Mullite Chamotte Grogs from China
Mullite chamotte grogs are fired, crushed mullite particles used as aggregate in refractory brick formulations. Classified under HTS 2508.60.00.00 alongside chamotte or dinas earths as processed refractory materials.
Duty Rate — China → United States
37.5%
Rate breakdown
9903.05.3112.5%Except for products described in headings 9903.05.85–9903.05.92, articles the product of China, as provided for in U.S. note 52 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 firing temperature records (typically >1400°C) confirming chamotte processing
• Document grog sizing (0-5mm typical) and avoid any assembly into shapes
• Watch for reclassification if moisture content suggests hydraulic binders (heading 3816)