NovaGold Resources (TSX: NG) on Wednesday announced plans to buy the 40% stake it doesn't already own in Donlin Gold Holdings, creating a company valued at $4.2 billion.Why it matters: Mining M&A has hit the motherlode this year.There were $26.3 billion in deals in Q2. That's up 68% quarter over quarter, and is the second highest quarterly total since S&P began tracking the metric in 2013.Driving the news: NovaGold is acquiring the stake it does not own in the Alaskan gold miner from Paulson Advisers, creating a new U.S.-domiciled company that plans to be listed on the NYSE.This would create the "largest gold development project in the U.S.," per the announcement.Paulson has a stake in NovaGold Resources that will leave it with a 40% economic interest in the new business that will be dubbed (wait for it) NovaGold Corp.Flashback: Donlin was valued at roughly $2 billion a year ago, when Paulsen and NovaGold took a 50% stake in the business.The big picture: The price of gold had been surging, and is currently 20% above its price from one year ago, despite retreating from its peak.Growing AI infrastructure and energy transition needs have driven up demand for goods like copper, gold, lithium, and rare earth elements.The Trump administration has also aggressively sought to increase gold production. Last week, it moved forward with a plan to auction off sections of water surrounding American Samoa for potential deep-sea mining.Between the lines: Starting a new mine is costly and time-consuming, and some attempts, including the American Samoa plan, have already hit populist backlash. That's only helped M&A.