World's largest gold coin could fetch $4 million at auction

The $1 million dollar face value Canadian Maple Leaf gold coin is to be auctioned off in Austria at the end of this month.

The record-breaking world's largest coin had been on loan to a museum in Vienna when its owner, an Austrian investment firm went bankrupt.

Michael Beckers, an auction expert, told the BBC how new methods had to be used to mint the coin . . .

Watch video at: BBC News