Optical Grade Calcium Carbonate from Japan
High-purity, low-birefringence calcium carbonate crystals for optical polishing compounds and lens manufacturing aids, under HTS 2836.50.00.00. Synthetic single crystals available.
Duty Rate — Japan → United States
12.5%
Rate breakdown
9903.05.4912.5%Section 301 (forced labor) — Japan (col1 rate < 12.5 percent): MFN < 12.5% → total duty capped at 12.5%
Import Tips
• Provide X-ray diffraction confirming calcite crystal structure
• Test for inclusions (<10 ppm) affecting optical clarity
• Package in inert atmosphere to prevent CO2 absorption/hydration