http://www.lampworketc.com/forums/sh...hlight=Devardi
I work with this glass a lot. These beads are approx. 12mm in diameter. The only thing you need to do is work it cooler than other glasses. I have never pre-heated my rods... just work it a little bit further out from the flame at first. The thread above will show numerous beads made with Devardi.
Jack