The jade-green chalice with its delicately etched image of King Lycurgus entangled in grapevines is a stunning example of Roman glassmaking. But only upon closer examination can the observer appreciate the true innovation of these Roman artists—their use of nanotechnology.
The 4th century Lycurgus Cup at the British Museum was most probably a ceremonial vessel. It depicts King Lycurgus of Thrace ensnared in grapevines, supposedly for offending the Greek god of wine Dionysus.
The cup was designed as a “cage-cup” made by taking a thick glass receptacle and cutting or grinding away the surface until an image emerges. Some portions are so deeply carved as to be connected only by “bridges” to the vessel itself. But it is the type of glass used that is so remarkable. Dichroic glass dramatically changes color when light streams through it. The green opaque Lycurgus Cup turns a radiantly translucent deep red when lit from behind. This is due to the Roman fabricators embedding particles of silver and gold as small as 50 nanometers in diameter, or less than one-thousandth the size of a grain of table salt—a process that was “an amazing feat” according to archaeologist Ian Freestone of University College London, one of the researchers who conducted a 1990 examination of the cup and its properties.
Interestingly, no one is sure why the Lycurgus Cup’s was created to alter its hue when illuminated. Was it a ritualistic practice? Was it a way to detect poison for a ruler? Was it for the sheer beauty of displaying light and color?
To Gang Logan Liu, an engineer at the University of Illinois at Urbana-Champaign, there’s a reason for studying this artifact and its technology. He has been focusing on using nanotechnology to diagnosis and treat disease. “The Romans knew how to make and use nanoparticles for beautiful art,” Liu says. “We wanted to see if this could have scientific applications.” Liu postulated that when a treated vessel was filled with various liquids, the vibrating electrons would change the color of the glass accordingly. The experiment couldn’t use the Lycurgus Cup for fear of damage. Instead the scientists
“…imprinted billions of tiny wells onto a plastic plate about the size of a postage stamp and sprayed the wells with gold or silver nanoparticles, essentially creating an array with billions of ultra-miniature Lycurgus Cups. When water, oil, sugar solutions and salt solutions were poured into the wells, they displayed a range of easy-to-distinguish colors—light green for water and red for oil, for example. The prototype was 100 times more sensitive to altered levels of salt in solution than current commercial sensors using similar techniques.”
So a technology developed 1,600 years ago has application potential today. Which leads to the question of what exactly is nanotechnology? Is this freaky science? A game changer for atomic engineering? Or both?
Nanotechnology is basically manipulating structures and processes at an atomic level—a world so small that it defies logic and imagination for the non-scientist. Nanotechnology originates from the Greek word meaning “dwarf”. What scale are we talking about? “A nanometre is one billionth (10-9) of a metre, which is tiny, only the length of ten hydrogen atoms, or about one hundred thousandth of the width of a hair.”
Nanotechnology has been developing over the last 20 years. The research is now leading to serious efforts in devising applications for its ongoing use. Nanobots hold the possibility of identifying and destroying cancer cells. Advances in surgical devices, diagnostic techniques and drug delivery promise to revolutionize medicine. Antiterrorism programs see nanotechnology potential in being able to quickly determine the composition of unknown liquids, chemicals and compounds to prevent attacks. The food industry is investigating nanoparticles in extending shelf life, isolating dangerous bacteria and enhancing health benefits. And for our ever-expanding world of electronics, nanopatterning is creating faster, crisper, smaller, larger, ever more eye-popping, jaw-dropping gadgets, phones and computers.
So let us pay homage to those Roman innovators of 1,600 years ago. There’s no telling how far—or how small—their ingenuity will lead us.
Want more examples of how clever our ancestors were when it comes to nanotechnology? See the nanotechnology timeline here.
For a view of the changing color of the Lycurgus cup, click here