Two decades ago, Anglo American created the world’s No. 1 gold miner by merging its South African assets. Having long since been eclipsed by its rivals, AngloGold Ashanti may need to leave home to keep up. Newmont Mining and Barrick Gold have forged megadeals that will extend their lead over AngloGold. Saddled with Mponeng, the world’s deepest mine in a dying South African industry that’s struggling to contain costs, the third-biggest producer could boost its value by leaving the country, according to Rene Hochreiter, analyst at Noah Capital Markets in Johannesburg.