So much gold, yet in the history of man we have only mined around 9300 m3 of gold. About the size of big Ben.
Just because things are in the mantle or even the crust. Doesn't mean we will ever get access to it, and if we did its would be so costly then yes gold would be a good thing to own.
[/quote]
A cube 21m x21m x 21m is the most common description (blame Wikipedia)
The same article states that most of the gold in the planet is within the core (and therefore unobtainable at current tech levels) , that which is mined currently is widely to be considered the result of meteorite impacts.