Gold, as a monetary metal will go away.
Not sure how fast because timing relies on a few inventions.

One invention will be to vibrate gold out of the ground.
Basically, gold becomes almost as plentiful as sand in a desert.
Just go get yer shovel.

The other invention is based on creating true money.
Imagine the difference between bitcoin and the dollar.
Now, there is a step, just as wide, from bitcoin to what i can best describe as true-money (unfortunately, there is a step beyond that...)

Now, while gold is still a monetary metal, its price is WAY!!!! to low.
So, at some point the manipulation ends, and gold skyrockets.

Be sure to trade it for real stuff when it does skyrocket.