Altoro Metals (ASX:ARO) has completed three holes at its Guajaraz Zinc-Lead-Silver Project in central Spain. Drilling has intersected brown sphalerite veinlets that confirm zinc sulphide mineralisation at depth.
The maiden 1,400m diamond drilling program is designed to test carbonate-hosted replacement-style zinc mineralisation. It will also test subparallel structures associated with the historical La Unión mine.
Altoro generated the targets through geological mapping, historical mine data, and 8.5 line kilometres of deep ground-penetrating radar (DGPR) surveying.
Holes G-02, G-03, and G-04 are complete, with G-01 and G-05 in progress.
G-03 intersected veinlets of brown sphalerite, though the company cautions the significance cannot be assessed until analytical results are available.
Hole G-04 was stopped at 53.35m after reaching its first target zone, allowing the rig to relocate promptly to G-05.
Meanwhile, G-05 tested the western side of the historical system, intersecting substantial metasedimentary rocks before entering gneissic rock with multiple zones of strong hydrothermal alteration and low-grade mineralisation.
The company notes that much of the 200m drilled so far consists of strong bleaching, sericitic and chloritic alteration, and quartz veining, with minor zinc and lead mineralisation observed.
Altoro has updated the drilling strategy as it receives results, prioritising zones with the highest potential for grade and tonnage. The company also cites the London Metal Exchange zinc price recently surpassing US$4,000 ($5,700) per tonne.
Core is being systematically logged and sampled, with assay results expected within four to six weeks. Altoro is progressing its application for a three-year extension of the Guajaraz exploration permit.
Once G-01 is complete, one drill rig will mobilise to the company’s flagship Novales-Udías Project in Cantabria for the next phase of surface drilling.
The historical La Unión system extends to about 280m depth across multiple levels and produced lead-zinc sulphide mineralisation with reported silver credits.
Altoro Metals is an Australian explorer focused on zinc and polymetallic projects across Spain and Australia.
Write to JC Villarba at Mining.com.au
Images: Altoro Metals
