The latest results continue to demonstrate the potential for significant near-mine resource expansion at Tahuehueto, with high-grade mineralization intersected across the Creston, Perdido veins and specifically at the Catorce Zone, an under-drilled area interpreted to represent a southern extension of the Creston Vein system. At Catorce, drilling has resumed for the first time since 2008, with the first surface hole returning 9.9 metres of 5.39 g/t AuEq, including 1.0 metre of 27.56 g/t AuEq, highlighting the potential of this underexplored vein system.
Highlights
- High-grade results from the first surface drillhole at the Catorce Zone since 2008:
- 9.9 metres ("m") of 5.39 g/t AuEq** (3.63 g/t Au, 70.14 g/t Ag, 0.02% Cu, 1.69% Pb, 5.63% Zn) in hole DDH26-RCE-01 including 1.0 m of 27.56 g/t AuEq (21.10 g/t Au, 58.50 g/t Ag, 0.09% Cu, 3.93% Pb, 38.25% Zn)
- The Catorce Zone is located approximately 250 m from existing underground development and is interpreted to be a southern extension of the Creston Vein within an area of structural complexity (Figure 1). This area was targeted by Luca with 7 holes totalling ~1,500 m of diamond drilling in this new exploration campaign.
- Continued high-grade intercepts from the Creston Vein, including:
- 6.2 m of 6.37 g/t AuEq (3.68 g/t Au, 153.91 g/t Ag, 0.91% Cu, 1.17% Pb and 1.15% Zn) in hole DDH26-248 including 1.1 m of 20.60 g/t AuEq (12.00 g/t Au, 563.00 g/t Ag, 2.51% Cu, 3.51% Pb, 0.86% Zn) within a broader interval of 2.9 m of 11.83 g/t AuEq (7.29 g/t Au, 281.12 g/t Ag, 1.46% Cu, 1.70% Pb, 1.06% Zn)
- 3.4 m of 4.77 g/t AuEq (2.00 g/t Au, 190.24 g/t Ag, 0.16% Cu, 1.76% Pb and 2.77% Zn) in hole DDH26-249 including 0.8 m of 11.67 g/t AuEq (4.65 g/t Au, 608.00 g/t Ag, 0.30% Cu, 1.78% Pb and 0.51% Zn)
- 1.3 m of 13.53 g/t AuEq (2.80 g/t Au, 538.23 g/t Ag, 6.17% Cu, 0.13% Pb and 0.04% Zn) and a secondary intersection of 1.3 m of 4.50 g/t AuEq (0.76 g/t Au, 247.86 g/t Ag, 1.32% Cu, 0.18% Pb and 0.06% Zn) in hole DDH26-250
- Drilling has confirmed the continuity of high-grade mineralization in previously untested areas located 20 to 35 m below Level 20, with all 14 drillholes completed in this newly identified area intersecting the Creston Vein, further validating Luca's geological model and demonstrating the potential to expand mineralization at depth
- The new intercepts exceed current mined grades and widths and occur within development distance of existing underground infrastructure, supporting potential integration into the near-term mine plan
- Confirmed mineralization at the Perdido Vein in close proximity to current mining faces through the ongoing Termite drill program:
- 0.9 m of 7.60 g/t AuEq (7.03 g/t Au, 32.70 g/t Ag, 0.08% Cu, 0.48% Pb and 0.64% Zn) in hole TRT26-07
- Two contracted diamond drill rigs are currently on site and a third surface rig is currently en route to site. A Luca owned and operated underground rig continues to define mineralization identified in the near-term mine plan.
"The latest results continue to reinforce our view that Tahuehueto has significant expansion potential beyond the current resource areas," stated Paul D. Gray, VP Exploration. "At Creston, all 14 drillholes targeting the breccia zone below Level 20 have intersected the vein, demonstrating excellent continuity and providing further confidence in the potential to expand the structure at depth.
"Equally exciting is the first surface drilling from the Catorce Zone since 2008, where the first hole returned 9.9 metres of 5.39 g/t AuEq, including 1.0 metre of 27.56 g/t AuEq. This strong result from a previously underexplored area supports our view of the unrealized exploration potential across the property, which we continue to uncover with additional Catorce assays pending and ongoing drilling across multiple target areas."
Drill Results Summary
Drillholes DDH26-SU-17 through DDH26-SU-20 targeted a previously untested zone approximately 30-40 metres below active mine workings on Level 23 and along strike from Luca's successful Phase 1 2024-2025 underground drill program and more recent drilling efforts (See Company News Releases Dated February 20, 2025, March 5, May 5, and July 7, 2026) and expanded upon these previously identified high-grade breccia zones.
Drillhole DDH26-247 through DDH26-255 were collared underground on Level 20 of the Tahuehueto gold-silver mine and targeted the Creston Vein in previously undrilled areas approximately 30 m below current workings. These holes were designed to expand upon and infill to a minimum 25 m spacing this newly defined mineralized breccia shoot first identified by Luca in 2026 (See Company News Release dated July 7, 2026). All these drillholes intersected the Creston Vein.
Drillhole DDH26-RCE-01 targeted mineralization previously identified within the Catorce Zone, a known, but under-drilled Tahuehueto mineralized zone that is interpreted to be a southern extension of the Creston Vein System and has not seen any exploration efforts since 2008.
