Ioneer Ltd (ASX:INR, OTC:GSCCF, NASDAQ:IONR) is highly encouraged by its latest leach tests that indicate the Rhyolite Ridge Project has the potential to boost the US domestic supply of lithium, a crucial element for electric vehicle batteries.
This development comes at a time when US domestic demand for lithium is on the rise, bolstered by a 15% increase in the 2035 demand forecast, following the passage of the Inflation Reduction Act.
Positive leach tests
Latest leach tests indicate that up to 79% of the project’s 360 million tonnes mineral resource can be effectively processed.
This positions Ioneer to quadruple US lithium production by 2026 and to substantially increase supply over time as well as to help rebalance the global production of boric acid.
The tests reaffirm previous estimates that the Rhyolite Ridge site contains enough lithium to power more than 50 million electric vehicles.
Tests targeted low-boron (Type 3) mineralisation, a material previously excluded from the project's economic analyses but within the mine footprint.
Results reveal leach recoveries between 89% and 94% coupled with free-draining characteristics, exceeding expectations and confirming the potential for heap or vat leaching methods similar to those to be used for processing the already-included Type 1 mineralisation.
Three distinct styles of lithium mineralisation, recognised in the April 2023 mineral resource estimate, consist of:
- Type 1 mineralisation - lithium with high boron and low clay content (searlesite dominant, mainly illite clay) 152 million tonnes mineral resource containing 1.2 million tonnes of lithium carbonate equivalent (LCE).
- Type 2 mineralisation - lithium with high clay content (dominantly smectite clay) 75 million tonnes mineral resource containing 1 million tonnes of LCE.
- Type 3 mineralisation - lithium with low boron and low clay content (feldspar dominant, mainly illite clay) 128 million tonnes mineral resource containing 1.1 million tonnes of LCE.
“Rhyolite Ridge is one of a limited number of lithium projects in the US expected to begin production this decade,” said managing director Bernard Rowe.
“These results further reinforce Rhyolite Ridge’s unique mineralogy and our ability to deliver these urgently needed battery materials within the existing footprint of our proposed mine site.
“We look forward to completing the important federal permitting process, delivering these critical and valuable materials and strengthening domestic EV supply chains.”
The project is anticipated to commence construction in 2024 and will significantly contribute to rebalancing global production of boric acid.
Ioneer has secured funding for Stage 1 of construction with commitments of US$490 million in equity from Sibanye-Stillwater and US$700 million in debt from the U.S. Department of Energy’s Loan Programs Office.
Lithium production is expected to follow in 2026.