Ioneer Ltd (ASX: INR, Nasdaq: IONR) has announced a significant improvement in the project economics for its 100%-owned Rhyolite Ridge Lithium-Boron Project in Nevada, USA. Ioneer is an emerging lithium–boron producer, and the Rhyolite Ridge project contains the largest Lithium-Boron Reserve in the world. The company’s latest optimisation efforts have yielded a substantial increase in the project’s net present value and internal rate of return.
The company achieved these improvements by further reducing the vat leach retention time from two days to 1.5 days. This reduction allows for increased ore processing while maintaining consistent acid usage, resulting in a 9% increase in annual lithium hydroxide production to 27,800 tonnes per annum (tpa) and a 7% increase in annual boric acid production to 135,500 tpa. The company also stated that the all-in sustaining cash cost is US$4,628 per metric tonne of lithium carbonate equivalent.
The enhanced production profile has led to a 19% increase in the unlevered life of mine NPV to US$2,237 million and an 8% increase in the unlevered life of mine IRR to 18.0%. According to Ioneer, Rhyolite Ridge is the only known lithium deposit globally amenable to vat and heap leaching, facilitating on-site production of high-purity lithium and boron chemicals. The company believes the project’s ore reserve and mineral resources support future expansions to meet growing US demand for both lithium and boron.
‘By cutting our leach processing time in half, Ioneer will now deliver more critical minerals faster to our partners as we collectively work to strengthen American critical mineral supply chains,’ said Bernard Rowe, Managing Director of Ioneer. According to the release, these improvements were made with minimal increases in project capital costs and no changes to the processing plant design. Ioneer continues to advance Rhyolite Ridge toward a Final Investment Decision.
