A system and method for authenticating a multi-sided die by viewing the die under invisible ultraviolet light. A die body has a plurality of sides of substantially equal area. A plurality of visible markings for indicating a roll of the die are disposed on the die sides. One or more of the markings include a substance which visibly reacts with invisible ultraviolet light. One or more authentication marks including a substance which visibly reacts with invisible ultraviolet light are arranged in a selected pattern on one or more of the die sides. A position of the authentication mark or marks in the selected pattern corresponds to the visible marking having a substance which visibly reacts with invisible ultraviolet light. An overlay key correlates the position of the authentication mark with the visible marking.