This glass chalice, the Lycurgus Cup, appears jade green when lit from the front but blood red when lit from behind. The colour change is a result of the Roman artists impregnating the glass with nanoparticles of silver and gold.
This glass chalice, the Lycurgus Cup, appears jade green when lit from the front but blood red when lit from behind. The colour change is a result of the Roman artists impregnating the glass with nanoparticles of silver and gold.