Chispas Operation area in 2015.

 

Coeur Mining’s subsidiary obtained the rights to the Las Chispas Operation area in February 2025.

 

Historical exploration and mining work included small mining and processing operations, geological mapping, surficial geochemical sampling, underground and surface rock chip sampling, and reverse circulation drilling.

 

 

Mineral deposits in the Las Chispas District are classified low to intermediate sulfidation gold and silver epithermal systems, of many deposits in Sonora, Mexico.

 

Regionally, the Las Chispas mineralization is situated in an extensional basin related to a Late Oligocene half-graben of the Sonora River Basin. Multiple stages of normal faulting affect the basin. The main structures are steep, west-dipping and sub-parallel to the Santa Elena-Las Chispas normal fault, which is located along the western margin of the Las Chispas Operation, striking approximately 210°. The basin is further cross-cut by younger northwest–southeast trending normal faults that dip to the southwest, creating both regional and local graben structures. Locally, the graben structures are complicated by the effects of probable caldera collapse.

 

Mineralization is hosted in hydrothermal veins, stockwork, and breccia. Emplacement of the mineralization is influenced by fractures and low-pressure conduits formed within the rocks during tectonic movements. Mineralization can be controlled lithologically along regional structures, local tension cracks, and faulted bedding planes. Brecciated mineralization formed in two ways: 1) in zones of low pressure as hydrothermal breccia; and 2) as mechanical breccias. These breccia types are interpreted to occur at the intersection of two or more regional structural trends. The mineralization is 0.10–10 m in true thickness and typically encompasses a central quartz ± calcite mineralization corridor with narrow veinlets within the adjacent fault damage zone. Stockwork and breccia zones are centered on structurally controlled hydrothermal conduits.

 

Generally, it appears that epithermal mineralization is higher in the system (closer to the paleo-surface) on the west side (e.g. La Victoria Vein and historical mine) compared to the east side (e.g., Granaditas Vein and historical mine) of the Las Chispas District, where there is an increase in base metal content.

 

Silver visually dominates over gold mineralization throughout the Las Chispas Operation. Acanthite is the principal silver mineral, although electrum and native silver can also be present. Silver is associated with galena, pyrite ± marcasite, and chalcopyrite. Gold occurs as electrum, native flakes and in association with pyrite and chalcopyrite. Locally, gold and silver values have a strong positive correlation with each other. Base metal contents are low in veins, although they tend to increase towards the southeast.

 

The Las Chispas Operation is divided into the Las Chispas Area and the Babicanora Area and currently has 76 epithermal veins, not including seven bifurcations.

 

 

Prior to Coeur Mining’s acquisition of SilverCrest, the latter completed several phases of exploration from 2016 to 2024.

 

Chip samples and (or) channel samples were collected from historical underground workings in the Las Chispas Area and newly developed in-vein drifting in the Babicanora Area. A total of 23,104 underground channel sample results were collected as of the data cut-off date for this Report. In the Babicanora Main Vein system, 8.4 km of strike length have been developed and sampled, mostly in the Babicanora Main Vein. In the Babicanora Norte Vein system, 2.7 km of strike length has been developed and sampled. In Babi Vista Vein system, 4.3 km have been developed and sampled. In the Las Chispas area, 30 m of new development were sampled.

 

Underground continuous channel samples were marked horizontally across the face by a geologist, based on mapping, per lithology or mineralization contacts, using spray paint prior to sample collection. Sample lengths varied by thickness of the geological contact and were set to a minimum of 0.30 m in mineralization to a maximum of 1.5 m in waste.

 

Two long cuts 5 cm deep and separated by 10 cm were made parallel to the sample line using a pneumatic rock saw. Then, several short cuts perpendicular to the sample line were made at the contacts and between contacts. The rock is removed from the channel using a small sledgehammer and hand maul, or pneumatic chipper, and placed on a small tarp on the floor. The channel is inspected by the geologist for uniform width and depth across the sample, and to verify that the minimum sample mass is at least 1 kg. Samples are collected and placed into clear plastic sample bags with a sample tag, secured with a zip tie, labelled, and then stored in a fenced and locked facility at the Mine, prior to being transported to SGS Arizpe for analysis.

