I did this with some Black Mountain Birch wood that I hand carried from atop Black Mountain (highest point in Kentucky) near Lynch KY where I worked as a Coal Miner for 10 year. I have some Original coal from the #32 mine that I worked in and used some chips to insert into the drilled holes. I have some pics somewhere and will post soon.
I found the turned barrels of the 32 Mine Coal and Black Mountain Birch but haven't assembled the pen yet, I did take a snapshot of the sign on top of the mountain which is the KY/Va state line. You can stand in the road and have one foot in KY and the other in Virginia. I added some other new pens I created in the past week.