Real heavy thick chunk of light aqua glass. Crude with many small bubbles. For truth in photography, I rotated it so you can see the only damage. About a 1/2" base flake to the left of the mold line. Of course, since it has no skirt embossing, you can turn it any way you want. For more information about this piece, see http://www.insulators.info/articles/beaver.htm Should sell fast at $100 plus shipping.