By Ali Lyon One of Anglo America’s top investors has called for the London-listed miner to mothball its flagship fertiliser mine in North Yorkshire because it won’t provide a good enough return on investment. The mine, which when complete will tap into the world’s largest known deposit of a yield-boosting chemical called polyhalite, employs an estimated 2,000 people in Yorkshire, some of which are believed to be at risk as a result of the slowdown. But Dawid Heyl, a portfolio manager at Ninety One, which owns roughly 1.5 per cent of Anglo’s shares worth roughly £500m, has said that the Woodsmi…