CHENNAI (Reuters) - Indian shares made modest gains in a special “muhurat” one-hour trading session for Diwali on Saturday, driven mainly by oil and gas and some banking stocks “Muhurat” means auspicious in Hindi, and many traders believe gains made during this session bring prosperity and wealth in the year ahead. Regular trading resumes on Tuesday. The benchmark BSE index rose 0.45% to 43,637.98, while the NSE index climbed 0.47% to 12,780.25. The S&P BSE oil and gas index settled 1.47% higher. State-run refiner Bharat Petroleum Corp Ltd was the top gainer on the National Stock Exchange, rising 4.8%. Shares in the Tata Steel settled 1.16% higher. Tata Steel said on Friday it had received an approach from Sweden’s SSAB AB about buying its Dutch unit.