26 OPTICAL GLASS IN ANY FORM (SLABS, BLOCKS, STRIPS, GOBS, DISCS, PLATES, PRISMS, WINDOWS, PRESSINGS, RODS; FILTER GLASS INCLUDING ABSORPTION GLASS AND INFRARED MATERIALS; MIRROR BLANKS INCLUDING GLASS CERAMIC MATERIALS; RADIATION SHIELDING GLASS; GLASS FOR LASER AND FIBER OPTICS AND INTERFERENCE FILTERS