This cold blacking process is known in the English language as "blueing" or more recently as chemical blacking or chemiblacking, whilst the hot oxide process is known as black oxidising or black oxide. Illogically many Europeans have adopted the old French term, "brunissage" for the name of the process, which literally translated means 'browning'. In German it is "brünierprozess" or "brünierung" and in Scandinavian "brunering". The Spanish have a more colourful slant to their term "pavanado", which is a very similar word to peacock with its magnificent deep iridescent purple blue plumage.
With the growth in popularity of the Blackfast process during the last 10 years and its ubiquitous use throughout Europe there has been the development of yet one more name for the process... Blackfasting!!!