Gold prices advanced on Tuesday, remaining comfortably above the key $4,000-an-ounce threshold as markets evaluated renewed diplomatic efforts between the United States and Iran and their potential impact on energy prices, inflation and Federal Reserve policy. Spot gold climbed 1% to $4,049.47 an ounce, while gold futures also rose 1% to $4,054.35. Silver gained 2.6% to $57.87 an ounce and platinum added nearly 1% to $1,611.09. Investors are now looking ahead to next week's Federal Reserve meeting, where policymakers are widely expected to leave interest rates unchanged, with markets currently assigning a 64% probability to a September interest rate increase. Afdhal Rahman, Executive Director of Wealth Advisory at OCBC, noted that renewed tensions in the Gulf could keep oil prices, inflation expectations and the U.S. dollar volatile in the near term, leaving gold under pressure until expectations for tighter monetary policy begin to ease, although sustained central bank buying should continue to provide longer-term support.