Antiqued Silver Plated Pewter. 22mm Spiral Square Toggle Clasp. Lead-free TierraCast Pewter. . This lead-free pewter item is plated with fine Silver in an antiqued finish. An unusual shape for a modern look. Quantity: 1 Set. Measurement: 22mm at widest point (diagonally,) 22mm long, 19.5mm Square. 2mm thick. Bar is 24.5mm long. TierraCast Pewter is made in the USA, using Lead Free Pewter that exceeds both the CPSC standard and the new California law regulating children's jewellery content. Although all pewter contains trace amounts of lead, the term "lead free pewter" is used to describe pewter that meets the stringent CSPC standard of less than.05% (or 500 parts per million) lead content in pewter.