 

A total of 65,610 bulk density measurements were collected on-site using the water immersion method. Seventy-two (72) samples were tested by ALS Chemex (ALS) based in Hermosillo, Mexico for wax-coated bulk density to validate the on-site measurements.

 

In November 2018, two samples were collected and sent to Geotecnia del Noroeste S.A. de C.V. based in Hermosillo, for wax coated dry bulk density testing. The bulk density values ranged from 1.53 to 4.02 t/m³, with a mean value of 2.52 t/m³. A uniform mean bulk density of 2.55 t/m³ was applied to all rock types in the Mineral Resource Estimate, based on the results of the bulk density test work completed on-site and at the two laboratories.

 

All samples collected from drilling up to January 30, 2024, were assayed by ALS in Hermosillo, ALS in Vancouver, BC, Canada, and Bureau Veritas Minerals Laboratories (Bureau Veritas, formally Inspectorate Labs) in Hermosillo.

The samples were re-run using FA with gravimetric detection, and where gold values were >10 gpt, the samples were re-run using 30 g FA with AAS detection. Samples returning grades >10,000 ppm Zn, Pb, or Cu from ICP-MS analysis were re-run using aqua regia digestion with ICP-AES finish. In 2022, SGS entered into Agreement with SGS de Mexico S.A. de C.V, a subsidiary of the global SGS SA, to design and operate a sample preparation and analytical laboratory in the nearby community of Arzipe, Mexico. The SGS laboratory was built as a business venture to support the Arizpe community while providing prioritized sample preparation and analysis for the Las Chispas Mine and Exploration activities. The facility commenced operations and receiving grade control samples from Las Chispas in April, 2022. Since then, ALS Hermosillo has been used on a monthly basis as an umpire lab for verification analysis and quality control. In December 2023, the SGS Arizpe lab received accreditation from the Entidad Mexicana de Accreditacion (EMA) for their ISO/IEC 17025:2017 certification on the ICP, atomic absorption and fire assay analytical procedures and has since also served as the primary analytical facility to support Exploration activities.

 

The quality assurance/quality control (QA/QC) program consisted of certified reference material (CRM), and blank sample insertions at a rate of 1:50 for all sample types being collected, and insertion of duplicate samples for some underground chip samples, core pulps and coarse rejects. CDN Resource Laboratories Ltd. was the source of the CRMs. The mine and brownfields Exploration activities are presently using three custom CRMs prepared from Grade Control reject material. The blank samples were collected from a local silica cap.

 

The sample preparation, analysis, and security program implemented by SilverCrest was designed with the intent to support collection of a large volume of data. Sample collection and handling routines were well-documented. The laboratory analytical methods, detection limits, and grade assay limits are suited to the style and grade of mineralization. The QA/QC methods implemented by Las Chispas Operations enabled assessment of sample security, assay accuracy, and potential for contamination. The QP reviewed sample collection and handling procedures, laboratory analytical methods, QA/QC methods, and QA/QC program results and considers these methods are adequate to support the current Mineral Resource Estimate.

 

 

Prior to the acquisition of SilverCrest by Coeur Mining, SilverCrest completed several drilling program phases from 2016 to 2024.

 

SilverCrest completed their Phase I and Phase II drilling programs between March 2016 and February 2018. The Phase III drilling program included drilling up to February 2019. The Phase III Extended drilling program, starting in February 2019, focused on in-fill and expansion drilling and was completed on October 16, 2020, with a total of 309,383 m completed in 1,137 drill holes. Phase IV included drilling from October 2020 to June 2022 and focused mainly on infill and expansion of known veins with a total of 198,926 m completed in 1,041 drill holes. This Phase was known as the “Resource and Reserve” or “R&R Drill Program”. Phase V includes drilling from June 2022 to March 2023 and focused on expansion drilling for Inferred Mineral Resources, with a total of 223 drill holes completed for 64,755 m drilled and 40,332 samples collected for geochemical assay analysis. Phase V Extended includes drilling from March 22, 2023, to October 31, 2024, with a total of 258 drill holes completed for 82,599 m drilled and 47,952 samples collected for geochemical assay analysis. From the start of drilling in March 2016 through October 2024, 4,498 drill holes have been completed totaling 861,709 m drilled and 328,994 samples have been collected for geochemical assay analysis. Drilling data to October 31, 2024, were used in the Mineral Resource Estimate and in the Mineral Reserve Estimate.

