Used to introduce alumina into glazes, alumina hydrate promotes opacity and a matte finish and increases hardness and durability.†
It can also be used in kiln wash or to protect kiln furniture in salt firings.
Calcined alumina is generally used in the manufacture of high-grade ceramic shapes, refractories and fused alumina abrasives. It can be compressed to produce a fired density of 3.8 or more. Amazingly, ceramic bodies containing 95% or more alumina are being employed to produce ceramic parts for a wide range industries (fired to 1400C or more). Fabrication methods and glazing vary according to application.