Studies on Extraction of Potassium from Feldspar by Roast .
Page 66 in this online book talks about a plant in the Ukraine that smelts kaolin into an aluminum/silicon alloy: The Handbook of Aluminum by George E Totten, D Scott MacKenzie. (are you sure, it is well know that soviet used kaoline/clays + lime smelt to produce alumina, feeded to normal Hall cells.The common feldspar mining processes include hand sorting, desliming, magnetic separation, gravity separation, flotation and combined process, which can separate quartz, iron, mica and other minerals. 1. Pegmatite feldspar mining process. Commonly, the pegmatite feldspar has good quality feldspar ores, which has simple mineral constitute.