 

Surface collar locations were initially surveyed using a handheld global positioning system (“GPS”) unit and subsequently were professionally surveyed by a local contractor. A survey was completed by external consultant David Chavez Valenzuela in October 2018. This survey was performed using a GNSS Acnovo GX9 UHF instrument. The remainder of the drill hole collar surveys to December 2019 were completed by Precision GPS S.A. de C.V. (Precision GPS) from Hermosillo, Sonora, Mexico, using a Trimble VX10 Total Station and a Trimble R8 GNSS GPS RTK system. Starting on January 2020, surveys have been conducted by Llamarada personnel using a Trimble R8 GNSS GPS RTK system. The survey provided drill collar locations, information on roads, and additional detail on property boundaries.

 

Until December 2019, underground exploration drill hole collars were surveyed by Precision GPS using the underground control points established for each of the workings. Starting in January 2020, all drill hole collars were surveyed by Llamarada personnel. All drill holes were surveyed downhole using single-shot measurements with aFlex-it tool starting at 15 m from the collar followed by measurements every 50 m to determine deviation. The survey measurements were monitoring downhole deviations and significant magnetic interference from the drill rods that would prevent accurate readings.

 

For any newly discovered veins, the first 10 drill holes are sampled from top to bottom. Additional drill holes could be entirely sampled, if such sampling were required to establish a greater understanding of geology and mineralization, but typically they are sampled 10 m before and after each mineralization zone intersected. Sample intervals are determined by mineralization, veining, and structure, with a minimum of 0.5 m sample lengths of mineralization and up to a maximum of 3 m in non-mineralized. Each sample interval was either split using a hand splitter or cut using a wet core saw, perpendicular to veining where possible, in order to leave representative core in the box and to reduce any potential bias in the sampled mineralization submitted with the sample. All samples assayed by ALS in Hermosillo, ALS in Vancouver, BC, Canada and Bureau Veritas Minerals Laboratories (Bureau Veritas, formally Inspectorate Labs) in Hermosillo, were crushed to 75% (ALS) or 70% (Bureau Veritas) minus 2 mm, and then mixed and split with a riffle splitter. A split from all samples was then pulverized to 80% (ALS) or 85% (Bureau Veritas) -75 µm. All pulverized splits were submitted for multi-element aqua regia digestion with inductively coupled plasma (ICP)-mass spectrometry (MS) detection, atomic emission spectroscopy (AES) or optical emission spectroscopy (OES) detection, and gold fire assay (FA) fusion with atomic absorption spectroscopy (AAS) detection. Samples returning assay grades >100 gpt Ag from ICP analysis were re-run using aqua regia digestion and ICP-atomic emission spectroscopy (AES) detection and diluted to account for grade detection limits (<1,500 g/t). Where Ag grades were ≥1,500 g/t, the sample was re-run using FA with gravimetric detection. During the Phase II drilling program, where gold values >1 g/t, the samples were re-run using FA with gravimetric detection, and where gold values were >10 g/t, the samples were re-run using 30 g FA with AAS detection. During Phase III, selective metallic screen analysis was completed at SGS Durango. During Extended Phase III, gold and silver were analyzed using 30 g FA with gravimetric finish. For the Phase IV definition and exploration drilling undertaken from October 2020 to October 2024, gold was analyzed using 30 g FA with gravimetric finish.

 

SGS entered into Agreement with SGS de Mexico S.A. de C.V, a subsidiary of the global SGS SA, to construct and operate a sample preparation and analytical laboratory in the nearby community of Arizpe, Sonora, Mexico. The facility commenced operations in April, 2022 initially receiving grade control samples from Las Chispas Operations. In December 2023, SGS announced that the Arizpe laboratory had obtained ISO/IEC 17025:2017 accreditation from the Mexican Accreditation Entity (EMA), with ISO/IEC 17025:2017 accreditation specifying the requirements for the competence, impartiality and constant operation of quality management in the lab. Since then, all definition and exploration drilling samples were also sent to SGS Arizpe, making the facility the primary lab used by Las Chispas Operations.

