The Lycurgus Cup: a 4th-century Marvel of Roman Glass
Via Smithsonian Magazine
Summary
The Lycurgus Cup is a 4th-century Roman glass chalice that appears jade green when lit from the front but shifts to a glowing blood-red when light passes through it from behind. Held at the British Museum, the cup depicts King Lycurgus of Thrace ensnared in grapevines. For decades after the museum acquired it in the 1950s, scientists were baffled by its color-changing properties.
The mystery was solved in 1990 when researchers discovered that Roman craftsmen had embedded gold and silver nanoparticles — as small as 50 nanometers across — into the glass itself. The particles interact with light differently depending on the direction of illumination, revealing that Roman artisans were practicing a rudimentary form of nanotechnology roughly 1,600 years before the field was formally defined.
