Mullite Chamotte Grogs from Japan
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 — Japan → United States
12.5%
Rate breakdown
9903.05.4912.5%Except for products described in headings 9903.05.85–9903.05.92, articles the product of Japan, with an ad valorem (or ad valorem equivalent) rate of duty under column 1 less than 12.5 percent, as provided for in U.S. note 52 to this subchapter
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)