poplar bark from a mature tree. Pieces shown are over 12" long, 2-3" wide. Probably not what you're looking for, JJ. It's real easy to find storm downed or cut down poplar around here, and I can look for some of the smooth light-greenish bark, if you want.
If anyone wants some, it would be 'cost of shipping' to you. I've got at least 4 times what's shown in the picture. Nice reddish brown color with laminations, as seen in the pieces that I sliced on the band saw. I made some fly rod grips out of it, and they were really pretty, but also too brittle, unlike oak bark, i.e. cork.