The question as to the sources of metals in ancient Greece, as also in the whole of Europe, in the bronze age, has for some time exercised archaeologists. Apart from certain regions, little exploration has been carried out with regard to ancient mines, and there has especially been a tendency to take a long view in archaeology, and to connect across considerable distances regions where metal is known to have been worked in early times with regions where there is no information on the subject. But early mines are often hard to detect, as either the ore was completely exhausted, or the early workings have been obliterated by later peoples. There is, however, room for much careful investigation in this field, and metal being one of the most important objects of early commerce, the discovery of the sources used should throw a considerable light on this extremely complicated subject.