In futures trade, silver for delivery in December was up by Rs 407, or 1.03 per cent, at Rs 39,880 per kg at the Multi Commodity Exchange, in a business turnover of 54 lots.
Likewise, the white metal for delivery in September spurted Rs 395, or 1.02 per cent, to Rs 39,258 per kg in 492 lots.
Analysts said widening of positions by speculators in step with a firm trend in global markets as the dollar slipped against a basket of major currencies after the release of the minutes from Federal Reserve's July meeting at which policymakers voted unanimously to keep US interest rates unchanged, influenced silver prices at futures trade.