Stock image. Gold, silver and platinum jumped to all-time highs on Friday to extend a historic end-of-year rally for precious metals, with support from escalating geopolitical tensions and US dollar weakness.Spot gold set a new all-time high of $4,540 an ounce and the most active US gold futures for delivery in February traded as high as$4,584 an ounce, before pairing gains to $4,555 an ounce in afternoon trade.March silver futures surged by more than 9$78.30 in New York, trading near the day’s highs ...