 

All samples were received, registered, dried at 105°C, and weighed, then crushed to 75% <2 mm, homogenized, and a 500 g split generated with a riffle splitter. The 500 g split was pulverized to ≥85% <75 µm (the “primary pulp”). From April 2022 to October 2024, all underground channel and chip samples were analyzed for gold by 30 g fire assay with AAS detection (GO_FAG37V). Samples returning grades >100 g/t Au were further analyzed by fire assay with gravimetric finish (GC_FAG33V). From April 2022 to November 2023, underground channel and chip samples were analyzed for silver by fire assay with AAS finish (GO_FAG37V) and by Aqua Regia digestion with ICP-OES finish (GE_ICP21B). From November 2023, method GE_ICP21B was discontinued. Samples returning grades >10,000 g/t Ag were further analyzed by fire assay with gravimetric finish (GC_FAG33V).

 

Definition drilling samples were analyzed for gold by 30 g fire assay with AAS detection (GO_FAG37V). Samples returning grades >100 g/t Au were further analyzed by fire assay with gravimetric finish (GC_FAG33V). Samples were initially analyzed for silver by fire assay with AAS finish (GO_FAG37V) and by Aqua Regia digestion with ICP-OES finish (GE_ICP21B). From June 2024, method GO_FAG37V was discontinued. Samples returning grades >10,000 g/t Ag were further analyzed by fire assay with gravimetric finish (GC_FAG33V).

 

Exploration drilling samples were analyzed for gold by 30 g fire assay with AAS detection (GO_FAA30V). Samples were analyzed for silver by Aqua Regia digestion with ICP-OES finish (GE_ICP21B). Samples returning grades >100 g/t Ag were further analyzed by fire assay with AAS finish (GO_FAG37V).

 

The quality assurance/quality control (“QA/QC”) program consisted of certified reference material (“CRM”), and blank sample insertions at a rate of at least 1:50 for all sample types being collected, and insertion of duplicate samples for some underground chip samples, core pulps and coarse rejects. The CRMs were purchased from CDN Resource Laboratories Ltd. The blank samples were collected from a local silica cap.

 

The sample preparation, analysis, and security program implemented was designed with the intent to support collection of a large volume of data. Sample collection and handling routines were well-documented. The laboratory analytical methods, detection limits, and grade assay limits are suited to the style and grade of mineralization. The QA/QC methods enabled assessment of sample security, assay accuracy, and potential for contamination. The QP reviewed sample collection and handling procedures, laboratory analytical methods, QA/QC methods, and QA/QC program results and considers these methods are adequate to support the current Mineral Resource Estimate.

 

 

Prior to Coeur Mining’s acquisition, Las Chispas Operations developed an extensive dataset that is saved and managed using Geospark™ management software. The QPs reviewed the data compilation and audited the Geospark™ database. The QPs completed verification of the Las Chispas Operation databases for gold and silver by comparison of the database entries against assay certificates in comma-separated values (.CSV) and Excel (.XLS) file format, obtained directly from ALS Webtrieve™ and SGS QLab. Assay data were previously verified for five separate datasets: Las Chispas, Las Chispas Underground, Babicanora Underground, William Tell Underground, and Babi Vista. Further verification of the Las Chispas assay data for gold and silver was undertaken by the QPs in December 2024 for the Las Chispas definition and exploration drilling and surface chip-channel data. Very few minor errors were encountered in the data during the December 2024 verification process.

 

The QPs also validated the Mineral Resource database in GEMS™ by checking for inconsistencies in analytical units, duplicate entries, interval, length or distance values less than or equal to zero, blank or zero-value assay results, out-of-sequence intervals, intervals or distances greater than the reported drill hole length, inappropriate collar locations, survey, and missing interval and coordinate fields. A few errors were identified and corrected in the database.

 

The QPs consider the database provided to be reliable and do not consider the few minor discrepancies encountered during the verification process to be of material impact to the data supporting the Mineral Resource Estimate.

 

Site visits and independent sampling programs for assay data verification were completed in March 2022 and December 2024. The assay results for the independent site visit samples match closely to the Las Chispas Operations data for both gold and silver, and the QPs consider the due diligence results to be acceptable.

 

Based on the evaluation of the QA/QC program undertaken previously by Las Chispas Operations personnel, and the QPs due diligence sampling and database verification, it is the QPs’ opinion that the data are robust and suitable for use in the current Mineral Resource Estimate.

