Glass Cabochons, 30mm Round, Eight PiecesThese glass cabochons will fit into bezel trays with the corresponding tray size. The glass magnifies the paper or other material that it is placed on and makes beautiful Jewelry, magnets, or other decorations. See below for directions on how to use these. Shape: Round Size: 30mm Diameter Thickness: 7mm Number of Cabochons in Package: Eight Simply put a few dots of Diamond Glaze on the bottom of the glass cabochon, and press down firmly on the paper