Martin Frobisher

Sir Martin Frobisher (1535 or 1539 – 15 November 1594) was an English seaman who made three voyages to the New World to look for the Northwest Passage. All of them landed in what is now northeastern Canada, around Resolution Island and Frobisher Bay.
On his second voyage, Frobisher found what he thought was gold ore and carried 200 tons of it home on three ships since initial assaying determined it to be worth a profit of £5.10 per ton. Encouraged, Frobisher returned to Canada with an even larger fleet and dug several mines around Frobisher Bay. He carted 1,350 tons of the ore back, but after years of smelting, it was realised that both that batch of ore and the earlier one he had taken had been worthless iron pyrite.
As an English privateer/pirate, he collected riches from French ships. He was later knighted for his service in repelling the Spanish Armada in 1588.