<P> 3rd millennium BC copper metalwork is attested in places like Palmela (Portugal), Cortes de Navarra (Spain), and Stonehenge (United Kingdom). However, as often happens with the prehistoric times, the limits of the age cannot be clearly defined and vary with different sources . </P> <P> The theory that metallurgy was imported into Europe from the Near East has been practically ruled out . A second hypothesis, that there were two main points of origin of metallurgy in Europe, in southern Spain and in West Bulgaria, is also doubtful due to the existence of sites outside the centers of diffusion where metallurgy was known simultaneously with, or before, those in the' original' nuclei, such as Brixlegg (Tyrol, Austria), while sites closer to the supposed origins of metallurgy, such as in the north of Spain, show fewer metal artifacts than sites in the south and practically no evidence of production (Perez Arrondo 1986). </P> <P> Currently, the general opinion is that the development of metallurgy took place independently in different places, at different times, with various techniques . One fact that supports this interpretation is that, although the final products (beads, rings, sickles, swords, axes, etc .) are quite similar throughout Europe, the method of production is not . Thus the use of crucibles was the technique utilized in the south of Spain, whereas central Europe employed a slagging process, but Cabrierés (France) used a primitive oxidizing non-slagging process (Bourgarit, et al. 2003), while in the British Isles the absence of debris, slag or ceramic suggests another technique (Craddock 1995). </P> <P> Consequently, the way in which metallurgy was initiated differs considerably depending on the region . There are areas in which copper seems to play a crucial role (i.e., the Balkans), whereas other areas show no interest in it at all . Then there are societies that use copper artifacts but do not practice metallurgy (Mohen 1992; 71), and there are other ones that fully adopt some of the cultural innovations but ignore the rest . One example of the latter is Basque country in northern Spain, where splendid large dolmens are present along the Ebro river, but metal is rather infrequent, and when it does appear between the trapping, it is more often bronze or arsenical copper than copper (Cava 1984). </P>

When did copper working first appear in europe