Sheffield’den bir uzman, bir Roma kadehinin renk değiştiren camını yeniden üretti

The Lycurgus Cup, a fourth-century Roman chalice in the British Museum’s collection since 1958, looks opaque green when light reflects off it but turns red when light passes through it. The effect is thought to come from tiny particles of silver and gold embedded in the glass, which block or scatter light. The principle has long been understood, but reproducing it proved hard. Now Lisa Hollands, who works on glass technology at the University of Sheffield, has developed a recipe that reliably creates the effect while relying on ingredients that Roman artisans could have obtained. Working with archaeologist Caroline Jackson, she recreated a Roman-style base glass, then tested furnaces, oxygen levels and ingredients, including sugar. Ian Freestone of University College London notes that the colour depended heavily on where the glass sat in the furnace, suggesting the Romans may have struggled to control it. The work could aid new photonic materials and the safe storage of radioactive waste in glass.