Gold traded little changed on Thursday, unable to break above a key resistance at $1,585 an ounce, as investors wait for major central banks' decisions on monetary policy and a firmer dollar weighed on sentiment. Spot gold was little changed at $1,584.31 an ounce by 0640 GMT. US gold gained 0.6 percent to $1,583.90. The popular gold forward contract on the Shanghai Gold Exchange dropped to a two-week low of 317.5 yuan a gram, or $1,587 an ounce, before paring losses to 319.1 yuan.