LONDON ( TheStreet) - Rio Tinto ( RTP), the Anglo-Australian mining giant, has bought 15 million shares of Canada's Ivanhoe Mines ( IVN), increasing its stake by 2.7% to 22.4%. The shares were bought for $244.7 million (Canadian), or $232.4 million. "Our further investment in Ivanhoe Mines underlines our confidence in the quality of the world class Oyu Tolgoi deposit and its priority in our project portfolio," said Andrew Harding, Rio Tinto's CEO for copper, in a statement. Oyu Tolgoi is copper-gold project in Mongolia. Rio Tinto said production is expected to begin in 2013, with a five-year ramp up to full expected production of 450,000 tons of copper a year and 330,000 ounces of gold. Rio Tinto said it will own 98.6 million shares of Ivanhoe after the deal is completed. -- Reported by Joseph Woelfel in New York. Follow TheStreet.com on Twitter and become a fan on Facebook.