New Delhi: Gold extended gains for the third straight day by adding 40 to 29,220 per 10 grams today, on sustained buying by stockists for the ongoing marriage season amid firming global trend. However, silver lacked necessary follow up support at existing higher levels and declined by 150 to 55,750 per kg. Gold remained in demand among jewellers and stockists to meet the ongoing heavy marriage season demand and maintained the uptrend in the third straight session. Buying activity also picked up as gold rose the most in two weeks in global markets as a weaker dollar accelerated demand for the yellow metal as an alternative investment. Gold in global markets, which normally sets the price trend on the domestic front, shot up by $29.60 to $1,709.90 an ounce in New York last night. On the domestic front, gold of 99.9 and 99.5 percent purity added another 40 each to 29,220 and 29,080 per 10 grams, respectively. The metal had gained Rs 290 in last two trading sessions. Sovereigns remained flat at 23,300 per piece of eight grams. On the other hand, silver ready fell by 150 to 55,750 per kg, while weekly-based delivery inched up by 45 to 55,045 per kg on speculative support. Silver coins continued to be asked around previous level of 62,000 for buying and 63,000 for selling of 100 pieces.