Gold and silver extended their sell-off Monday, deepening losses from last Friday's rout as a firmer dollar and profit-taking drains momentum from a rally that had propelled the precious metals to record highs just days earlier. Spot gold lost around 5% to $4,617.07 per ounce, having crashed nearly 10% on Friday, when prices plunged below $5,000 an ounce. Silver, which had surged alongside gold on safe haven demand and speculative inflows, also remained under pressure after last Friday's 30%