Jan 13 Canada's Sherritt International Corp and Japan's Sumitomo Corp said on Wednesday they would book more than $1.7 billion of losses on their Ambatovy nickel mine in Madagascar, as prices at 12-year lows wreak havoc among miners. The companies had been ramping up production at the 60,000 tonne a year nickel mine, but the prolonged slump in commodities is taking an ever greater toll on miners and traders, forcing losses, asset sales and writedowns, with no end in sight as the new year starts.