Premise: HMS "Sussex" was an 80-gun third-rate ship of the line of the English Royal Navy, lost in a severe storm on 1 March 1694 off Gibraltar. On board were possibly 10 tons of gold coins. This could now be worth more than $500 million, including the bullion and antiquity values, making it one of the most valuable wrecks ever.
Hypothesis: HMS "Sussex" left port on 1 March 1693.