Who were the Exports of Gold and Silver from the New World to Spain?

If this question means "Who exported gold and silver from the New World to Spain"? Then the answer is the Spanish conquistadors and Spanish explorers.

Vast amounts of these precious metals were also precious to the advanced Native American peoples in Mexico and further south. The Aztecs, Mayans and Incas all valued gold & silver.

What Spain did not steal from these civilizations were later mined, as the New World under Spain's dominion had vast mines of gold and silver.