Gold perched above $1,600 an ounce on Wednesday, retaining most of its gains from the previous session as prices were supported by persistent worries over Spain's surging borrowing costs. Spot gold was little changed at $1,610.71 an ounce by 0639 GMT, after rising 0.8 percent in the previous session. US gold futures contract for August delivery edged down 0.1 percent to $1,611.80.