Greens MP Adam Bandt says the Government's excuse for excluding gold from the mining tax does not wash.
Mr Bandt asked the Treasurer about putting gold in the mining tax in Question Time today.
"Gold is traded on international and local markets. To suggest it can't be taxed because it is mined with other minerals is simply not right", Mr Bandt said.
"Mr Swan's explanation does not wash. His own department recommended gold be in the original mining tax."