British glassmaker replicates ancient Roman color changing glass

British master glassmaker Lisa Hollands successfully recreated the chemical recipe used by the Romans to produce a unique green glass that appears red when light shines through it.

The discovery explains the production of the Lycurgus cup, a fourth-century artifact known for its shifting colors and intricate mythological scenes. While researchers suspected for decades that gold and silver traces caused the color change, some experts in 2007 argued the effect might be accidental.

Hollands proved the effect was intentional by replicating the ancient technique. Using this recipe, glass artist Elliott Walker created a modern version of the Lycurgus cup. This new piece will be displayed at the Festival of the Mind in Sheffield until 15 November before moving to the Turner Museum of Glass at the University of Sheffield.