Micronized Mullite Flour from China
Micronized mullite flour (D50 <5μm) serves as a fine filler in technical ceramics and casting slips. Remains under HTS 2508.60.00.00 as processed mullite powder, not chemical preparations.
Duty Rate — China → United States
37.5%
Rate breakdown
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)
9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China
Import Tips
• Submit particle size distribution (laser diffraction) confirming flour specification
• Ensure no organic additives; pure mullite maintains mineral classification