Replicating The Color-Changing Effect Of The Lycurgus Cup

Although most archaeological finds from ancient civilizations aren’t quite as exciting as what you might expect from the movies, occasionally you come across something that’s truly special. The Lycurgus Cup is one of those, with the 3rd or 4th century CE glass cup and its incredible detail surviving likely because it ended up in church treasuries after the fall of the Western Roman Empire. Now its almost magical dichroic glass effect has been recreated in a modern take by researchers at the University of Sheffield.

The Lycurgus cup with light shining through it. (Credit: Chappsnet, Wikimedia)
The Lycurgus cup with light shining through it. (Credit: Chappsnet, Wikimedia)

Dichroic glass takes on a different color depending on the lighting conditions, with the Lycurgus cup appearing to be green glass when lit from the front and red when light passes through it from behind. This serves to give the portrayed scene – of the demise of King Lycurgus from Greek mythology – an extra boost with the right lighting.

The cause of this dichroic effect in this ancient marvel of glass work was unknown for the longest time, but research on a fragment of the glass revealed that it contains nanoparticles of both gold and silver. Since then a number of researchers have recreated this dichroic glass, with [Lars Kool] et al. using FDM 3D printing to create objects embedded with the same nanoparticles that also display this effect.

Where this work by the University of Sheffield differs is in that it creates the effect not only in glass, but also creating a piece of art in the form of a modified Atlas statue to use it. The resulting dichroic effect is rather similar, which isn’t too shocking since unlike over 1,600 years ago we can now literally see and measure nanoparticles in glass, while adding exact amounts of each to pure glass.

Here’s to raising a dichroic glass cup to bridging the millennia with recreated luxury glass recipes.

Trailblazing Artisans Of Road Building

A lot of us take roads for granted, at least until they are icy or torn up by construction. The concept of creating fixed paths seems to be in our firmware. Finding the shortest distance to food or water and marking a trail to it from home base has always been its own reward.

Roads have come a long way from the simple paths beaten by man and beast. But the basic configuration of paved roads hasn’t changed all that much since the Roman empire. Whatever they’re made of, they need to be able to drain water and support heavy loads.

New issues arose as modes of transportation shifted in favor of the automobile. Road surfaces needed to provide friction against tires. But how did we get from the stone-paved roads of Rome to the asphalt and concrete roads of today?

Continue reading “Trailblazing Artisans Of Road Building” →