Not even sure I'll turn it for a pen. Had an idea and thought I'd give it a whirl. 1/4" thick Cherry in between two 1/4" pieces of Maple. The rest is the playing part. I may reveal what it is if it works out.
It's simple really. I started with a Maple/Cherry blank that I had glued up some time back. Then made a curvy cut longways through the blank with my scroll saw and glued a piece of black fabric in between the two halves. After it cured, I repeated the process three more times.