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Diatomaceous Earth Firebrick from Japan

A high-temperature resistant brick made from diatomaceous earth (kieselguhr), a siliceous fossil meal, shaped and fired for use in industrial furnaces and kilns. It falls under HTS 6901.00.00.00 as a ceramic good specifically of siliceous fossil meals, providing superior insulation due to its low thermal conductivity.

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

Verify composition certificates confirming siliceous fossil meal content like kieselguhr to avoid reclassification to clay-based bricks

Provide firing process documentation proving temperatures exceeded 800°C per Chapter 69 notes

Check for uniformity in density and absorption to prevent disputes over 'similar siliceous earths' classification