Andean Silver Limited has announced the discovery of a highly prospective new exploration area at its Cerro Bayo Project in Chile, with surface sampling returning exceptional assay grades of up to 62,663g/t silver equivalent. The Juanita Prospect, located approximately 6km east of the company’s Laguna Verde processing facility, represents a distinct breccia-hosted silver-gold system that differs from typical epithermal vein deposits found elsewhere across the project. The discovery sits outside the company’s existing 136 million ounce silver-equivalent resource base and could represent a significant addition to Andean Silver’s future development pipeline.
Key Points
- Andean Silver Limited (ASX: ASL) has identified the Juanita Prospect, a new silver-gold exploration area at the Cerro Bayo Project in Chile
- Surface rock chip sampling returned bonanza-grade results including 62,663g/t silver equivalent (25,047g/t Ag & 453.2g/t Au), among the highest grades recorded
- The prospect extends over a 2km strike length and features mineralised breccia zones with observed widths up to 18 metres
- Andean is undertaking geological mapping and channel sampling along the Juanita trend ahead of drill testing, with A$53.4m cash available at the end of the March Quarter
New Breccia-Hosted Silver-Gold System Distinct from Company’s Existing Vein-Style Deposits
Andean Silver’s recent exploration work at the Juanita Prospect has identified a mineralisation style that differs fundamentally from the epithermal vein occurrences typically found across the company’s 330 square kilometre mining claim package at Cerro Bayo. The Juanita discovery comprises multiple breccia-hosted silver-gold zones controlled by a steeply west-dipping normal fault that can be traced for over 2km, with structural geometries similar to those hosting major deposits elsewhere across the project. This structural setting, combined with evidence of repeated structural reactivation and multiple mineralising events, suggests the potential for a large and significant silver-gold system rather than isolated vein occurrences.
The geological characteristics of the Juanita system are particularly notable because the high-grade breccia mineralisation comprises multiple hydrothermal and mineralising events developed along several structural controls. The breccias feature multiple mineralising pulses, including older mineralised volcanic host-rock clasts enclosed within a younger hydrothermal breccia matrix that is also strongly mineralised and exhibits variable degrees of silicification. The combination of these geological factors—repeated structural events, multiple mineralising phases, and favourable host lithologies—indicates that Juanita has potential as a distinct mineralisation style worthy of significant exploration investment and resource definition.
Exceptional Surface Sampling Grades Position Juanita as High-Priority Exploration Target
The surface rock chip sampling programme conducted by Andean at the Juanita Prospect has returned exceptional assay results that underscore the high-grade nature of the mineralisation. The highest result recorded 62,663g/t silver equivalent, comprising 25,047g/t silver and 453.2g/t gold, equivalent to 755g/t gold equivalent. A second sample returned 41,489g/t silver equivalent (37,024g/t Ag & 53.8g/t Au), or 500g/t AuEq. Additional samples yielded 16,963g/t AgEq, 15,367g/t AgEq, 15,169g/t AgEq, 13,951g/t AgEq, and 13,680g/t AgEq respectively. These grades represent bonanza-level precious metals content and are substantially higher than typical exploration targets in the region.
The high-grade breccia zones have been observed with widths ranging up to 18 metres, suggesting the potential for significant tonnage to complement the exceptional grades already identified. Notably, individual breccia zones typically range from approximately 1 to 5 metres in width and are characterised by visual subtlety, with only weak textural contrast to surrounding host rocks and consequently little distinctive topographic expression at surface. This feature explains why the Juanita system has remained underexplored for approximately 20 years despite its potential—the subtle surface expression and limited historic drilling have allowed the prospect to remain largely overlooked until recent mapping and sampling programmes brought the high-grade mineralisation to light.
Historic Drilling Results Indicate Juanita System Remains Significantly Underexplored
Limited historic scout drilling conducted up until 2004 intersected portions of the Juanita mineralised system, but geological modelling based on Andean’s data compilation and recent mapping indicates that much of this historic drilling did not effectively test the most prospective portions of the vein-breccia system. The historic drilling programme comprised only 17 holes totalling 1,575 metres, with only five holes and channel samples intersecting parts of the higher-grade system. Despite this sparse drilling, the results were significant: drill hole BJ920 returned 17.1 metres at 194g/t silver equivalent (131g/t Ag & 0.8g/t Au), including 3.3 metres at 897g/t silver equivalent. Drill hole BJ924 returned 8.5 metres at 136g/t silver equivalent, including 2.1 metres at 468g/t silver equivalent (264g/t Ag & 2.5g/t Au).
