Utilize the input text as a context reference, choose the right relationship between Antofagasta Plc and ANTOFAGASTA from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

* ANTOFAGASTA : Barrick Gold Corp agreed on Thursday to sell 50 percent of its Zaldivar copper mine in Chile to copper miner Antofagasta Plc for $1 billion in cash, and both parties stressed that this was just the start of more cooperation.

Answer: location_of_formation