WCO Explanatory Notes reproduced for reference. © World Customs Organization. Verify against official WCO publication.
74.02 - Unrefined copper; copper anodes for electrolytic refining. This heading covers : (I) Black copper. It consists of an impure form of copper produced by smelting oxidised cop er ores or impure copper scrap, usually in a blast h a c e . The copper content varies in the range of approximately 60 to 85 % by weight. WI ely, usually (2) Blister copper. It consists of an impure form of copper roduced by blow.-g air through molten co er matte. During the conversion process, sulp ur, Iron and other mpurihes are oxidised. copper content is normally about 98 % by weight. E fie (3) Copper anodes for electrolytic refining. Copper partially refined by corn lete fusion is cast into anodes for further refining by electrolysis. These anodes are usu y in the form of slabs cast with two lugs for suspending them in the electrolytic refining tank. They should not be confused with anodes for electro-copper-plating (heading 74.19).
1.- In this Chapter the following expressions have the meanings hereby assigned to them : (a) Refined copper Metal containing at least 99.85 % by weight of copper; or Metal containing at least 97.5 % by weight of copper, provided that the content by weight of any other element does not exceed the limit specified in the following table : TABLE - Other elements Element Limiting content % by weight Ag Silver 0.25 As Arsenic 0.5 Cd Cadmium 1.3 Cr Chromium 1.4 Mg Magnesium 0.8 Pb Lead 1.5 S Sulphur 0.7 Sn Tin 0.8 Te Tellurium 0.8 Zn Zinc 1 Zr Zirconium 0.3 Other elements*, each 0.3 * Other elements are, for example, Al, Be, Co, Fe, Mn, Ni, Si. (b) Copper alloys Metallic substances other than unrefined copper in which copper predominates by weight over each of the other elements, provided that : (i) the content by weight of at least one of the other elements is greater than the limit specified in the foregoing table; or (ii) the total content by weight of such other elements exceeds 2.5 %. (c) Master alloys Alloys containing with other elements more than 10 % by weight of copper, not usefully malleable and commonly used as an additive in the manufacture of other alloys or as de-oxidants, de- sulphurising agents or for similar uses in the metallurgy of non-ferrous metals. However, copper phosphide (phosphor copper) containing more than 15 % by weight of phosphorus falls in heading