For how much could I sell a modern glass cup in ancient Rome?

When assured the merchant was the only one who knew the secret the emperor had the inventor killed to prevent the economic dislocation such an invention would cause the current glass merchants and manufacturers. read more

One category of cut and blown glass — cameo glass — remained a luxury item, however. A bubble of hot glass of one color was encased in a layer of one or more colors, and after annealing (slow cooling), the outer layers were cut away to create a design in relief. read more

Analysis of Roman glass has shown that soda (sodium carbonate) was used exclusively in glass production. During this period, the primary source of soda was natron, a naturally occurring salt found in dry lake beds. read more