Here's a breakdown:

* Bauxite: This is the primary ore of aluminum. It is a sedimentary rock consisting mainly of hydrated aluminum oxides, such as gibbsite, boehmite, and diaspore.

* Corundum: This is a mineral composed of aluminum oxide (Al₂O₃). It's a very hard mineral, second only to diamond on the Mohs hardness scale.

In simpler terms: Both bauxite and corundum are rich in aluminum, but they are different forms of aluminum oxide.