It’s been a rocky road (pun intended) for Rio Tinto investors since the company’s July 16 quarterly update which, as you may recall, was an absolute stinker. The mining giant has contrived for itself dual maelstroms: material time and cost overruns bringing the Oyu Tolgoi copper mine (the pet project of chief executive Jean-Sebastien Jacques) online in Mongolia and sudden production problems – hitting grade, volumes and unit costs – at its iron ore (AKA bread and butter) division in Western Australia.