2510

Analysis

Heading 2510 of the Harmonized Tariff Schedule covers natural calcium phosphates, natural aluminum calcium phosphates and phosphatic chalk. It divides into 2 six-digit subheadings and 2 eight-digit tariff lines, with 2 ten-digit statistical suffixes below them.

Every one of its 2 tariff lines is duty-free at the general rate, so classification within the heading affects statistics and Chapter 99 measures rather than the base duty.

The largest subheadings are 2510.10 (unnamed, 1 line) and 2510.20 (unnamed, 1 line).

By Census's concordance, most of its statistical lines are made by Other Nonmetallic Mineral Mining and Quarrying (21239). Those are the NAICS industries a US producer of these goods would report under.

Its median rate of duty-free sits at the 46th percentile of the headings in chapter 25.

The heading text decides whether a product belongs here at all (General Rule of Interpretation 1); the subheadings and lines below it only apply once that is settled. Section and chapter notes can override the heading wording, so read them for borderline goods.