Heat-Treated River Flint Shingle from Mexico
Durable flint pebbles heat-treated for improved weathering resistance, used in concrete aggregates and road metalling. The thermal processing enhances bonding properties without altering basic classification. Covered by HTS 2517.10.00.15 including heat-treated shingle and flint.
Duty Rate — Mexico → United States
10%
Rate breakdown
9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico
Import Tips
• Document heat treatment temperature/time to prove doesn't constitute 'worked' processing under chapter notes
• Flint's high silica content requires proper dust control certification for handling
• Distinguish from decorative fire pit flint by specifying construction aggregate end use