A global glut in iron ore is set to continue for perhaps another four years despite a slump in prices as China continues to buy for US$11 more per metric ton than the bare minimum of US$56 needed to avoid losses, Bloomberg reported, citing data from Goldman Sachs Group (GS.NYSE) and its own intelligence service. The glut emerged this year after a record expansion of mine capacity and as China grew at the slowest pace in two decades. The surplus will reach 300 million tons by 2017 since Chinese steel production is unlikely to expand fast enough to absorb the excess supply.