The Vetulonian sword was crafted by the pattern welding process from five blooms reduced at a temperature of 1163 °C. Five strips of varying carbon content were created. A central core of the sword contained the highest: 0.15–0.25% carbon. On its edges were placed four strips of low-carbon steel, 0.05–0.07%, and the whole thing was welded together by forging on the pattern of hammer blows. A blow increased the temperature sufficiently to produce a friction weld at that spot. Forging continued until the steel was cold, producing some central annealing. The sword was long.