Mullite-Forming Chamotte Grogs from China
Chamotte grogs engineered to form mullite crystals upon firing, used in advanced refractories for petrochemical heaters. Classified under HTS 2508.70.00.00 as chamotte earths, these calcined clays remain unfinished raw materials. Their high purity supports consistent mullite development in end products.
Duty Rate — China → United States
35%
Rate breakdown
9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
Import Tips
• Provide XRD analysis showing mullite precursors; declare as 'calcined clay grog' explicitly; ensure no pre-firing to mullite phase to stay in 2508