Turquoise Hill Resources Ltd. appointed Jo-Anne Dudley as COO, effective June 3.

Dudley led the company's planning unit for the Oyu Tolgoi copper-gold mine in Mongolia. She also worked as a member of Rio Tinto's technical group on mines in South Africa and the U.S., according to the same-day release.

Over 40% of Turquoise Hill's minority shareholders recently opposed the reelection of four of its seven independent directors due to the board's refusal to discuss certain governance issues.