The Lycurgus Cup, from the 300s CE, looks jade green in normal light. Light it from inside and it glows red. Scientists found tiny particles of gold and silver in the glass, a kind of nanotechnology.
Truth label: Established. Strong evidence and broad agreement among experts.
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How small?
The particles are about 70 nanometres across, around a thousandth of the width of a human hair.
Accident or skill?
The Romans could not have understood the physics, but they clearly knew how to repeat the effect.
Learn
- Where to see it. It is on display at the British Museum in London.
Test yourself
What colour does the cup glow when lit from inside?
Red. Light passing through turns it red.
Sources
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