Rio Tinto (ASX, LSE: RIO) is looking to sell its boron assets in California as part of the group’s ongoing efforts to simplify its operating model, according to Bloomberg.On Wednesday, the media outlet reported that the Australian mining major will sell all its US boron assets, which include a mine and processing operations in the Mojave Desert town named after the element. Also being sold are Rio’s refinery and shipping facility in Los Angeles port and its Owens Lake mining operation near Sierra Nevada.Tog ...