On board were at least 100,000 pounds of gold (over US$1.5 billion in today's money),[3] 400 bars of Mexican silver (another 1 million) and nearly 500,000 pieces of eight and other coins, making it one of the most valuable wrecks of all time.

When a Spanish ship in Cadiz at the same time caught fire just before she was due to carry treasure to convert into pay for Spain's 30,000 soldiers in Flanders, the Royal Merchant's Captain Limbrey saw his chance to make a little more cash for his owners.

The Royal Merchant kept leaking after she and her sister-ship left Cadiz and, when the pumps broke down, she sank off Land's End in rough weather on 23 September 1641.

[5] The Odyssey team is still uncertain as to the identity of the wreck, but now believe it may be the Nuestra Señora de las Mercedes, a Spanish vessel sunk in 1804.

In more recent times an anchor was trawled up by fishermen off Land's End and the media wrongly printed that the wreck had been found.