Gold futures edged down early Wednesday, with the dollar and the international talks on the Mideast conflict in Rome expected to drive trading. Gold for August delivery was last down $2.50 at $615.50 on the New York Mercantile Exchange. Other metals prices were mixed. Silver edged down less than a cent at $10.940 an ounce and palladium dropped $3 at $314 an ounce. Platinum rose $3.50 at $1,233 an ounce. Copper was last down 7.60 cents at $3.385 a pound