A new geophysical survey at EV Resources’ Los Lirios project in Mexico reveals extensive sulphide anomalies and a structural fault network, significantly expanding the exploration footprint and sharpening drill targets ahead of a maiden resource estimate.
- CSAMT survey identifies deep sulphide feeder zone near existing drilling
- Large, open low-resistivity anomaly to southeast signals scale potential
- Structural fault network offers precise vectoring for high-grade mineralisation
- Phase 2 drilling planned to test new targets and define maiden JORC resource
- Ongoing legal issues cloud mining concession status at Los Lirios 1
Geophysics Expands Los Lirios Mineralisation Footprint
EV Resources (ASX:EVR) has substantially broadened the known scale of its Los Lirios Antimony Project in Oaxaca, Mexico, following a Controlled Source Audio-frequency MagnetoTelluric (CSAMT) geophysical survey. The survey pinpointed three high-priority targets, including a deep, structurally controlled sulphide feeder zone adjacent to prior drilling and a vast, untested low-resistivity anomaly to the southeast that could represent a large-scale sulphide replacement system.
These findings suggest the mineralised system extends well beyond the Phase 1 drilling boundaries, underscoring a materially larger footprint than previously recognised. The low-resistivity anomalies, interpreted as zones of potential sulphide enrichment, contrast sharply with the high resistivity of the surrounding limestone and gypsum host rocks, offering compelling new vectors for exploration.
Structural Fault Network Provides Targeting Framework
Mapping of vertical fault lineaments revealed a network of sub-parallel structures that align with known feeder faults San Elias and San Miguel. This structural framework is critical, as these faults likely channelled mineralising hydrothermal fluids into receptive limestone units, forming the carbonate replacement deposits (CRDs) hosting antimony mineralisation.
Notably, pit wall channel sampling shows antimony grades peak near these faults and diminish laterally, reinforcing the importance of targeting intersections within this fault network. EV Resources intends to leverage this vectoring tool to focus its upcoming Phase 2 drill program on areas with the highest potential for high-grade mineralisation.
Phase 2 Drilling to Focus on New and Known Targets
Field verification is underway to correlate the geophysical anomalies with surface geology and geochemistry, refining drill pad locations ahead of the next drilling campaign. The Phase 2 program aims to expand the mineralisation footprint by testing the large southeast anomaly and the inferred sulphide feeder zone, while also densifying drilling over known zones to underpin a maiden JORC Mineral Resource Estimate (MRE).
EV Resources’ Managing Director Mike Brown described the survey results as "a highly encouraging step forward for the scale potential" of Los Lirios. He emphasised the "clear and aggressive" strategy to rapidly advance towards resource definition by testing these structurally controlled corridors where fluid interaction is optimised.
Legal and Operational Challenges Remain
Despite the technical progress, the Los Lirios 1 mining concession is currently subject to ongoing administrative and judicial proceedings following cancellation attempts by Mexican authorities. EV Resources is pursuing reinstatement with legal support, but the process introduces uncertainty around the timeline for exploration and development activities.
Meanwhile, EV Resources continues to advance its broader antimony strategy, including the Tecomatlán Processing Plant refurbishment and feedstock agreements to support near-term production, positioning the company amid tightening global antimony supply.
Bottom Line?
The geophysical survey reshapes Los Lirios’ exploration landscape, but legal hurdles and the need for drilling confirmation mean the path to resource definition remains complex.
Questions in the middle?
- Will Phase 2 drilling confirm the extent and grade implied by the geophysical anomalies?
- How will the ongoing legal dispute over the Los Lirios 1 concession affect project timelines?
- Can EV Resources leverage the structural targeting framework to accelerate high-grade resource delineation?