Under the proposed mining law amendments, Bougainville would take a 60% share in all projects and retain all mining licences, leaving a 40% share that investors can bid for.
Maricunga is less than 5% the size of the lithium-rich Salar de Atacama in northern Chile, but high-grade deposits of the battery metal makes it attractive to miners.
Pedra Branca underground mine is expected to have an annual production of about 18,000 tonnes of copper and 11,000 ounces of gold over an eight-year mine life.