Knowing what we know today and how fast exploration technology is advancing, this seems to be less plausible....

The ocean floor haven't been explored yet and chances is packed with gold and other precious metals is... Let's say, quite high not to say 100% certain

Add to that the fact that in a non distant future we will be able to mine the asteroid belt for gold and other minerals and there you have it, not a scarce precious mineral any more and therefore not an appealing hedge or money...