As in they didn't confiscate all of it? Or, they didn't confiscate it at all?
I do believe that they did grab hold of all of it, paid for it eventually at half price, and then outlawed the owning of gold bullion by the average citizen for quite a while.
See: http://mises.org/story/3056
Outlawing the ownership of gold pretty much means a forced sale to the government, which is close enough to confiscation for me.
They did not confiscate all of it. Many people hid their gold. Those with a lot of gold put it in European banks vaults (and the fortunate chose Switzerland rather than Germany or France as their banking location).