First Majestic Silver Corp. announced the discovery of a significant new, vein-hosted gold and silver mineralized system at its Santa Elena property in Sonora, Mexico. This new high-grade discovery, the Navidad vein system ("Navidad"), was made at depth adjacent to the Company's 100%-owned and currently producing Ermitaño mine.

DRILLING HIGHLIGHTS The high-grade, mineralized composite sample intervals from the six drillholes intersecting the Navidad vein system are as follows: Drilling Highlights for the Navidad Vein System:EW-24-364: 8.15 g/t Au and 427 g/t Ag over 4.78 metres ("m") true thickness (Navidad Vein), EW-24-370: 10.13 g/t Au and 86 g/t Ag over 4.42 m true thickness (Navidad Vein), EW-24-370: 5.65 g/t Au and 46 g/t Ag over 5.75 m true thickness, EW-24-368: 54.93 g/t Au and 399 g/t Ag over 1.82 m true thickness (Navidad Vein), EW-23-359: 3.27 g/t Au and 39 g/t Ag over 2.46 m true thickness (Navidad Vein), EW-23-360: 5.83 g/t Au and 146 g/t Ag over 1.53 m true thickness, EW-23-360: 4.75 g/t Au and 68 g/t Ag over 1.91 m true thickness, EW-23-360: 4.06 g/t Au and 77 g/t Ag over 2.09 m true thickness, EW-23-360: 3.48 g/t Au and 74 g/t Ag over 2.39 m true thickness (Navidad Vein), EW-24-366: 1.40 g/t Au and 124 g/t Ag over 2.85 m true thickness (Navidad Vein). An exploratory program of deep drill holes tested favourable host rocks located at depth and to the west of a regional fault that extends to the west side of the resource deposit for the Ermitaño mine. The drilling intersected a set of quartz veins with visible silver sulfides and banded quartz textures locally; the most prominent vein intersected has been named Navidad.

An additional mineralized vein located in the Navidad vein hanging wall ("HW vein") was also intersected along with quartz stockwork and sheeted veins, representing a geologic configuration similar to the Ermitaño vein system. To date, seven drill holes have been completed to test the Navidad discovery; six of these holes intersected significant vein-hosted gold and silver mineralization. The closest drill hole intercept to the Ermitaño mine is located approximately 500 m southwest and 750 m below existing mine development.

The Navidad vein system has an apparent strike to the northeast and dips at a moderate to low angle to the northwest. The intersections from the six drill holes currently outline vein-hosted gold and silver mineralization with an apparent strike length continuity of 750 m and a dip continuity of 225 m (minimum distances between drill hole intersections). The average thickness of the Navidad vein ranges from 1.8 to 5.0 m and adjacent vein thickness ranges from 1.5 to 6 m. The last two drill holes to intersect the Navidad system, EW-24-368 and EW-24-370, are spaced 750 m apart and produced the two highest grade vein intercepts to date.

Drill hole EW-24-368 intersected the Navidad vein and yielded 54.93 g/t Au and 399 g/t Ag over 1.82 m (true thickness). Drill hole EW-24-370 intersected two, thick, banded quartz veins, the Navidad vein and the HW vein, with high-grade gold and silver mineralization spaced 190 m apart downhole. These two vein intersections yielded 5.65 g/t Au and 46 g/t Ag over 5.75 m and 10.13 g/t Au and 86 g/t Ag over 4.42 m (true thickness).

The full extent and geometry of the Navidad gold and silver vein system are not yet known, and the exploration potential is open in all directions. Additional drill rigs have been reassigned to explore the extent and grade of the Navidad mineralization during 2024. First Majestic's drilling programs follow established Quality Assurance /Quality Control ("QA/QC") insertion protocols with standards, blanks, and duplicates introduced into the sample-stream.

After geological logging, all drill core samples are cut in half. One half of the core is submitted to the laboratory for analysis and the remaining half core is retained on-site for verification and reference purposes or for future metallurgical testing. Core samples were submitted to the SGS laboratory (ISO/IEC 17025:2017).

At SGS, gold is analyzed by 30 g or 50 g fire assay atomic absorption finish (GE-FAA30V5, GE-FAA50V5). Results above 10 g/t gold are analyzed by 30 g or 50 g fire assay gravimetric finish (GO-FAG30V, GO-FAG50V). Silver is analyzed by 3-acid digest atomic absorption finish (GE-AAS33E50).

Results above 100 g/t silver are analyzed by 30 g or 50 g fire assay gravimetric finish (GO-FAG37V, GO-FAG57V).