Brass Oxide Finish Pewter. 5.7mm 'Tiffany' Bead Caps. Lead-Free TierraCast Pewter. From TierraCast's new Alternatives Collection, brass oxide finish over lead-free pewter. These are not brass stampings, but strong and beautiful castings made with TierraCast's attention to quality. This muted finish is a perfect complement for vintage-insp...