2521.00.00.00/High-Calcium Limestone Flux/Japan

High-Calcium Limestone Flux from Japan

High-calcium limestone flux is a coarsely crushed calcareous stone with at least 95% calcium carbonate content, specifically used in blast furnaces to remove impurities during steel production. It falls under HTS 2521.00.00.00 because it is limestone of a kind used for lime or cement manufacture, distinguished by its chemical purity and fluxing properties. This raw material is essential for slag formation in metallurgical processes.

Duty Rate — Japan → United States

12.5%

Rate breakdown

9903.05.4912.5%Section 301 (forced labor) — Japan (col1 rate < 12.5 percent): MFN < 12.5% → total duty capped at 12.5%

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Import Tips

• Verify chemical composition certificates showing high CaO content to confirm classification under 2521.00.00.00 and avoid misclassification as general crushed stone

• Ensure documentation specifies end-use for lime/cement manufacture, as flux properties must be evidenced for duty-free entry in some cases

• Watch for particle size specs; overly processed stone may shift to heading 2522 if not raw flux material