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%Except for products described in headings 9903.05.85–9903.05.93, articles the product of Canada, as provided for in U.S. note 52 to this subchapter
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