By Barani Krishnan Investing.com -- Gold perked for a third straight day on Thursday as the dollar wilted on the eve of the Federal Reserve's annual gathering in Jackson Hole, Wyoming, where central bank chief Jerome Powell was expected to deliver a pivotal speech on rate hike expectations. The benchmark gold futures contract on New York's Comex, December, settled at $1,771.40 per ounce, up $9.90, or 0.6%. In two prior sessions, December gold rose almost 0.9%. The spot price of bullion, more closely followed than futures by some traders, was at $1,757.63 by 16:12 ET (20:12 GMT), up 0.4% on the day. Like futures, spot gold was also up some 0.9% over two previous sessions. "Gold got a limited boost as the dollar softened ahead of Fed Chair Powell's speech at Jackson Hole," Ed Moya, analyst at online trading platform OANDA, said in a commentary. "Another round of US economic data and Fed speak supported the idea that the Fed will remain aggressive tightening pol...