Bauxite, the primary ore of aluminum, does not have a defined cleavage. Cleavage refers to the tendency of a mineral to break along specific planes of weakness in its crystal structure. However, bauxite is not a single mineral but rather a mixture of various aluminum hydroxide minerals (like gibbsite, boehmite, and diaspore), along with other impurities like iron oxides, silica, and clay minerals.

This lack of a consistent crystal structure means that bauxite doesn't exhibit a characteristic cleavage like other minerals. Instead, it will break in irregular fractures, reflecting the variety of minerals and their intergrowths.

While bauxite doesn't have a cleavage, it does have a conchoidal fracture, meaning it breaks in curved, shell-like shapes.