You got me going through the house looking for "Purple Overtones"
Didn't use any Black Walnut in the house 20 yrs ago, so all Black Walnut experience has been in last 5 yrs.
Didn't notice any in the KD stuff from Atlantic Hardwoods!
It was All in the 500bf we got from an Amish friend up North that he got in a truckload from a PA community and the Walnut was PAD in a barn.
(Jonas is a furniture builder in Easton,Maine...and when the 3 communities need wood, they contact the PA communities for a truckload. As a favor he got us 1,500bf of Cherry/Maple/Walnut)
The Purple is only where the Walnut shades to almost Black, and Really only shows up for me when sanded to 600G and several coats of oil finish under halogen or direct sunlight....
Maybe it's just my eyeballs and imagination
Turns out almost as impossible to take a picture of as "Fugitive Purples" in an Opal!
(It's really just an overtone anyways).
Never even had a hint of it in all the KD thin Black Walnut we got from Ocooch.
I'VE had people drop the board feet where knots/splits/holes caused some CRAZY grain patterns too!
UNTIL they found out that was what I WANTED
GREAT back story and details Ted!!