Nepheline Syenite for Fiberglass from Mexico
Low-boron nepheline syenite for E-glass fiberglass reinforcement production. Provides stable alumina-silica ratio for fiber durability. HTS 2529.30.0050 'other' nepheline selected for boron <50ppm specification.
Duty Rate — Mexico → United States
10%
Rate breakdown
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• ICP-MS analysis confirming B2O3 <50ppm prevents borosilicate confusion
• Fusion temp 1450-1480°C verified by thermal analysis
• Silica/alumina ratio 4.5-5.0 maintained within natural nepheline range