Bauxite: The principal ore of aluminum.
Synthetic bauxite is used as an abrasive and as a fracking proppant. Physical Properties of Bauxite. Bauxite is typically a soft material with a hardness of only 1 to 3 on the Mohs scale. ... In the HallHeroult Process, the alumina is dissolved in a molten bath of cryolite (Na 3 AlF 6). Molten aluminum is removed from the solution by electrolysis.