American Uranium (ASX:AMU) advances Lo Herma with fresh drilling success

American Uranium has reported encouraging early results from its 2026 drilling campaign at the Lo Herma ISR Uranium Project in Wyoming’s Powder River Basin, with five resource expansion holes completed and further drilling underway ahead of an updated Mineral Resource Estimate expected by the end of Q1.

The programme is focused on extending mineralised trends north of the proposed Mine Unit 2, reinforcing the project’s development trajectory within one of the United States’ most established in situ recovery uranium districts.

Highlights

• 5 resource expansion holes completed in 2026 for ~2,249m
• Best total hole GT of 0.6 over 5.8m, including 1.8m at 0.042% eU3O8 in LH-26-002
• Approximately 10 additional holes to be completed within 2 weeks ahead of an interim MRE update by end of Q1
• Drilling targeting projected redox trends north of Mine Unit 2, with current projections extending over 1,200m

The 15 hole programme, of which one third has now been completed, is designed to build on the 50 hole campaign reported in December 2025 and to expand the resource base along projected roll front trends.

The best result from the current batch returned a total mineralised thickness of 5.8m above a 0.02% eU3O8 cutoff, with a higher grade intercept of 1.8m at 0.042% eU3O8 in hole LH-26-002.

The remaining holes confirmed continuity of host sand units and redox conditions, with smaller intercepts interpreted as oxidised tails within the roll front system.

Lo Herma hosts an Indicated and Inferred Mineral Resource of 6.21Mt at 630ppm U3O8 for 8.57Mlb contained U3O8, including 2.78Mt in the Indicated category.

An Exploration Target of 5.59Mt to 7.10Mt at 500ppm to 700ppm U3O8 has also been defined.

The present drilling is intended to support an updated MRE and subsequent scoping study work, with further infill and expansion drilling, as well as installation of additional monitoring wells, planned through CY2026.

The geological context underpins the strategy. Mineralisation at Lo Herma occurs as sandstone hosted roll front deposits within the Eocene Wasatch and underlying Paleocene Fort Union formations of the Powder River Basin.

The basin has been the backbone of Wyoming U3O8 production since the 1970s and is home to multiple permitted ISR processing facilities in proximity to the project.

Drilling is targeting extensions of previously interpreted mineralised trends at depths of approximately 450m, with current projections indicating a trend length exceeding 1,200m and remaining open to the north.

Chief executive Bruce Lane said the company was pleased with the early outcomes.

“We are delighted that this resource expansion drilling has continued to deliver strong results, and we believe that these results, combined with our 2025 campaign at Lo Herma, can be brought into additional resource pounds when we update the resource at the end of March. AMU continues to both grow and de-risk the Project as we progress toward an update of the Lo Herma MRE at the end of the quarter.”

Beyond the immediate programme, the broader permit allows for up to 121 drill holes and 37,500m, positioning the company to resume drilling quickly in Q2.

With 1,007 drill holes now within the project area and extensive historical data underpinning the resource base, the upcoming MRE update will provide the next measurable step in assessing scale and confidence.

In a basin with established ISR infrastructure and a long production history, incremental resource growth and category upgrades remain central to Lo Herma’s progression toward potential ISR mine development.

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