Scientists Recreate the Lycurgus Cup's Ancient Roman Nanotech

Researchers at the University of Sheffield have for the first time reproduced the dichroic glass of the 4th-century Lycurgus Cup: 50–80 nm silver-core, gold-shell nanoparticles shift its color from green to red. The glass self-strikes during annealing, requiring no complex heat treatment.

• Particles are 50–80 nm with a silver core, gold shell and some copper
• Gold-to-silver ratio in the nanoparticles is about 3 to 7
• The glass shifts from green to ruby red under backlight
• Blown Away winner Elliot Walker made a modern replica of the cup