Historic channel sampling programmes also returned compelling results, including 1.6 metres at 1,209g/t silver equivalent (871g/t Ag & 4.1g/t Au) and 7.2 metres at 296g/t silver equivalent (222g/t Ag & 0.9g/t Au), with the latter including 0.9 metres at 2,114g/t silver equivalent (1,728g/t Ag & 4.7g/t Au). The company’s geological analysis suggests that many historic holes failed to adequately evaluate the interpreted high-grade breccia zones at depth or along the strike extensions of the brecciated structures, leaving the system significantly underexplored and representing a major opportunity for systematic drill testing under modern exploration protocols and interpretation frameworks.
Juanita Prospect Positioned Outside Existing 136-Million-Ounce Silver-Equivalent Resource Base
The Juanita Prospect discovery is particularly significant because it sits outside the company’s existing measured and indicated resources at the Cerro Bayo Project. The Cerro Bayo Project currently hosts total resources of 136 million ounces of silver equivalent, with an additional approximately 100 million ounces mined historically. This substantial existing resource base, combined with the Laguna Verde processing facility located approximately 6km west of the Juanita Prospect, provides Andean with significant infrastructure and operational capability that could be leveraged to develop any future mineral resources defined at Juanita.
The discovery of Juanita represents the third new large exploration area identified outside the existing resources at the Cerro Bayo Project, alongside the Guanaco and Droughtmaster corridors previously identified by the company. This expanding prospect pipeline demonstrates the exploration upside available across Andean’s 330 square kilometre claim package and suggests that the company’s geological team continues to identify new mineralised systems with potential to extend the resource base and support future production growth. The presence of the Laguna Verde facility, with its established processing capability, positions the company favourably to advance any resources defined at Juanita through to potential development without requiring major new infrastructure investment.
Planned Exploration Programme to Define Extent of High-Grade Mineralisation Along 2km Strike Length
Based on the compelling surface sampling and historic drilling results, Andean has initiated a systematic exploration programme designed to further define the extent of high-grade silver-gold mineralisation at Juanita ahead of drilling. The company is undertaking geological mapping and sawn channel sampling along the entire 2km-long Juanita trend to establish a firmer geological and structural understanding of the mineralised system. This surface-based work is designed to identify the most prospective drilling targets and to better understand the lateral and vertical extent of the high-grade breccia zones before committing significant capital to drill testing.
The exploration programme recognises that the mineralised breccia zones feature subtle visual expression and may exhibit little or no distinctive topographic expression at surface, requiring careful geological mapping and sampling to adequately define the system’s geometry and character. The structure has been identified as potentially open to the south for at least approximately 1km, which will be a focus of future exploration activities. By completing surface work ahead of drilling, Andean aims to optimise its drilling programme and ensure that future drill holes are positioned to effectively test the most prospective interpreted high-grade breccia zones at depth and along strike extensions, learning from the limitations of the historic drilling approach that failed to comprehensively test the system.
Strong Cash Position Supports Growth Drilling and Advancement of Cerro Bayo Project Development
Andean Silver reported cash holdings of A$53.4 million at the end of the March Quarter, providing substantial financial resources to fund growth drilling programmes and future feasibility works across the Cerro Bayo Project. This strong liquidity position places the company in a favourable position to advance the Juanita Prospect through exploration and development phases without requiring immediate equity capital raises or debt financing. The availability of capital resources allows management to pursue an aggressive exploration and drilling programme across multiple prospects within the company’s claim package, including the newly identified Juanita Prospect and the previously identified Guanaco and Droughtmaster exploration corridors.
