Mammoth Minerals Advances High-Grade Drilling and Maiden Resource at Excelsior Springs

Bonanza Grades Ignite Maiden Drilling at Blue Dick

Mammoth Minerals (ASX:M79) has launched its first-ever reverse circulation (RC) drilling program at the Blue Dick Mine prospect in Nevada, following a series of extraordinary surface assay results that include silver grades topping 17,000 grams per tonne (g/t). The company’s recent channel and rock chip sampling campaigns revealed polymetallic bonanza zones, with highlights such as 0.20m at 17,582g/t silver, 0.75g/t gold, and 2.76% copper, and rock chips returning up to 15,336g/t silver alongside 7.46g/t gold.

This drilling initiative aims to test over 6.5 kilometres of prospective strike, unlocking further extensions of these high-grade zones. The Blue Dick Mine, originally discovered in the 1870s, has never before undergone modern drilling, positioning Mammoth to potentially rewrite the understanding of this historic site’s mineral potential.

Buster Mine Maiden Resource on the Horizon

Meanwhile, Mammoth is progressing towards a maiden Mineral Resource Estimate (MRE) for the Buster Mine zone, with the database now closed out and validation complete. The Buster Trend, encompassing over 7 kilometres of geophysical anomalies, has already seen extensive drilling, including 18 kilometres of RC and 3 kilometres of diamond drilling. Historic intercepts include substantial gold grades such as 51.8m at 4.00g/t gold and 33.5m at 5.35g/t gold, underscoring the scale of this Carlin-style mineral system.

The upcoming MRE, expected in the September quarter, will be a critical milestone for Mammoth, potentially converting exploration success into a defined resource that could underpin future development decisions.

Expanding Drill Targets across Excelsior Springs

Beyond Blue Dick and Buster, Mammoth’s exploration at the Excelsior Springs project is rapidly expanding. The Imperial Gold Mine, a former high-grade producer, continues to reveal shallow, open-ended gold mineralisation with significant copper results from recent sampling, including channel samples grading up to 9.35% copper. The nearby Railroad Springs prospect has also delivered impressive silver assays exceeding 1,600g/t, elevating it to drill-ready status for later in the RC campaign.

These developments contribute to a growing pipeline of high-quality drill targets across the Excelsior Springs mineral claims, supported by ongoing mapping and sampling programs that enhance geological understanding and targeting precision.

Broader Portfolio and Corporate Updates

Outside Nevada, Mammoth is advancing exploration and corporate initiatives across its portfolio. The Bella Gold Project in South Dakota is undergoing data integration and targeting, while the Skyline Copper Project in Newfoundland is being evaluated for commercial opportunities amid strong copper markets. In Peru, the Picha Copper-Silver Project continues structural and geochemical mapping, with drill permitting progressing for the Ichucollo target. The Charaque Gold-Silver Project has attracted third-party interest, with potential corporate transactions underway to streamline Mammoth’s asset base.

On the corporate front, Mammoth ended the quarter with $2.0 million in cash and no debt, having spent $1.73 million on exploration. The company also holds a 19.9% stake in Cloudbreak Discovery PLC following the divestment of its Paterson Copper-Gold Project.

Strategic Focus on Precious and Critical Minerals

Managing Director Glenn Poole emphasised the strategic value of Mammoth’s exploration pipeline, highlighting the polymetallic nature of the Excelsior Springs system, which hosts precious metals alongside critical minerals such as copper, antimony, lead, and zinc. The company’s September quarter priorities include delivering the maiden MRE for Buster and advancing RC drilling across Blue Dick, Imperial, and Railroad Springs, aiming to unlock the full potential of this emerging district-scale mineral system.

With maiden drilling underway and resource definition imminent, Mammoth Minerals is positioning itself at the forefront of high-grade mineral exploration in one of the world’s premier mining jurisdictions.