We all understand that pattern welded BLADES have a different fabrication process than BARRELS.
Blades were produced primarily by folding and hammering of the laminate, occasionally with some twisting, and then grinding. Modern blades have incredibly creative patterns from the twisting and grinding.

This is an x-ray of a pattern-welded sword, French, Lorraine, Merovingian period, sixth century. The central portion clearly has a crolle pattern

[Linked Image from photos.smugmug.com]

Blade history here
https://docs.google.com/document/d/1p97fInNIiSMjHuMRzJp2pHmQ1QPwPDeJECNbNKzInI4/edit

Wootz, which may have been what the first pattern welded smiths were trying to reproduce.
https://docs.google.com/document/d/13X5cxrij91Q_W-46bxP188B_axDKBWT5Mc5yHePegh0/edit

[Linked Image from photos.smugmug.com]

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