The Lycurgus Cup

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c. 350 · Roman Empire · Europe · Science

Roman glass that changes colour: 4th-century nanotech

In reflected light the cup is green; lit from behind it glows red. The secret is gold and silver particles only tens of nanometres across mixed into the glass, though the Roman makers can hardly have known why it worked.

State: Roman Empire

Wikipedia (Russian) · Wikipedia (English) · 4th century

Did you know

The Romans used nanotechnology without knowing it. The 4th-century Lycurgus Cup is green in reflected light and red when lit from within, thanks to gold and silver particles just tens of nanometres wide. Share →

Meanwhile around the world (±25 years)

Alive at the time

• Ezana of Axum (aged 30)
• Anthony the Great (aged 99)