Sculpture recreates odd optical effects of famed Lycurgus Cup

An elusive recipe

In 2020, Dutch researchers reproduced the green/red dichroic effect of the Lycurgus Cup in a 3D-printable nanocomposite material by embedding small amounts of silver and gold nanoparticles of the proper size and shapes. But nobody had yet devised a consistent, replicable recipe. University of Sheffield scientists Lisa Hollands and Caroline Jackson—the latter an expert on Roman glass—worked together to come up with one, experimenting with different furnace types, materials, oxygen levels, and at one point including sugar in the mix.

“I knew that making a glass of this type was likely to be a complex task, as it is not just a case of adding nanoparticles to glass,” said Hollands. “I’ve studied and worked with glass for over 25 years, so I used the knowledge and experience I’ve gained, coupled with a modern scientific understanding of what I was trying to achieve—although if the Romans could have seen me experimenting, they’d probably laugh and ask: ‘Why does she not know how to make this?’”

The experimentation paid off when Hollands found a mix that produced glass with the desired optical effects, appearing green in reflected light, red when backlit. Her initial glass piece was exhibited at LightFest, which is part of Molecular Photonic Breadboards, a UK project geared toward designing new materials that harness the power of light for sustainable technologies. Project leaders next decided to commission UK glass artist Elliott Walker—the S2 winner of Netflix’s Blown Away competition—to create a contemporary sculpture to pay homage to the original Lycurgus Cup.

“It is a very rare thing to have the opportunity to work with glass developed from ancient mixtures and recipes, and it is always a very exciting one,” said Walker. “You can really get an idea of how the glass makers of the past would have adapted to this sort of glass; it’s like shaking their hands. I wanted to keep the sculpture quite classical in form and to carry through the original story of Lycurgus shown on the cup, but we needed a blown element within this to really show the dichroic glass. The piece is a blend of the Lycurgus story and the Farnese Atlas sculpture, with the globe replaced by a cup.”

The public will get its chance to see Walker’s sculpture in person when it is unveiled at the Millennium Gallery next month during the University of Sheffield’s Festival of the Mind. After that, it will have a permanent home on display at the university’s Turner Museum of Glass.