The company’s financial position is supported by its ownership of the Laguna Verde processing facility and its 136-million-ounce silver-equivalent resource base, which provide long-term optionality for future production and cashflow generation. The capital available to fund growth drilling and feasibility studies represents a key strength relative to earlier-stage junior explorers and allows Andean to move methodically through systematic exploration phases designed to build confidence in resource estimates and economic viability before committing to major development capital. The combination of strong cash backing, established infrastructure, and an expanding prospect pipeline positions Andean to create shareholder value through organic exploration success.
Regional Structural Setting and Fault-Hosted Mineralisation Similar to Major Deposits Across Cerro Bayo
The Juanita Prospect is located within a regionally significant NNW to NS trending structural zone controlled by a steeply west-dipping normal fault that hosts NW to NS trending silver-gold breccias and veins. The structural geometries present at Juanita are similar to those that host major deposits across the Cerro Bayo Project, suggesting that the structural controls on mineralisation are well understood and that the geological model underpinning the Juanita discovery has been validated through observation at other deposits within the project area. The north-dipping normal fault system represents a major structural feature capable of hosting significant mineralisation and suggests that Juanita may be one of multiple mineralised systems along this fault trend that warrant exploration.
The fault-hosted nature of the mineralisation, combined with the presence of favourable host lithologies and evidence of multiple mineralising events, provides a robust geological framework for targeting future exploration work. The company’s detailed knowledge of the structural and lithological controls on mineralisation at major deposits such as Laguna Verde, Guanaco, and Droughtmaster has informed the identification of Juanita as a prospective exploration target and supports the geological interpretation that the prospect has potential to host a significant silver-gold system. The regional structural setting places Juanita within a mineral-rich district with a long history of silver and gold production, enhancing the confidence in the exploration model and the potential for economic mineralisation.
Discovery Emerges from Multi-Phase Hydrothermal System with Repeated Structural Reactivation
The Juanita mineralisation system is characterised by evidence of multiple hydrothermal and mineralising events developed along several structural controls, with breccia zones featuring multiple mineralising pulses that have been identified through geological mapping and sampling. The mineralisation appears to represent a polymetallic system with older mineralised volcanic host-rock clasts enclosed within a younger hydrothermal breccia matrix that is also strongly mineralised and exhibits variable degrees of silicification. This multi-phase mineralisation style suggests that the system has experienced multiple episodes of fluid flow and mineral precipitation, potentially creating zones of particularly high-grade mineralisation at the intersection of mineralising phases.
The evidence of repeated structural reactivation and multiple mineralising events is a favourable geological indicator that suggests the Juanita system has the potential to host a large and significant silver-gold breccia mineralised system capable of supporting future resource definition and potential economic extraction. The subtlety of the system’s surface expression—with individual breccia zones exhibiting weak textural contrast to surrounding rocks and limited topographic expression—explains why the prospect remained underexplored for 20 years despite its mineral potential. This discovery demonstrates the value of systematic geological mapping and sampling programmes in identifying overlooked exploration targets and highlights the importance of detailed field-based investigation in evaluating a company’s mineral claim package.
Andean Silver’s Operational Position at Cerro Bayo and Future Exploration Strategy
Andean Silver Limited operates the Cerro Bayo Project in the Chilean Andes, a region with a long and productive history of silver and gold mining. The company’s 330 square kilometre claim package encompasses multiple mineralised systems and hosts total resources of 136 million ounces of silver equivalent, supplemented by the Laguna Verde processing facility that provides established infrastructure for potential future production. The company’s exploration strategy emphasises systematic evaluation of its large claim package to identify new exploration prospects and extend the resource base, as evidenced by the identification of three new large exploration areas—Juanita, Guanaco, and Droughtmaster—outside the existing resource base.
The Juanita discovery represents the outcome of systematic exploration work and demonstrates the company’s capability to identify and evaluate new mineralised systems within its tenement area. The strong cash position, established processing infrastructure, and expanding prospect pipeline position Andean favourably for future growth. Managing Director Matthew Allen commented that Juanita represents a potentially significant silver-gold prospect, with mineralisation that differs from the vein-style deposits common across the company’s tenure, featuring high-grade silver and gold occurring over a substantial strike length and through multiple mineralising events. The next key milestones for the company include completion of geological mapping and channel sampling along the Juanita trend, followed by systematic drill testing designed to evaluate the prospect’s resource potential and advance it toward resource definition.