Just for clarity, please note the OP asked about a
shotgun barrel Damascus pattern.
Rosa Damascena
3 Iron "Ferlacher Rosen" Damascus
Parker 'Rose Pattern' Bernard II
"Rosebud" Damascus blade - an entirely different production process involving primarily (the very short version) FOLDING, hammer welding and grinding the laminate; not hammer welding the lopin then twisting and helically welding
Interesting reading regarding BLADE history
https://docs.google.com/document/d/1...nI4/edit?pli=1
BARREL history
https://docs.google.com/document/d/1.../preview?pli=1