 

 

Mineral deposits in the Las Chispas district are classified as gold and silver, low-to intermediate sulphidation epithermal systems, of many deposits in northeastern Sonora and are mined using variations of longhole stoping and cut and fill mining methods via several access drifts and ramps. Ore is processed through a primary jaw crusher, SAG mill in closed circuit with hydrocyclones, cyanide leaching, Merrill-Crowe metal recovery, and tailings filtration. Following startup, the Las Chispas Operation adopted a strategy that involves a whole ore leach at ~2,000 mg/L CN with the flotation and concentrate leach circuits bypassed. Operating data from the whole ore leach is achieving throughput and recoveries at or above flotation and concentrate leach testwork values on similar material presented in the 2021 FS Report.

 

The current operating strategy is providing the best economic value with gold and silver recoveries ranging from 91% to 99% and 95% to 99% with weighted averages of 98% and 98%, respectively.

 

 

The purpose of this Technical Report Summary section is to present the 2024 Mineral Resource Estimate with drilling and underground sampling programs as of October 31, 2024. This Mineral Resource Estimate includes in-situ narrow vein gold and silver mineralization at the Babicanora and Las Chispas Areas.

 

The Mineral Resources Estimate presented herein is reported in accordance with S-K 1300. Confidence in the estimate of an Inferred Mineral Resource is insufficient to allow the meaningful application of technical and economic parameters or to enable an evaluation of economic viability worthy of public disclosure. Mineral Resources may be affected by further infill and exploration drilling that may result in increases or decreases in subsequent Mineral Resource Estimates. Mineral Resources in this estimate are stated exclusive of the Mineral Reserves stated in Section 12.

 

This Mineral Resource Estimate was undertaken with Leapfrog™ Geo software by Las Chispas Operations, and was reviewed and accepted by Yungang Wu, P.Geo. and Eugene Puritch, P.Eng., FEC, CET of P&E Mining Consultants Inc. (P&E) of Brampton, Ontario. Messrs. Wu and Puritch are independent of Coeur Mining as defined in S-K 1300.

 

The effective date of this Mineral Resource Estimate is December 31, 2024.

 

The database supporting this Mineral Resource Estimate consisted of surface drill holes, underground drill holes and underground channel and chip samples for the in-situ narrow veins in both the Babicanora and Las Chispas Areas. All drill hole survey and assay values are expressed in metric units, with grid coordinates reported using the WGS84, zone 12N UTM system.

 

The mineralized vein wireframes were interpreted and constructed by Las Chispas Operations using Seequent Limited Leapfrog^TM® Geo and the QPs reviewed the vein models. Some adjustments to the wireframes were made as a result of the reviews, and the QPs consider the wireframes to reasonably represent the assay data and are suitable for Mineral Resource estimation.

 

A total of 76 unclipped wireframes (50 in Babicanora area and 26 in Las Chispas area) were developed to represent the mineralized veins and splays. The “unclipped” solids were clipped to include mineralized areas with ≥150 g/t AgEq (where AgEq = Ag g/t + (Au g/t * 79.51)). Minimum mining width was not applied, and the mineralized vein wireframe is considered to be undiluted. The clipped wireframes were used as constraining boundaries during Mineral Resource estimation, for rock coding, statistical analysis, and compositing limits.

 

A topographical surface was provided by Las Chispas Operations. All mineralized veins were clipped and removed above that surface. The wireframes of mined areas were created by Las Chispas Operations. Block model volumes captured within the mined depletion wireframe model were excluded from the Mineral Resource Estimate.

 

Due to the nature of the narrow veins and in order to regularize the assay sampling intervals for grade interpolation, a 0.5 m compositing length was selected for the drill hole intervals that fell within the constraints of the above-mentioned vein wireframes. Non-assayed intervals and below detection limit assays were set to 0.001 g/t gold and silver. If the last composite interval was <0.25 m, the composite length was adjusted to make all composite interval lengths of the vein intercept equal. The constrained composite data were extracted to a point area file for grade capping analyses.

 

Grade capping and high-grade transition analyses were undertaken on the 0.5 m composite values in the database within the constraining wireframes to control possible bias resulting from erratic high-grade composites in the database, and to maintain the high-grade local variation. The high-grade transition consists of a restrictive search ellipse and a maximum limiting composite value.

 

Log-probability plots for gold and silver composites were generated by Las Chispas Operations for each mineralized vein. The drill hole and channel sample composites were analyzed separately for each vein.

