The idea was to use bars of two or more different types of steel, or iron
steel, one having less carbon content, and forge them together into a
single bar. This was done by heating, twisting and hammering as needed, and
then folding the bar, hammering and forging it again. The process was
repeated a few more times. The result was a bar with layers of steel of
different types producing the wavy lines and patterns visible due to the
difference in chemical composition between the different bars used.

The technique was first called ‘pattern welding’ and was known to several
cultures. The Japanese had been using it to manufacture their swords since
1100 AD, and the Vikings and Celts around 600 AD. By 1570, it was used to
manufacture gun barrels in India. The Damascus techniques had spread to the
Ottoman Empire and later to Hungary and Spain by the 1650s. The defeat of
the Turks at the siege of Vienna in 1683 yielded thousands of captured
pattern welded barrels for examination. This accelerated the manufacturing
of pattern welded barrels in Europe. By 1700, the Belgians were producing
pattern welded barrels in Liège, and in the early 1800s, the technique was
used in England to produce high quality sporting barrels.

The challenge in producing the dial of this limited series was the process
of cutting the dials out of the round barrels. This involved several
operations that took place in London and in Geneva, at F.P. Journe’s own
dial makers, “Les Cadraniers de Genève”.