Technical Grade Ammonium Tungstate from Mexico
Technical grade ammonium tungstate (85-90% purity) is used in fabric fireproofing and leather tanning. It qualifies as an ammonium tungstate salt despite lower purity, as Chapter 28 note 1(a) permits impurities in chemically defined compounds.
Duty Rate — Mexico → Canada
0%
Import Tips
• Clearly state the purity range (85-90%) on the commercial invoice to avoid valuation disputes
• If the product contains impurities that affect its use, provide a full chemical analysis to support classification
• Verify whether the product meets Canadian workplace safety standards for the stated end-use