 

Variography analyses were performed by the Las Chispas Operations using the gold and silver composites within each individual vein wireframe, as a guide to determining a grade interpolation search distance and ellipse orientation strategy.

 

Continuity ellipses based on the observed ranges were subsequently generated and utilized as the basis for grade estimation search ranges, distance weighting calculations and Mineral Resource classification criteria.

 

A total of 53,597 bulk density measurements were collected on site from exploration drill core by Las Chispas Operations using the water immersion method. The measurements tested various mineralized and non-mineralized material types at 20 m down-hole intervals. Where rock material was highly fragmented or strongly clay altered, samples were not collected. The bulk density ranged from 1.90 to 3.50 t/m³ with a mean value of 2.55 t/m³.

 

The block models were constructed by Las Chispas Operations using Leapfrog™® Geo software’s Edge extension. The QPs reviewed and verified the Leapfrog^TM® block models by comparing to the block models interpolated with GEOVIA GEMS™ software for the main veins (more than 80% of overall contained AgEq oz were rerun). The model reviews were discussed between Las Chispas Operations and the QPs during the course of this Mineral Resource Estimate. A few minor changes were made due to the model review. Each block model consists of separate model attributes for estimated gold and silver grades, rock type (mineralized domains), bulk density, AgEq value, and classification.

 

The gold and silver grade values were interpolated into the grade blocks using inverse distance weighting to the third power (ID3). Multiple passes were executed for the grade interpolation to progressively capture the sample points, to avoid over-smoothing and preserve local grade variability. The search ellipse direction and range are variable for each vein based on its variogram performance. A variable orientation search was utilized for all the main veins. The high-grade transition was utilized for the grade interpolation in order to mitigate the high-grade influence.

 

The Mineral Resource was classified as Measured, Indicated, and Inferred based on the geological interpretation, variogram performance and drill hole spacing.

 

A Measured Mineral Resource was classified for the Babicanora underground sampled area only with a 10 m range extended up and down dip from areas with underground in-vein development samples and interpolated with both underground channel and chip samples and drill holes within this area.

 

Indicated Mineral Resources were classified for the blocks interpolated with the Pass 1 in Table 11-10 used at least two drill holes within a 50 m mean distance.

 

Inferred Mineral Resources were classified for all remaining grade blocks within the mineralized veins

 

Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability.

 

The following parameters were used to calculate the AgEq cut-off values that determine the underground mining potentially economic portions of the constrained mineralization:

 

 

 

 

 

 

The AgEq cut-off value of the underground Mineral Resource is calculated as follows:

 

 

Table 1‑1:          Summary of Gold and Silver Measured, Indicated and Inferred Mineral Resource Statement as at December 31, 2024 (Based on US$2,100/oz gold price and US$27/oz silver price)^(1-10)

 

Notes: 1 The estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues. 2 The Inferred Mineral Resource in this estimate has a lower level of confidence than that applied to an Indicated Mineral Resource and must not be converted to a Mineral Reserve. It can be reasonably expected that the majority of the Inferred Mineral Resource could be upgraded to an Indicated Mineral Resource with continued exploration. 3 The Mineral Resource is estimated using Subpart 229.1300 – Disclosure by Registrants Engaged in Mining Operations. 4 Mined areas as of December 31, 2024, were depleted from the wireframes and block models. 5 AgEq is based on Ag:Au ratio of 79.51:1 calculated using approximately $2,100/oz Au and $27/oz Ag, with average metallurgical recoveries of 98% for Au and Ag with 99.9% payable for both Au and Ag. 6 Mineral Resources are exclusive of Mineral Reserves. 7 All numbers are rounded. 8 The cut-off grade (COG) used for in-situ Mineral Resources is 150 g/t AgEq calculated from $55/tonne mining cost, $45/tonne process costs and $27/tonne G&A cost. 9 The point at reference for the mineral estimate is its in-situ location in the mine. 10 Mineral Resources are 100% wholly-owned and attributable to the Company.

 

 

1.11.1

Estimation Methodology

 

Mineral reserves were converted from measured and indicated mineral resources. Inferred mineral resources were set to waste. The mine plans assume underground mining methods including longitudinal longhole open stoping, cut and fill, and resuing, using trackless equipment and a combination of Cemented Rock Fill (CRF) and Unconsolidated Rock Fill (URF) for backfill. Target mining rates are 1,250 t/d initially, increasing to 1,500 t/d for the peak during LOM.

