Green River Lithium Assays Jump 44% to 135 mg/l, Anson Reports

Significant Grade Upgrade at Green River

Anson Resources Ltd (ASX, ASN) has announced a substantial uplift in lithium grades at its Green River Lithium Project in Utah, USA. Recent swabbing of the Bosydaba#1 well returned lithium concentrations averaging 135 mg/l, marking a 44% increase over the 93.5 mg/l grade used in the company’s maiden JORC resource estimate. This boost is attributed to the natural 'cleaning' of the aquifers during brine extraction, which has opened up higher-grade porous layers within the Mississippian Leadville Limestone formation.

Understanding the Aquifer Dynamics

The swabbing process, involving the extraction of approximately 600 barrels of brine daily over several days, revealed that lithium values increased over time. Initially, drilling muds had clogged the formation's voids, but sustained brine flow effectively 'cleaned' these pathways, allowing richer lithium brine to flow. This phenomenon not only confirms the presence of a massive lithium-rich brine aquifer but also highlights the dynamic nature of the reservoir, which could enhance future extraction efficiency.

Clean Brine Enhances Extraction Economics

Importantly, the Green River brine is characterized by low concentrations of salts and contaminants such as iron and boron, which are typically challenging to manage in lithium extraction. Compared to other US lithium brine projects like Standard Lithium’s Southwest Arkansas and the Salton Sea, Anson’s brine offers a cleaner feedstock. This purity is expected to reduce operational costs (OPEX) by lowering the volume of brine needed and minimizing disposal requirements, while maintaining a high lithium recovery rate of 98% through Direct Lithium Extraction (DLE) technology.

Future Resource Expansion and Exploration Plans

Building on these promising results, Anson plans to incorporate the higher lithium grades into an upcoming JORC Mineral Resource upgrade. The company is also preparing to re-enter and deepen the Mt Fuel-Skyline Geyser well, targeting an extension of the Leadville Limestone aquifer thickness beyond 550 feet. This deeper drilling aims to unlock additional reservoir potential and provide further insights into the hydrological properties of the brine aquifers. Monitoring aquifer characteristics and drawdown will be critical to refining resource estimates and optimizing extraction strategies.

Strategic Implications for Anson and the Lithium Market

These developments position Anson Resources to strengthen its foothold in the competitive lithium sector, particularly as demand for lithium intensifies amid the global transition to electric vehicles and renewable energy storage. The combination of higher lithium grades and cleaner brine could translate into improved project economics and a more attractive production profile. However, the timing and scale of the resource upgrade, as well as the outcomes of forthcoming drilling and hydrological tests, remain key variables to watch.