The split is at 0.5% phosphorus by weight for nonalloy grades: pig iron at or below that threshold falls under 720110, while pig iron exceeding 0.5% phosphorus falls under 720120. Alloy pig iron and spiegeleisen (which contains 6–30% manganese) are classified together under 720150 regardless of phosphorus level.

Yes, pig iron falls within the scope of Section 232 measures on steel and iron products. The applicable rate and any country-specific exemptions or quota arrangements depend on the specific tariff line and the country of origin, so importers should verify current proclamations and any bilateral agreements before finalizing sourcing decisions.