 

Deswik mine planning software was used for the mine design, 3D modeling, and interrogation of the 3D mining model against the block model. The surveyed “as-built” mining excavations were depleted from the designed solids and the resource block model. Mining, geotechnical, and hydrological factors were considered in the estimation of the mineral reserves, including the application of dilution and ore recovery factors.

 

Mining excavations (stopes and ore development) were designed to include mineralized material above the cut-off grade. These excavations were then assessed for economic viability. In addition to the mining cut-off grade, an incremental cut-off grade (excluding the mining cost) was calculated to classify mineralized material mined as a result of essential development to access higher-grade mining areas. Waste and mineralized material below the incremental cut-off will be disposed of on surface in waste rock storage facilities (WRSFs) or will be used underground as backfill.

 

Silver equivalent cut-off grades were calculated for the deposits, with mineral reserves estimated and reported above this cut-off. Silver equivalent grades were calculated using the following formula:

 

 

where AgEq, Ag and Au are the silver equivalent grade, silver grade, and gold grade, respectively, in g / tonne.

 

All mineral reserves are reported using an average silver equivalent cut-off grade of 250 g/tonne, and an incremental cut-off grade of 154 g/tonne AgEq for longhole, 196 g/tonne AgEq for cut and fill, 306 g/tonne AgEq for resue, and 62 g/tonne AgEq for development. Mining dilution assumes 5% for development, 1 meter to 1.5 meters of Equivalent Linear Overbreak Slough (ELOS) (0.5 m – 1.0 m of hanging wall and 0.25 m – 0.5 m of footwall dilution) depending on geotechnical conditions in each longhole stoping location , 0.2 meter ELOS (0.1 m of hangingwall and 0.1 m of footwall dilution) for cut and fill, 0.4 meter ELOS (0.2 m of hanging wall and 0.2 m of footwall dilution), 3% waste volume was added for backfill dilution; mining loss of 2% for development and 5% for stoping was applied, additional losses have been included to account for the required pillars in uphole stopes that cannot be filled.

 

The silver and gold prices used in reserve estimation are based on analysis of three-year rolling averages, long-term consensus pricing, and benchmarks to pricing used by industry peers over the past year. The silver price forecast for the Mineral Reserve Estimate is US$23.50 / oz and the gold price forecast is US$1,800 / oz. The QP considers these prices to be reasonable.

 

1.11.2

Mineral Reserve Statement

 

Mineral reserves are reported using the mineral reserve definitions set out in S-K 1300. The reference point for the Mineral Reserve Estimate is the point of delivery to the process plant. Mineral reserves are reported in Table 1-1 and  Table 1-2 are current as of December 31, 2024. Estimates are reported on a 100% ownership basis.

 

The Qualified Person for the estimate is Mr. Joseph Wallick, P.Eng, a Coeur employee.

 

Table 1‑2:          Summary of Gold and Silver Proven and Probable Mineral Reserve Statement as at December 31, 2024 (based on US$1,800/oz gold price and US$20/oz silver price) ^(1-4)

 

 

1.11.3

Factors that May Affect the Mineral Reserve Estimate

 

Factors that may affect the Mineral Reserve Estimates include: metal price and exchange rate assumptions; changes to the assumptions used to generate the gold equivalent cut-off grade; changes in local interpretations of mineralization geometry and continuity of mineralized zones; changes to geological and mineralization shape and geological and grade continuity assumptions; density and domain assignments; changes to geotechnical, mining and metallurgical recovery assumptions; changes to the input and design parameter assumptions supporting for the mineable shapes constraining the estimates, including dilution forecasts; and assumptions as to the continued ability to access the site, retain mineral and surface rights titles, maintain environment and other regulatory permits, and maintain the social license to operate.

 

 

The Babicanora and Las Chispas mines use conventional underground mining methods and conventional equipment. The overall production rate peaks at 1,500 t/d. Historical mining began in the area as early as the 1640’s, and Silvercrest took ownership of the property in 2015, and underground mining, which is ongoing, started in 2022. Final design outlines for each of these mines can be found in Chapter 12.

