Exploration and development company Detour Gold raised reserve estimates for its Detour Lake gold project by 5 percent after its 2011 drilling exploration.
It said proven and probable gold reserves -- the part that can be economically mined -- were higher at 15.6 million ounces.
The measured and indicated resources at the northern Ontario gold mine were up 13 percent to 23.3 million ounces, the miner said in a statement.
On Dec. 23, the company had received a go-ahead from the Canadian government, paving the way for the development of what will be one of the country's largest gold mines.
The Detour gold mine is expected to employ about 1,200 workers during the construction phase and about 500 once it goes into production.
Shares of the company closed at C$26.60 on Tuesday on the Toronto Stock Exchange.