I think this effect is called an "oopsie"
but we no doubt have a lot more to learn about lopins, patterns, and staining methodology.
There
IS a "Barber's Pole"; Two Iron Crolle Damascus Twist, Laminette Double, or
Doppelter Laminett with two crolle rods with an "on edge" Twist rod on each side.
Obviously the "twisted around a pole" appearance is from the patterns, not the differential coloring
Bro. Steve figured out the "Damascus Twist" lopin of the Batavia barrel
The 'end on' of a ribband can be seen in the middle here
I suspect the pattern of the dark stained steel is just by chance
Unlikely anyone has done more restorations today than Paul Stevens. You might ask his opinion
barrelfinishers@gmail.com
https://m.facebook.com/StevensAndJohnson/