Before going to Kotzebue, Obama went to Dillingham, home to one of the world's largest sockeye salmon fisheries, where residents are fighting the Pebble Mine copper and gold project that has been proposed by Northern Dynasty Minerals Ltd .
In the context of the input sentence, determine the relationship between 'Pebble Mine' and 'gold'.
Options: chief executive officer, founded by, product/material produced, distribution format