Conchas Drilling Yields Up to 0.95% Li2O and 0.39% Rb2O in 33 Holes

Exploration Success at Conchas

Berkeley Energia Limited has announced compelling results from its 2024 drilling campaign at the Conchas Project, located in western Spain near the Portuguese border. The company completed 33 reverse circulation (RC) drill holes and three diamond core holes, all intersecting shallow, thick zones of lithium and rubidium mineralisation within a muscovitic leucogranite host rock. This consistent mineralisation across all holes marks a significant step forward in Berkeley's critical minerals exploration initiative.

The standout intercepts include intervals such as 14 meters at 0.95% lithium oxide (Li2O) and 0.39% rubidium oxide (Rb2O) from 40 meters depth, and a remarkable 61 meters at 0.50% Li2O and 0.21% Rb2O starting from surface. These grades and thicknesses suggest a robust mineralised system with potential economic significance, especially given the strategic importance of rubidium in advanced technology sectors.

Geological and Mineralogical Insights

The mineralisation is hosted within a muscovitic leucogranite unit, which extends approximately 2 kilometers by 1.2 kilometers and varies in thickness from 7 to over 170 meters. Geological logging confirms the homogeneity of this unit, with a strong positive correlation observed between lithium and rubidium grades, likely linked to the presence of lithium-bearing micas. Additionally, tantalum and niobium correlate positively, associated with columbo-tantalite and cassiterite minerals.

Surface mapping has expanded the known extent of the muscovitic leucogranite beyond historical boundaries, enhancing the project's scale. Notably, the southern zone hosts the highest lithium grades, while the northeast area features thicker mineralisation with elevated rubidium levels, hinting at a potential feeder zone yet to be fully delineated.

Strategic Importance of Rubidium

Rubidium's classification as a critical mineral by the United States and Japan underscores its strategic value. Its unique properties make it indispensable in defence, aerospace, communications, medical imaging, and renewable energy technologies. Applications range from night-vision equipment and fibre-optic telecommunications to atomic clocks essential for GPS and space exploration. Global rubidium production is currently limited, with China dominating supply, highlighting the significance of Berkeley's discovery in diversifying sources.

Next Steps and Market Implications

Berkeley has dispatched samples from the diamond core drilling for preliminary metallurgical test work, aiming to assess the recoverability of lithium, rubidium, and associated elements. This testing will include crushing, grinding, gravity separation, magnetic separation, and flotation, with results expected within the current quarter. Concurrently, 3D geological modelling will refine resource estimates and grade distribution, paving the way for potential resource classification upgrades.

While the Conchas Project remains an exploration asset distinct from Berkeley's flagship Salamanca uranium project, these results position the company well within the critical minerals sector, a market segment attracting increasing investor and strategic interest amid global supply chain concerns.