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Diatomaceous Earth Firebrick from Canada

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 — Canada → United States

10%

Rate breakdown

9903.05.2910%Section 301 (forced labor) — additional 10% ad valorem on products of Canada

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