Zircon-Mullite Refractory Block from Japan
Zircon-mullite refractory blocks are fired ceramic construction blocks blending zircon and mullite for glass furnace crowns and regenerators. They resist alkali corrosion and thermal cycling. HTS 6902.90.50.20 applies to these other refractory ceramic blocks.
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
• Submit mineralogical analysis to prove inorganic nonmetallic fired composition per Chapter 69 notes
• Ensure blocks are not cermets (8113) by confirming no metallic binders
• Pair with end-use declarations for furnace construction to prevent reclassification as parts