Calcined Bauxite

close box The applications which
can use this mineral are
highlighted. Please select
one to learn more.
Product Benefits
Technical Details

Calcined bauxite (aluminium oxide) is produced from Refractory Agglomerated Super Calcined (RASC) bauxite. The main constituent is the mineral corundum. Calcined bauxite can be characterised by:


  • High Mohs hardness of 8.5
  • High inertness in various media.


Basic properties

Property Value Unit
Moisture 0.1 [%]
Hardness (Mohs) 8.5 [-]
Colour dark grey [-]
Density 3.8 [kg/ dm3]





Product overview

Product Grade D50





[g/ 100 g]

Portalum A25 10 41 13

Production location Portalum

Portalum B is the brand name of Sibelco’s calcined bauxite grade for coatings applications.



  • Excellent abrasion resistance: due to its hardness of 8.5 on Mohs scale, calcined bauxite will increase the coating’s resistance to wear.
  • Chemical resistance: due to its inert nature, calcined bauxite provides good chemical resistance compared to conventional fillers.

Sibelco © 2024