Ioneer’s Rhyolite Ridge lithium-boron resource in Nevada soars by 168%

The Rhyolite Ridge lithium-boron project in Nevada. (Image courtesy of ioneer.)

A leap in the estimated resources at Ioneer’s (NASDAQ: IONR; ASX: INR) Rhyolite Ridge lithium-boron project in Nevada could give the site enough lithium to charge more than 50 million EVs, as the company eyes first production in 2026.

An updated resource estimate, released on Thursday, puts the South Basin deposit at the project at 360.2 million tonnes at 1,750 parts per million (ppm) lithium and 6,850 ppm boron for about 3.4 million tonnes of lithium carbonate equivalent (LCE) and 14 million tonnes of boric acid equivalent (BAE).

A 2020 feasibility study pegged the resource at Rhyolite at 146.5 million tonnes of LCE and 11.9 tonnes of BAE in a 3 sqkm area.

“We are extremely pleased with the significant increase in the South Basin Mineral Resource estimate,” said ioneer executive chairman James Calaway. “It highlights Rhyolite Ridge’s optionality and multi-generational scale potential to provide a secure, sustainable and reliable domestic source of lithium for the growing electric vehicle battery supply chain.”

About 80% of the resource is classified as measured and indicated. Inferred resources total 65.7 million tonnes for 630,000 tonnes LCE at 3,550 ppm and 1.8 million tonnes BAE at 14,600 ppm.

Cut-off grades of 1,090 parts per million (ppm) lithium and 5,000 ppm boron, remain unchanged.

The increased resource takes into account drilling and assays from all four stratigraphic layers underneath the lake-bed sedimentary rocks of the Cave Spring Formation in Nevada. The 2020 resource analyzed just two layers. All four layers remain open to the north, south and east, with further potential for resource growth.

The Sydney, Australia-headquartered company said it estimates the Rhyolite site now holds enough lithium carbonate to power more than 50 million electric vehicles. It added that once the project is permitted and construction is complete it is expected to quadruple current lithium chemical output in the U.S.

It is currently going through its final phase of permitting and anticipates starting construction of the mine in 2024, with production beginning in 2026.

Rhyolite Ridge is located about 60 km southwest of Tonopah, in southwestern Nevada. It is the only known lithium-boron deposit in North America and one of only two known such deposits in the world.

Ioneer shares traded at A30¢ in Sydney on Thursday, in a 52-week window of A26¢ and A74¢, valuing the company at A$629.5 million.