2508.40.01

Analysis

HTS 2508.40.01 covers other clays (not including expanded clays of heading 6806), andalusite, kyanite and sillimanite, whether or not calcined; mullite; chamotte or dinas earths… under heading 2508 (other clays (not including expanded clays of heading 6806), andalusite, kyanite and…). US Customs collects import statistics for it under 3 ten-digit suffixes, reported in metric tons.

The normal trade relations rate here is zero, shared by about 91% of the 78 tariff lines in chapter 25, a useful check when a neighbouring dutiable line is a candidate. Free here means free of the base duty only: origin-specific Chapter 99 duties such as Section 301 can still be owed.

Census statistics map these goods to NAICS 21232 (Sand, Gravel, Clay, and Ceramic and Refractory Minerals Mining and Quarrying), an industry of 2,617 US establishments employing 36,740 people. That concordance is how imports of this line are compared with US output.

The ten-digit suffixes separate common blue clay and other ball clays and decolorizing earths and fuller's earth. The duty is the same across them; the suffix matters for statistics, licensing and some quotas, and an entry needs all ten digits.