MUMBAI: Standard gold zoomed by Rs. 65 to Rs. 8,770 (10 grams) and silver (.999 fineness) by Rs. 790 to Rs. 19,335 a kg, respectively, on the bullion market here on Tuesday owing to firm global advices. According to market participants, operators were busy in building up long positions ahead of a possible launch of a silver exchange-traded fund (ETF) that would be traded on the American Stock Exchange.