Kronon Magic: These barrels are made out of a glass called Kronos that is magic! It has so many colors that it changes into and it is irridescent too. It makes a very earthy looking bead. The beads are approximately the following: The 3 middle barrels are 16mm x 12mm a little here a little there the 2 end ones are 14mm x 11mm All of these beads are made in my new studio in Pflugerville, Texas by me a self representing artist, SRA L54. All my beads are annealed in a digitally controlled kiln for lasting beauty, strength & durability. I use Moretti/Effetre, Vetrofond, Bullseye, ASK 104, CIM, Boro and Double Helix glass and the beads are made on a 1/16 mandrel unless noted otherwise. Your satisfaction is guaranteed. If for some reason you are not satisfied with your beads you may return them for a refund minus the shipping. I always want to make my customers happy with what they purchase.