Mumbai: The Bombay Stock Exchange benchmark Sensex on Thursday recovered from a nine-week low and surged 197 points on emergence of buying, spurred by higher profit earnings posted by blue chips amid a firming global trend. The 30-share index shot up by 197.40 points to 18,044.64, on the back of a rally in blue chip stocks Reliance Industries (RIL), Coal India and Tata Steel. It had sunk to its lowest since March 21 after it lost 165 points in the previous session. Broad-based National Stock Exchange index, Nifty, climbed 63.40 points to 5,412.35, after the recovery in metal, realty, banks and refinery stocks. Trading sentiment turned bullish on reports of attractive quarter earnings posted by Tata Steel, PSU miner Coal India Ltd and private energy major Cairn India. Tata Steel jumped 1.98 per cent to Rs 572.60, Coal India by 3.22 per cent to Rs 389.15, and Cairn India gained 1.40 per cent to Rs 342.85, buoyed by solid numbers for the quarter ended March 31. Smooth carry forward of positions for next month contract in the derivatives segment and a firming trend overseas helped balance fears of further rise in interest rates on account of high food inflation. Food inflation jumped to 8.55 per cent for the week ended May 14 from 7.47 per cent in the previous week. RIL, the most valuable scrip on the Sensex, rose by 2,92 per cent to six-week high of Rs 933.25 on reports that the government might allow the company to charge market prices for natural gas sold to users other than fertiliser, power companies and for domestic consumption.