Colour Changing Chalice

Not only a tongue twister, this colour changing chalice left scientists in knots as they struggled for decades to understand how it worked. Known as the Lycurgus Cup, it is both the only  figural example of a type of vessel known as a ‘cage-cup’ and the only complete Roman glass object made from dichroic glass.
Lycurgus Cup is made of dichroic glass and appears jade green when lit from the front. © Trustees of the British Museum

Lycurgus Cup (4th century AD) is made of dichroic glass and appears jade green when lit from the front. © Trustees of the British Museum

What is so fascinating about this chalice is that is changes colour depending if light is shone from the front or back. This colourful secret intrigued scientists and it wasn’t  until 1990 they attributed this colour change to nanotechnology.
The Roman artisans “impregnated the glass with particles of silver and gold, ground down until they were as small as 50 nanometers in diameter, less than one-thousandth the size of a grain of table salt.”  When light hits the metal nanoparticles, the electrons in the metal are excited in ways that alter the colour depending on the observer’s position.
Lycurgus Cup is made of dichroic glass and appears blood red when lit from the back. © Trustees of the British Museum

Lycurgus Cup is made of dichroic glass and appears blood red when lit from the back. © Trustees of the British Museum

I stumbled upon this beautiful chalice in a recent Smithsonian Magazine article as it seems scientists are tamping into this 1,600-year-old “technology” to create “super­sensitive new technology that might help diagnose human disease or pinpoint biohazards at security checkpoints”.
If you’re like me and want to see the real thing you need to get yourself down to the British Museum.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s