A jewelry piece is formed with a jewelry body made of epoxy material, defining an outer surface and cast in the shape of a piece of jewelry in the form of a ring, pendant, earring, brooch, bracelet, anklet, necklace, and the like. As a rule, this entails one, or a combination of several filter elements, as for example birefringent filters, as well as etalons. A mobile telephone handset capable of receiving digital broadcast transmissions also includes a loop antenna.