Presently described are retroreflective articles, such as pavement markings, that comprise transparent microspheres partially embedded in a (e.g., polymeric) binder. Also described are (e.g., glass-ceramic) microspheres, methods of making microspheres, as well as compositions of glass materials and compositions of glass-ceramic materials. The microspheres generally comprise lanthanide series oxide(s), titanium oxide (TiO.sub.2), and optionally zirconium oxide (ZrO.sub.2).