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Sillimanite Grain for Refractories from China

Sillimanite grains are crushed and sized particles of sillimanite mineral (Al2SiO5) used in refractory castables and ramming mixes. This product falls under HTS 2508.50.00.00 as unprocessed sillimanite, valued for its high melting point above 1600°C.

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

Specify grain size distribution (e.g

3-6mm) in commercial invoices to justify non-agglomerated status

Include thermal expansion test data distinguishing from mullite products

For container shipments, ensure ventilation declarations to prevent moisture absorption affecting classification