Instructions
Learn about antique cut glass items and identification by getting a copy of the "Standard Cut Glass Value Guide."
Turn the glass item over and look for a manufacturer's signature on the bottom of the item. Not all items will have a signature, but Waterford (a primary producer of Irish cut glass) typically marked its items.
Look for favorite designs by Waterford cutters on the glass item. Pointed ovals that alternate with lozenges on the decanter is one such design.
Find pieces with intersecting diamond shapes, a favorite early Irish design. The diamond shapes will produce lots of light and sparkle.
Ask for the original bill of sale or certificate from the item, if possible. As the artists traveled between England and Ireland, so did their skills and knowledge, making the point of origin of the item more difficult to determine if the glass piece is English or Irish.