Copper Cliff North MineCopper Cliff North Mine is an underground nickel mine in Copper [Cliff, Ontario|Copper Cliff], Ontario, Canada. It is owned and operated by Vale Canada Limited.HistoryThe mine was the 2007 winner of the John T. Ryan Trophy for metal mines. Employing approximately 260 people, the mine went through 2006 without a lost-time-accident, producing of 4,200 tonnes of ore per day.