Blister Copper Buttons from Japan
Small button-shaped castings of blister copper from fire refining, serving as test samples or furnace charge. Under HTS 7402.00.00.00 as unrefined copper ahead of electrolytic refining. Typical 98-99% Cu with gas porosity characteristic of blister form.
Duty Rate — Japan → United States
0%
Rate breakdown
9903.05.860%Universal product exemption (U.S. note 52(b))
Import Tips
• Supply button assay results showing characteristic impurities (O2, S) of fire-refined blister copper
• Document intended remelt use in anode furnaces to confirm unrefined status
• Declare exact button weights; larger castings risk categorization as crude anodes