Dropping from a 29-month high, gold prices plunged Rs. 360, to Rs. 30,980 per ten grams at Delhi's bullion market on Monday, on poor demand from jewellers, and a weak trend overseas. But silver rose Rs. 320 , to Rs. 47,400 per kilo, on increased offtake by industrial units and coin makers. Silver coins held steady, at 76,000 rupees for buying 100 pieces.Overseas, gold fell 0.2 per cent, to 1,348 dollars an ounce. Global gold has rallied 27 per cent this year.