Stocks sparkled on Diwali, as the Sensex at the Bombay Stock Exchange surged 111 points, or 0.5 percent, to cross the crucial 21,000 point mark, and settle at a new all-time closing high of 21,005, in a special 'Muhurat' trading session, between 6 p.m. and 7.15 p.m., today. The Nifty at the National Stock Exchange gained 31 points, or 0.5 percent, to 6,312.Over at Delhi's bullion market, silver spurted 1,300 rupees, to a new all-time peak of 38,900 rupees per kilo, on hectic festive buying. Gold jumped 250 rupees, to 20,100 rupees per ten grams.In the overseas markets, gold rose to a record above 1,394 dollars an ounce.