Mullite-Forming Chamotte Grogs from Germany
Chamotte grogs engineered to form mullite crystals upon firing are calcined clays used in advanced refractories for petrochemical heaters. These grogs are chamotte earths in an unfinished raw state, within the scope of Chapter 25 as they have not been processed beyond crushing, grinding, or calcination.
Duty Rate — Germany → Canada
0%
Import Tips
• Ensure the grogs are not pre-fired to the mullite stage, as mullite itself is classified under a separate heading (2508.60.00)
• Provide technical data showing the grogs are designed to form mullite only upon further firing by the end user
• Verify the product has not been mixed with other oxides or additives