Brian,
The finish is shellac. I agree with you on the fit and finish of the clip.
SMJ1957,
While researching wooden clips I came across an article by Richard Kleinhenz- Wood Through & Through. He had some clips laser cut but also said they could be cut out with a scroll saw. Went with the scroll saw approach. Got a 1/8 " thick piece of maple from Woodcraft, sketched out 8 clips, and cut them out. Took the clips to a benchtop 1" wide belt sander, and the finally a Dremel drum sander. One clip was destroyed in cutting and one was destroyed in sanding. Dyed and finished the clips.
I figured I could cut the slot with a burr in the Dremel, but hand-holding it did not seem like a good idea. Created a Dremel tool holder for the lathe. The post gives me vertical adjustment, the banjo gives me left / right and in / out adjustment, and the wing nut allows me to tilt the Dremel to get it horizontal to the pen on the lathe.
Bob