Explanatory notes
… mixtures, of a kind used for the extraction of arsenic or those metals or for the manufacture of their chemical … This heading covers slag, ash and residues ( other than those of heading 26.18, 26.19 or 71.12 ) containing metals, … copper, nickel or cobalt mattes ( Section XV )) and slag or dross, for example those rich in copper, zinc, tin, lead, …