Mitsubishi is shelling out nearly $600 million as a joint venture partner for an expanded copper mine project in Arizona.

U.S. President Donald Trump has slammed an appeals court decision to temporarily block plans to develop a massive Arizona copper project. His comments come shortly after he met the chief executives of ...

Copper mining firm Rio Tinto is partnering with Amazon to provide copper from a southern Arizona mine for the tech giant’s next wave of U.S. data centers.

Trump called those opposing the mine ‘Anti-American’ and said the country needs copper ‘NOW!’ Opponents of the mine, including the San Carlos Apache Tribe, said they will never stop fighting to ...

The federal government ceded control to Arizona of "injection wells," a technology important in water management, mining and carbon capture. State environmental authorities will now take charge of the ...