Many of the moulds in which weapons and implements were cast have been preserved. Open moulds sufficed for flat axes; but the more difficult operations of casting palstaves and socketed celts required that the moulds should be made in halves. All the open ones that remain were of stone; many others, however, were doubtless formed of more perishable materials, such as clay or compact sand. Bronze moulds were also used; but the only specimens which have been found were for palstaves, socketed celts, and gouges. There is a bronze mould in the British Museum that was itself cast in a mould of clay, formed round a model palstave, and attached to it by string, which was of course reproduced in the metal. Leaden celts have once or twice been met with, which of course would have been useless as cutting tools; and it is probable that they were intended simply for making moulds of clay or sand. Bronze moulds were costly, and would soon wear out. It has been suggested therefore that, just as a printer uses in his press not his original wood-block but an electrotype copy, so the bronze-founder generally reserved his bronze moulds for making leaden models from which any number of clay moulds could be formed.[587] Sockets were produced by means of clay cores, which were inserted in the moulds. Socketed celts have so often been found in hoards with the cores remaining in them that we may reasonably conclude that they were bartered by the bronze-founders in this state, and that, as in the Neolithic Age, the purchasers finished them with their own hands.[588] The hammers and anvils which were used in the final stage of manufacture were commonly stone, though a few light bronze hammers have been unearthed; and the decoration was applied by means of punches.[589]
The patterns with which weapons were decorated are worth noticing even by those to whom archaeology for its own sake makes no appeal. Daggers and flat or slightly flanged celts were incised with rectilinear figures and chevrons only:[590] winged celts, palstaves, socketed celts, and spear-heads have similar designs in a few instances,[591] but for the most part they are ornamented with concentric circles. The significance of these facts will become apparent when we come to deal with certain chronological questions relating to the Bronze Age.[592]