produce a pattern of randomly positioned blobs of color. Some modern bladesmiths have taken pattern welding to new heights, with elaborate applications of traditional pattern welding techniques, as well as with new technology. A layered billet of steel rods with the blade blank cut perpendicular to the layers can also produce some spectacular patterns, including mosaics or even writing. Powder metallurgy allows alloys that would not normally be compatible to be combined into solid bars. Different treatments of the steel after it is ground and polished, such as bluing, etching, or various other chemical surface treatments that react differently to the different metals used can create bright, high-contrast finishes on the steel. Some master smiths go as far as to use techniques such as electrical discharge machining to cut interlocking patterns out of different steels, fit them together, then weld the resulting assembly into a solid block of steel. Etymology The term 'pattern welding' was coined by English archaeologist Herbert Maryon in a 1948 paper: "The welding of these swords represents an excessively difficult operation. I do not know of finer smith's work... I have named the technique ‘pattern welding’... Examples of pattern-welding range in date from the third century to the Viking Age." See also Bulat steel, a Russian crucible steel Damascus steel, a steel used in swordmaking during the medieval period Forged in Fire a History channel competitive television show on forged knife and sword making Hamon (swordsmithing) Japanese sword construction includes a specific form of pattern welding. Mokume-gane, a similar technique, often for precious metals, used to produce decorative pieces Wootz steel, an Indian crucible steel References Sources External links Bladesmith Kevin Cashen's page on pattern welding Ancient carburisation of iron to steel: a comment Mediæval Sword Virtual Museum, which contains close-up images of Viking swords, showing the pattern welding structures. Welding Steelmaking Blade weapons