This marble is a TRUE masterpiece - WOW!!! From Tim's 'Copper-clad Series' comes this magnificent vortex, covered in copper on the backside - with a zipper opening up into the vortex. Let me repeat that - A ZIPPER OPENS INTO THE VORTEX!! Ha haa, how awesome is THAT!! It doesn't really 'open' of course, since it's copper, but you know what I mean. No need to say more, check out those pics!