What is the relationship between gold mine and Gold in the context of the input sentence. Choose an answer from: 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.

Barrick Gold this year sold its Cowal gold mine to Evolution Mining , while Rio Tinto, Peabody Energy, Vale and Anglo American are looking to sell or exit their coal portfolios in Australia.

Answer: product_or_material_produced