How do you tell if stained glass is Tiffany?

To tell if stained glass is Tiffany, first examine the piece and look for a maker's mark. Tiffany Studios changed its hallmarks many times over the years. By comparing the marking on your piece to images of hallmarks found on authentic items shared on trustworthy websites, you can begin to identify your glass. The base can provide an additional clue if your stained glass piece is a lamp. Many Tiffany lamps have a gray metal ring located under the cap. If you spot one, your piece may be made by Tiffany. Because there are many reproductions on the market, it is often wise to have a certified appraiser or knowledgeable antique dealer assist with the identification process. Find a range of Tiffany glass on 1stDibs.