Mining vast untapped reserves of bauxite, phosphate, gold, copper and uranium is key to the Saudi Arabia's efforts to diversify its economy away from hydrocarbons.
Over its almost 18-year mine life, Santo Domingo is expected to produce an average of 134-million pounds a year of copper, 4.2-million tonnes a year of iron concentrates and 17,000 annual ounces of gold.
It was supposed to be a year of mine disruptions, with the market anticipating that multiple labour contract expiries would result in at least one strike.