Sandfire Resources (ASX:SFR) signed a binding term sheet with Havilah Resources (ASX:HAV) to advance the Kalkaroo project in South Australia, according to a Thursday filing with the Australian bourse.

The company may earn an 80% interest in the project through a two-stage earn-in arrangement, comprising AU$105 million upfront consideration and a further AU$105 million upon completion of a new pre-feasibility study, the filing said.

The company will also commit AU$30 million to regional exploration across a minimum 24-month period under the deal, per the filing.

Sandfire Resources shares fell 1% in morning trade on Thursday, while Havilah Resources shares were up nearly 30%, reaching their highest since August 2017.