Gold will average $890 (U.S.) an ounce in the third quarter, up from an earlier forecast of $860, while platinum will be $2,220 an ounce, from $1,950 previously, London-based analysts including Suki Cooper wrote in a report yesterday Platinum will advance through next year while gold will decline, the report said.

"Gold's time in the limelight appears to be drawing to a close," the analysts wrote. "Within the precious metals sector, we believe platinum has the best prospects."

Platinum has led gains in precious metals this year, climbing 30 per cent compared with 5.1 per cent for gold. South Africa accounts for 77 per cent of global platinum supply.