HUUUUGE. And AAAAWWWESOOOOME!!! This marble is CRAZY. A pure wonderland of glass exploration as you stare down into the jagged depths of this vortex. I've never seen anything remotely like this marble, I have enjoyed my short time with it immensely. There are so many nooks and crannies to explore down in there, such interesting glass, really a study of glass itself. Tim really honed his copper electroforming skills with the backside of this one, so clean and cool looking, like some post-industrial gadget of some kind. I love the rivet lines, and the window lets in light for an added bonus while you're studying this marble. You've gotta see this in hand, this one will be a true conversation piece for your collection!!