Supersulfated Cement Powder from China
Though related to slag cements, certain supersulfated formulations with unique gypsum-calcium sulfate ratios qualify as 'other' under HTS 2523.90.00.00. This hydraulic cement develops strength through sulfate reactions, suitable for marine structures. Excluded from pure slag cement (2523.28) by composition specifics.
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
• Submit sulfate and slag content certificates; >85% slag shifts to 2523.28
• Label clearly as hydraulic to prevent confusion with non-hydraulic limes (2522)
• Watch for EU origin certificates as supersulfate imports often face specific trade agreements