Attempts at distinguishing objects made from native copper by the presence (or absence) of particular impurities have been shown to be unreliable. The use of metallurgical grain size as a determining factor is also open to possible ambiguities since the grain size may vary greatly from one native copper specimen to another. Hardness as a parameter, dependent as it is on impurities, also will not constitute a distinguishing measurement. In order to determine whether or not there are metallographic features that would serve to identify objects made of native copper and if so, at what point in its treatment would that distinguishing factor be obscured, some native copper was studied metallographically, (1) in its untreated state, (2) after varying amounts of cold hammering. (3) after recrystallization, (4) after remelting and, (5) after rehammering. It has been concluded that there are no metallographic features that identify native copper objects unambiguously. If the occasional native copper contains uncharacteristically long annealing twins, the identity of these twins can no longer be distinguished from strain markings produced by about 70 percent thickness reduction. Comparisons between North American Eskimo coppers with copper from Palestine are discussed. -- AATA