Treasure Trove?

Now here's an interesting thing -- I got a message from a lady who enclosed two photos with her email.  This rather interesting object has been revealed on a certain beach, in a secret location, as a result of the recent storms.

Has anybody seen anything similar before?  The romantic side of me thinks it might be a chest full of gold bullion, lost when the Spanish Armada was blown around the west coasts of Britain, with many of the vessels getting shipwrecked.........  It certainly doesn't look like something made by our sturdy Mesolithic ancestors, and lost in the submerged forest.