Galileo Mining’s latest diamond drilling at Norseman reveals a newly identified ultramafic sill with 109 metres of PGM mineralisation, reinforcing the project’s potential for multiple stacked intrusive systems along extensive strike lengths.
- 109m @ 0.21 g/t PGM from new ultramafic sill
- Over 20km strike prospective at Callisto, 12km at Mission Sill
- Upcoming 5,000m aircore drilling to target sulphide zones
- Planned metallurgical testing to improve metal recovery confidence
- Callisto hosts unique Platreef-style PGM-nickel-copper resource
Discovery of Extensive PGM Mineralisation in New Ultramafic Sill
Galileo Mining Ltd (ASX:GAL) has unveiled compelling diamond drill results from its Norseman project in Western Australia, highlighting a newly identified ultramafic (pyroxenite) sill that hosts a broad zone of platinum group metals (PGM) enrichment. The standout intercept spans 109 metres grading 0.21 g/t 3E (Pd+Pt+Au), underscoring the potential for stacked intrusive sills across the region.
This discovery is particularly significant as it expands the known mineralised footprint beyond the established Callisto resource, which itself is notable for its Platreef-style PGM-nickel-copper sulphide mineralisation. The new sill’s intrusion into volcano-sedimentary host rocks and evidence of internal layering suggest a complex mafic-ultramafic system with multiple mineralised horizons.
Extensive Strike Lengths at Callisto and Mission Sill Prospects
The company interprets the Callisto and Mission Sill prospects as accumulations of numerous intrusive sills emplaced along deep-seated structures, forming mafic-ultramafic complexes. The Callisto area boasts over 20 kilometres of prospective strike, while Mission Sill offers an additional 12 kilometres, both ripe for further exploration.
Recent geophysical surveys, including gravity and induced polarisation (IP) data, have delineated strong anomalies coincident with these prospective trends. Upcoming drilling programs are designed to infill and extend these targets, particularly focusing on sulphide-rich zones that have shown anomalous PGM values in previous campaigns.
Following an update from the drilling contractor, a 5,000-metre aircore program targeting Mission Sill is scheduled to commence in early June 2026, aiming to build on the encouraging results from shallow sulphide intercepts and geophysical signatures. This initiative is part of a broader strategy to systematically test the extensive strike potential of the Norseman project. This drilling campaign follows the company’s earlier identification of strong gravity and IP anomalies which highlighted sulphide potential at Mission Sill.
Callisto Deposit: A Unique Platreef-Style Resource
The Callisto deposit remains the cornerstone of Galileo’s Norseman project. Discovered in 2022, it represents the first Australian example of Platreef-style mineralisation, analogous to South Africa’s renowned deposits. The maiden JORC Mineral Resource Estimate reported in 2023 stands at 17.5 million tonnes grading 1.04 g/t 4E (Pd, Pt, Au, Rh) with significant nickel (0.20%) and copper (0.16%) credits.
Diamond drilling beneath Callisto has continued to delineate high-grade zones, with recent assays from drill hole 26NRDD525 confirming wide intervals of mineralisation, including 38 metres at 1.57 g/t 3E within the resource and further intercepts in the newly identified sill. These results complement ongoing metallurgical test work aimed at improving metal recoveries, which to date have been promising, supporting the economic extraction potential of the mineralisation style.
Galileo’s approach to metallurgical optimisation builds on previous work that demonstrated conventional crushing, milling, and flotation methods can achieve substantial recoveries for PGMs and base metals. The upcoming test work on fresh drill core samples is expected to refine these processes and potentially enhance project economics.
Exploration Methodology and Historical Context
The recent drilling campaign was partially funded by the Western Australian Exploration Incentive Scheme, reflecting government support for advancing the project’s exploration. The company employs a rigorous sampling and assay protocol consistent with JORC 2012 standards, including diamond core drilling with HQ and NQ diameters, detailed geological logging, and multi-element ICP-OES and Fire Assay analyses.
Historical exploration in the Norseman region has focused on gold and base metals, with nickel-cobalt resources identified in the past. However, Galileo’s discovery of PGM mineralisation and the unique intrusive system at Callisto has shifted the exploration paradigm. The company’s tenements cover 255 km2, including the Callisto, Mission Sill, and Jimberlana prospects, all prospective for PGE, nickel, copper, cobalt, and rhodium mineralisation.
This extensive tenure and the presence of multiple mineralised sills offer a compelling opportunity for resource expansion. The company’s ongoing exploration is supported by detailed geophysical surveys, including aeromagnetic, ground gravity, and IP data, which have been instrumental in defining drill targets.
Funding and Future Catalysts
Galileo maintains a strong cash position of approximately A$8.2 million, underpinning its aggressive exploration programs. This financial strength allows the company to pursue the planned 5,000-metre aircore drilling at Mission Sill and follow-up diamond drilling at Callisto North and South, where anomalous PGM results warrant further investigation.
Investors should keep an eye on assay results from these upcoming drilling campaigns, as well as the outcomes of metallurgical test work, which will be critical in assessing the project’s economic viability. The company’s ability to convert exploration success into a robust resource and ultimately a mineable deposit remains the key question.
These developments build on the company’s earlier initiatives, including the deep diamond drilling program beneath Callisto and the confirmation of shallow PGE mineralisation at Mission Sill, as reported in recent updates. Galileo’s strategic focus on Norseman’s multi-element potential positions it well within the competitive landscape of Australian PGM and base metal explorers, especially given the scarcity of Platreef-style deposits domestically. strong cash balance supports ongoing exploration(3a093eee-9db1-4ce7-b611-accdbdb5470f4) and the company’s methodical drilling approach have laid a solid foundation for future resource growth.
Bottom Line?
Galileo’s latest drill results reinforce Norseman’s potential as a multi-sill PGM system, but the true scale and economic viability hinge on forthcoming assays and metallurgical outcomes.
Questions in the middle?
- Will upcoming drilling confirm continuity and thickness of mineralised sills along strike?
- How will metallurgical test results impact the project’s processing strategy and cost profile?
- What timeline can investors expect for updated resource estimates and feasibility studies?