There is a wealth of theory in countless publications regarding the dichroic nature of the glass used in the famous 4th century Roman Lycurgus Cup. However, hands-on practical analytical research on this very special object has not been undertaken for nearly 35 years. Since that time there have been substantial developments and improvements in all Analytical Scientific instruments and many new ways for data collection have become available.

Transmission Electron Microscopes (TEM) are now able to scan/raster very small electron beams to produce images and other analytical data streams at up to atomic resolution.

Specimen preparation for TEM has also advanced enormously, such that ideally electron transparent thin specimens, typically of around 100 nm thickness, can be made from precisely targeted areas in bulk samples – the Focused Ion Beam (FIB) instrument.

3D imaging using X-Ray beams can produce density images to reveal internal structural details (the Micro-CT instrument).

Optical Spectroscopy can be used to verify theoretical calculations now commonly used in Plasmonic science (UV VIS Spectroscopy).

Data collected on rediscovered samples of the Lycurgus Cup gives a new insight into the dichroic nature of the glass and demonstrates very clearly the remarkable work done 1,600 years ago by the Roman glass makers.

This talk will show new unpublished data and explain how the dichroism works.