Exploration Risk Remains as High-Grade Copper Not Repeated in Latest Calais Hole

A Promising Step Forward at Calais

Magmatic Resources Limited has unveiled encouraging results from its ongoing diamond drilling program at the Calais prospect, part of the Myall Farm-in and Joint Venture Agreement (FJVA) with Fortescue Resources Pty Ltd near Narromine, New South Wales. The second deep hole at Calais, FMD0508, drilled to nearly 394 metres, intersected a broad zone of copper and gold mineralisation within an intensely altered diorite host rock.

Notably, the hole returned 11.7 metres grading 0.59 grams per tonne gold and 0.38% zinc starting at 138 metres depth, embedded within a 271-metre magnetite-pyrite-chalcopyrite alteration zone. This mineralised envelope is interpreted as the wallrock of a porphyry system, a style of deposit known for its large-scale copper and gold resources. The presence of an epithermal overprint at upper levels hints at complex mineralising processes that could enhance the prospect’s value.

Context Within the Myall Project and Regional Significance

The Calais prospect lies approximately 2.5 kilometres southwest of Magmatic’s Corvette-Kingswood area, where a maiden Inferred Mineral Resource Estimate of 110 million tonnes at 0.33% copper equivalent was announced in 2023. The Myall Project itself is strategically positioned within the East Lachlan region, a prolific copper-gold province hosting major operations such as the Northparkes and Cowal mines.

Under the FJVA signed in March 2024, Fortescue is committed to investing up to $14 million over six years to earn up to a 75% interest in the project, underscoring the strategic importance of the Myall tenement. Fortescue’s involvement brings significant technical expertise and financial backing, accelerating exploration efforts.

Interpreting the Drilling Results and Next Steps

While the high-grade copper intercept from the earlier hole FMD0504 was not replicated in FMD0508, the latter’s broad alteration and gold-zinc mineralisation suggest a sizeable and complex system remains to be delineated. Magmatic’s Managing Director, David Richardson, highlighted the significance of intersecting gold-copper mineralisation at this early stage, describing it as a promising second exploration front within the Myall Project.

Further drilling is planned to better understand the structural controls and to vector towards the core of the porphyry system. Assay results from other regional targets such as Monaro and Sandman are awaited, which will provide additional insights into the broader mineral potential of the Myall JV area.

Technical Rigor and Exploration Integrity

The drilling program employs industry-standard diamond core techniques with rigorous sampling, logging, and assay protocols overseen by qualified geologists. Assays were conducted by ALS Laboratories using near-total digest methods, ensuring reliable and representative data. The company adheres to the JORC Code standards for reporting, with competent persons confirming the validity of the results.

Magmatic and Fortescue’s collaborative approach combines detailed geophysical and geochemical modelling with systematic drilling, aiming to unlock the full potential of this emerging copper-gold porphyry system.