Aluminum oxide is a general purpose abrasive material—it is a less expensive material that ceramic or zirconia alumina. Alumimum oxide is often called alumina in various other applications and is used in a wide array of abrasive products due to its characteristic high hardness. It's also used widely in these applications because the more expensive materials, ceramic and zirconia alumina, are often not needed in finer grits than 120 grit due to offering little over alumina oxide due to lower heat and durability requirements. Fundamentally, as the grit start to move higher (finer) than 120 grit, there is no benefit to more expensive materials. This makes aluminum oxide a fantastic material for the majority of grits on soft to medium hardness materials that need to be shaped or ground down.

Keep in mind, that for very rough grinding or stock removal of something like ¼" steel, a 36 grit aluminum oxide belt will likely quickly run down in life due to the high heat generated at that coarse of a grit. In that case, check out our ceramic and zirconia alumina that while cost more per belt will have substantially longer life in high-heat situations that such coarse grits produce—ultimately saving the knife maker money.