IRON AND SULFUR RELATED COLORS IN ANCIENT GLASSES

Roman glass found at Jalame, in Western Galilee, and dating from the fourth century A.D., shows a variety of colors ranging from aqua blue to green to amber. It was found that the glasses are quite reduced and that the colors arise from absorptions by Fe²⁺ and a ferri-sulfide chromophore. Small amounts of colorless and purple glass, which had been oxidized by adding MnO₂, were also found.