Ancient Germanic smiths used a technique known as pattern welding, by which a blade was forged from several rods twisted and hammered together when in fusion. This process not only makes the resulting blade stronger, but it also gives it a very distinctive patterned surface – hence pattern welding – which inspired the poet of the poem Beowulf to coin the phrase ātertānum fāh (stained with poisoned twigs) to describe its malevolent beauty.