Ancient Romans Were Nanotechnology Pioneers
The Lycurgus Cup, a 1,600-year-old Roman chalice housed in the British Museum, had baffled scientists ever since the piece was acquired back in the 1950s. When lit from the front the chalice appears as a beautiful jade green. Oddly, when lit from the back it turns a bright blood red. The mystery was solved in 1990 when researchers were able to view broken shards of the cup. That was when they discovered that the Romans had been working with nanotechnology.
The Roman artisans had infused the glass with tiny particles of silver and gold that had been ground so finely that they measured as small as 50 nanometers in diameter (one nanometer - one billionth of a meter).That is less than one thousandth the size of a grain of salt. The precise mixture of the metals demonstrates that the Romans knew exactly what they were doing.
When light hits the cage cup the electrons in the metal particles begin to vibrate in a way that makes it turn different colors to the observer. The scientists believed that the cup would also react in the same way when filled with different liquids. They couldn't risk using different liquids into the chalice itself they designed an experiment to test the same properties on a plastic plate the size of a postage stamp. It was dotted with wells that they filled with gold and silver and then different liquids -- water, oil, sugar water, and salt water. Each different liquid took on a different color. This color also changed for the varying strengths of salt or sugar. This prototype turned out to be 100 times more sensitive than current technology to detect such variations..
The Lycurgus Cup is a relic from the fourth century was named for the mythical King Lycurgus. His image is depicted on the chalice entangled in grapevines. It is thought that it showed him this way because of a transgression he had made against Bacchus, the Roman god of wine. He had tried to kill Ambrosia, a follower of the god. The god turned her into a vine and she wound her way around the king and eventually strangled him.
The cup is also a rare example of what is called a cage cup or diatretum. This is a process in which the glass has been cut and ground down to leave a decorative sort of "cage" at the level of the original surface of the glass.
When it comes to the Lycurgus Cup perhaps it is true what they say: Everything old is new again. This old thing is certainly giving researchers a chance to learn a whole bunch of new tricks.