Australian Mineral Exploration Review 2025 Maiden Mineral Resources

A maiden Mineral Resource is the first report of a Mineral Resource estimate for a new deposit or a new commodity at an existing deposit. They have not had any prior Mineral Resources or Ore Reserves defined under a reporting code recognised by the Committee for Mineral Reserves International Reporting Standards²⁵ such as the JORC Code²⁶. Maiden resources are usually reported in public announcements to stock exchanges such as the ASX and represent an important milestone for exploration projects as they provide an initial indication of the scale, grade and potential economic significance of a discovery. An expanded definition for maiden Mineral Resources can be found in Appendix E.

The discovery and definition of new mineral resources is fundamental to building Australia’s resource wealth and supporting a diverse mining sector. In 2025, 50 projects across Australia reported maiden Mineral Resources, comprising 69 individual maiden resource announcements at the deposit level (Table 1; Figure 4). Of these, 32 included a critical mineral,19 contained a strategic material, and 14 contained both critical minerals and strategic materials. Gold, a precious metal, was the most frequently reported commodity, occurring in 34 maiden resources, followed by copper in 13. Among critical minerals, tungsten and REE were the most frequently reported, occurring in 8 and 7 maiden Mineral Resources respectively, followed by gallium in 5 and titanium in 4 (Table 1).

Collectively, the 2025 maiden Mineral Resources made notable additions to Australia’s minerals inventory²⁷, particularly for critical minerals that have relatively small existing resource bases. The largest proportional impacts were recorded for indium and gallium. Maiden Mineral Resources increased the Australia’s Economic Demonstrated Resource (EDR) of indium by over 300% and Inferred Mineral Resources by 13,000% and increased Inferred Mineral Resources of gallium by 413% (Table 2). Other substantial additions to Australia’s EDR included: antimony, with maiden Mineral Resources equivalent to 17% of the 2024 national EDR and 73% of Inferred Resources; bismuth, equivalent to 20% of EDR and 8% of Inferred Resources; cobalt, equivalent to 4% EDR and 15% of Inferred Resources; and nickel, equivalent to 6% of EDR and 21% of Inferred Resources. Maiden Mineral Resources also made meaningful increases to national Inferred Resources for high-purity silica (38%), niobium (21%) and tungsten (14%) (Table 2). Compared to 2024, the 2025 results indicate a modest rebound in project-level activity, with 50 projects reporting a maiden Mineral Resource compared to 45 in 2024, although still below the recent peak of 77 projects in 2023. This could reflect the decline in new deposit drilling since 2021 (Figure 2b), as exploration expenditure has shifted towards existing deposits and gold-focussed projects.

Despite this, Australia’s 2025 maiden Mineral Resources demonstrate the continued diversity and depth of the national minerals pipeline. Importantly, they include numerous significant critical mineral deposits that are essential to Australia’s future resource security, clean energy and advanced manufacturing capability. The scale of additional resource for commodities such as REE, gallium, titanium, nickel, tungsten, niobium, antimony and high-purity silica highlight the ongoing role of mineral resource discoveries in expanding Australia’s critical minerals endowment and supporting long-term economic and strategic priorities.

The size classifications for maiden Mineral Resources have been calculated using the method developed by Cassard et al. (2015) and applied to the primary commodity of the deposit²⁸.