To date, Luca has completed 62 underground holes for 11,182 m and 33 surface holes for 6,224 m using "HQ", "NQ" and/or "BQ" sized diamond drill core (Creston, Perdido, El Rey, Catorce and Santiago targets).
Key Intercepts
Catorce:
DDH26-RCE-01
- 9.9 metres ("m") of 5.39 g/t AuEq** (3.63 g/t Au, 70.14 g/t Ag, 0.02% Cu, 1.69% Pb, 5.63% Zn) from 199.5 m including 1.0 m of 27.56 g/t AuEq (21.10 g/t Au, 58.50 g/t Ag, 0.09% Cu, 3.93% Pb, 38.25% Zn) from 205.4 m
Creston:
DDH26-248
- 6.2 m of 6.37 g/t AuEq (3.68 g/t Au, 153.91 g/t Ag, 0.91% Cu, 1.17% Pb and 1.15% Zn) from 145.1 including 1.1 m of 20.60 g/t AuEq (12.00 g/t Au, 563.00 g/t Ag, 2.51% Cu, 3.51% Pb, 0.86% Zn) within a broader interval of 2.9 m of 11.83 g/t AuEq (7.29 g/t Au, 281.12 g/t Ag, 1.46% Cu, 1.70% Pb, 1.06% Zn)
DDH26-249
- 3.4 m of 4.77 g/t AuEq (2.00 g/t Au, 190.24 g/t Ag, 0.16% Cu, 1.76% Pb and 2.77% Zn) from 134.2 m including 0.8 m of 11.67 g/t AuEq (4.65 g/t Au, 608.00 g/t Ag, 0.30% Cu, 1.78% Pb and 0.51% Zn) from 135.9 m
DDH26-250
- 1.3 m of 13.53 g/t AuEq (2.80 g/t Au, 583.23 g/t Ag, 6.17% Cu, 0.13% Pb and 0.04% Zn) from 147.6 m and a secondary intersection of 1.3 m of 4.50 g/t AuEq (0.76 g/t Au, 247.86 g/t Ag, 1.32% Cu, 0.18% Pb and 0.06% Zn) from 134.4 m
DDH26-SU-17
- 0.8 m of 13.85 g/t AuEq (12.30 g/t Au, 42.20 g/t Ag, 0.16% Cu, 0.37% Pb and 6.77% Zn) from 122.0 m and a secondary intersection of 0.8 m of 2.05 g/t AuEq (0.53 g/t Au, 47.30 g/t Ag, 0.28% Cu, 2.36% Pb and 3.57% Zn) from 132.8 m
Production Verification Drillholes
As part of the Tahuehueto exploration program a Luca owned and operated Termite drill rig capable of drilling "BQ" sized drill core up to 100 m in length has been added to bolster near underground workings verification and mineral definition. Drill core from this drill rig is handled by the Tahuehueto exploration department and treated the same as exploration drill core (processing, logging and sampling) and is now being utilized to more accurately define the mineralized zones anticipated to be part of the near-term mine plan objectives. Drillholes TRT26-07 and TRT26-08 were drilled from Level 12 of the Tahuehueto mine and targeted the Perdido vein in areas that are scheduled to be mined during H2 2026 – H1 2027.
TRT26-07
- 0.9 m of 7.60 g/t AuEq (7.03 g/t Au, 32.70 g/t Ag, 0.08% Cu, 0.48% Pb and 0.64% Zn) in hole TRT26-07 from 42.2 m
True widths are estimated to be approximately 85-90% of drilled intervals.
Figures 1-11 present the location of the drillholes with assay results and Tables 1 and 2 provide summary analytical results and drill collar details, respectively.
About 2026 Tahuehueto Exploration Program
The Tahuehueto property comprises a large epithermal gold-silver vein system with approximately 11 kilometres of known vein strike length and numerous mineralized structures. Mineralization remains open along strike and at depth across most modeled Mineral Resource areas. The current campaigns represent the first substantive exploration drilling conducted on the property in more than 12 years, and the first since the addition of key concessions to the land package (See Company News Release dated August 28, 2025).
Luca's 2026 exploration program builds on the success of the 2025 campaign. The program is designed to expand known mineral resources, adding near-term mineable material and defining the vertical and lateral extent of mineralization, as well as to identify additional thick, high-grade breccia zones known to occur within the epithermal vein system, and test multiple underexplored vein systems.
In addition to the four veins that currently support the mineral resource, at least 14 additional prospective veins have been documented within the concession area with potential to host epithermal Au-Ag (±Cu-Zn-Pb) mineralization. In several cases, these targets may represent extensions of the existing mineralized structures.
Overall, the Company has identified more than 11 km of prospective vein structures along strike, compared to approximately 4.5 km of mineralized veins incorporated into the current mineral resource model, highlighting significant exploration upside across the property.
Assay Tables and Collar Locations
Table 1: Highlighted Diamond Drill Assay Results from DDH26-247 through DDH26-255, DDH26-SU-17 through DDH26-SU-20, TRT26-07 through TRT26-08 and DDH26-RCE-01
Table 2: Drill Collar Locations and Details for Released Results
About Luca Mining Corp.
Luca Mining (TSX-V: LUCA, OTCQX: LUCMF, Frankfurt: Z68) is a diversified Canadian mining company with two 100%-owned producing mines within the prolific Sierra Madre mineralized belt in Mexico which hosts numerous producing and historical mines along its trend.