The wood has been stabilized which is why it polishes up so shiny when working it. Normally hackberry is pretty soft and not as tight. That said, I may still put a varnish or poly on the inside for extra protection. In other uses I have wood bowls that are raw and completely unfinished that I use wet for short periods of time (less than 30 - 60 minutes) and then dump and dry. They do a surprising job of holding water for that duration and not splitting or warping in any major way.Nice work! What will you use to coat the wood?