ABSTRACT
Let us go back 1700 years or so, to the Roman Empire, inside a workshop. An artisan is molding a cup out of glass near an open žre. e cup depicts King Lycurgus being dragged into the underworld by Ambrosia. e glass mixture he is molding contains traces of metal. e artisan sets the cooling glass on his workbench and admires his handiwork. e glass is green, like jade. He liÅs a twig from the žre and puts the burning end into the cup, so that the light from the ¬ame shines through the glass. e glass turns from green to red. He grins approvingly.
