Copper alloy dagger
The systematic use of copper started at the end of the Neolithic era and transformed the nature of war. One of the most remarkable changes was the introduction of specialized offensive weapons, such as daggers. The earliest Aegean daggers were short (< 10 cm), had triangular shape and were probably attached to a wooden staff, like spears. In the Early Bronze Age, daggers became longer and obtain a central rib which increased their strength and efficiency. They were cast in moulds and then hammered to obtain sharp cutting edges. At the end, a handle made of wood of other organic material was rivetted on the shoulder. In the photo, you can see four rivet holes, which were used for fastening the handle to the blade.
Most weapons of that period were made of a copper-arsenic alloy, which was naturally available in the Cyclades and other parts of the Aegean. In the later part of the 3rd millennium BC, a new alloy of tin-bronze made its appearance. The new alloy was much more durable and effective. The lack of exploitable tin deposits in the Aegean meant that the material should be imported from elsewhere. This directed Aegean societies towards maritime trade and brought about major economic changes.