 

Depending on the deposit, rock mass quality is variable from Poor to Good. Modifications based on variability and updated geotechnical models were made as the mines develops. The Las Chispas technical services department maintains a Ground Control Management Plan that is overseen by the technical services department that is updated annually and provides mine personnel with operating, monitoring, and quality control/assurance guidance. The Ground Control Management Plan specifies ground support standards and identifies where and how they are applied in the mines.

 

Permeability of the volcanic rock units in all mines is low to very low. Persistent inflows are generally from larger fault structures where flows increase and decrease seasonally because of connections to the surface. Increases in persistent inflows currently are directly related to opening new developments laterally or ramping to lower levels. Water management consists of sumps and pumps, with water pumped to a water treatment plant on surface.

 

Primary access to the Babicanora mine is from surface via two ramps. The Santa Rosa and Babicanora Central portals can handle the proposed trucking fleet and will also be used as intake flows for the primary ventilation circuit

 

Babicanora contains mineralized zones along a strike length of 2,600 m and a depth of 450 m. The mineralized zones are varying in dip and thickness both along strike and at depth. The Babicanora mine includes the following veins of mineralization, the Babicanora Norte (BAN) extends furthest to the north and the El Muerto (EM) vein extends the deepest, with the Granaditas (GRA) vein extending furthest south. Additional veins include Babicanora Vista (BAV), Babicanora Main (BAM), Babicanora Sur (BAS) and Babicanora Central (BAC). While all geometries are suitably extracted using the longitudinal longhole stoping method, particular areas in the BAC vein have been selected for cut and fill mining due to geotechnical considerations. Additionally, resue mining sees limited use in the BAC, BAN, BAV, and EM veins, to minimize dilution in high-grade narrow veins.

 

Las Chispas contains mineralized zones along a strike length of 900 m and a depth of 300 m. The mineralized zones vary in dip and thickness both along strike and at depth. The Las Chispas mine includes the following veins of mineralization, the William Tell (WT) vein extends furthest to the north, with the Las Chispas (LC) vein extending furthest south and the deepest. Additional veins include Giovanni (GIO), Gio Mini (GIOM), Luigi (LUI), and Luigi Footwall (LFW). Mining methods and development sizes are similar to Babicanora, with only the longhole stoping and resue methods being utilized in Las Chispas for production. Backfill is a combination of cemented rock fill and unconsolidated rock fill.

 

Underground maintenance facilities in Babicanora support field and preventative maintenance activities. Primary maintenance is conducted in joint facilities located on surface and a large main facility located near the Las Chispas office and plant site. Surface magazines support Babicanora and Las Chispas.

 

The Las Chispas Operations has a seven-year mine life remaining overall..

 

 

Based on the operating results, Ausenco’s design for treatment of a variety of feed grades is meeting or exceeding design expectations. The Process Plant is located at the mine site and receives blended feed material from several different mineralized veins. The key process design criteria for the plant are:

 

 

 

 

The current operating strategy has the flotation, concentrate leach and cyanide detoxification circuit typically by-passed. The Process Plant is using the bulk leach circuit to perform a whole ore leach at ~2,000 ppm CN. Overall recoveries remain high, and weak acid dissociable cyanide (CN_wad) levels in filtered tailings seepage ponds are well below International Management Cyanide Code (ICMC) limits. The cyanide detoxification circuit has been modified to process solution or slurry and is operated as required to maintain seepage pond concentrations below the ICMC limit. Figure 1‑1 presents an overall process flow diagram of the Process Plant as currently operated.

 

The total operating design power for the Process Plant is between 3.8 and 4.6 MW depending on which circuits are being operated. Provisions were made for raw water to be supplied from the underground mine, the fresh water (storm) pond, the Sonora Valley, or any combination there of pending availability and requirements. Wherever possible in the Process Plant, process water or barren solution is used to minimize freshwater consumption. Potable water is sourced from the sediment-free water in the raw water tanks and treated prior to distribution or shipped to site. Process Plant consumables for current operations include quick lime, sodium cyanide, lead nitrate, oxygen, flocculants, coagulant, diatomaceous earth, zinc powder, copper sulphate, anti-scalant, and flux.

 

Figure 1‑1:

Overall Process Design

 

 

Source: Ausenco, 2023

 

 

1.14.1

Introduction

 

Infrastructure existing for the mining and processing operations include can be seen in the site layout in Figure 1‑2.