In the same interview

WB presented another arguement against gold, which to me is much more convincing one, if validated: All the gold reserve around the world can be piled into a 20mX20mX20m cube. For that cube of gold, is currently valued at 7 - 8 trillion USD, which is more than all the farming land in US, plus 10 XOMs, and more.

I found that number is in conflict with other numbers. Would love to see if any one can shed more lights on them.