1) Orthorhombic mineral 
Boehmite or böhmite is an aluminium oxide hydroxide (γ-AlO(OH)) mineral, a component of the aluminium ore bauxite. It is dimorphous with diaspore. It crystallizes in the orthorhombic dipyramidal system and is typically massive in habit. It is white with tints of yellow, green, brown or red due to impurities. It has a vitreous to pearly luster, a...
white and relatively soft basic aluminum oxide [AlO(OH)] that is a common mineral in bauxite, in which it forms disseminated grains or pealike ... [1 related articles]
Aluminum hydroxide
a mineral, hydrous aluminum oxide, AlO(OH), a major component of bauxite.