Very nice looking vase Marcel! Be advised, polyurethane will not make the inside waterproof for very long. Water will eventually penetrate the poly. I would Use a two part epoxy for that.
thanks Dan, went to the paint store and asked if the poly was ok for it and they said it was.....
they use the poly on wooden boats as well.
now you say this I might consider buying some.
guess my wife wont put on flowers for weeks right, just a couple of days.
let you know