University Frames offers two options for your school's official seal or logo: foil embossing or an engraved medallion. Both measure approximately 1.5 inches in diameter. The medallion is then inserted into an opening cut into the matboard to ensure that it lays flush with the matboard. The medallions are offered in two different finishes: 22-karat gold or rhodium plating. Rhodium is a precious metal worth substantially more than silver, and will hold its luster without tarnishing.