Customs data shows the world's second largest gold miner Russia exported 58 tonnes to be refined in Switzerland last year, but got less than 3 tonnes back.
Banned from travel since 2012, three SouthGobi workers, a coal firm owned Vancouver's Turquoise Hill, are now going to jail for 5-6 years for tax evasion.
"The investigation primarily focuses on offences in respect to the Environmental Management Act and the federal Fisheries Act, but it's not limited to those acts."