Ioneer (ASX:INR) closed a $996 million loan from the U.S. Department of Energy's loan programs office to support the development of an on-site processing facility at its Rhyolite Ridge lithium-boron project in Nevada, according to a Monday Australian bourse filing.

The mining firm said the 20-year $996 million loan, with a principal of $968 million and $28 million in capitalized interest, is a $268 million increase in loan principal from the January 2023 conditional loan commitment.

Rhyolite Ridge is fully permitted and construction ready, Bernard Rowe, the firm's managing director added. It received a positive record of decision from the US Department of Interior in October 2024, the filing said.

It plans to close the conditional joint venture with miner Sibanye-Stillwater to fund $490 million for a 50% share of the Rhyolite Ridge project.

Conditions precedent to first loan funding include closing the joint venture, securing necessary additional required funding, and a project finance model bring down.

First production is targeted for 2028.

The firm's shares rallied 14% in recent trade.