New Delhi, Nov 5 (PTI) Jewellers expect a 20-30 per cent rise in gold and silver sales in value terms on Dhanteras on Friday, despite a sharp correction in prices from their January. The 999 purity gold price surged by Rs 10,000 in 1 kg ahead of the Dhanteras and Diwali festivals, where demand for precious metals are high. Among cities, silver is most expensive in.