History of glass
The history of glass-making dates back to at least 3600 years ago in Mesopotamia. However, they may have been producing second-rate copies of glass objects from Egypt, where this complex craft originated. Other archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or Egypt. The earliest known glass objects, of the mid second millennium BC, were beads, perhaps initially created as the accidental by-products of metal-working (slags) or during the production of faience, a pre-glass vitreous material made by a process similar to glazing. Glass products remained a luxury until the disasters that overtook the late Bronze Age civilizations seemingly brought glass-making to a halt.
Byzantine glass
A major innovation of the Byzantine period was the invention of the glass lamp. Glass lamps are first attested in the first half of the fourth century CE in Palestine, where they began to replace the clay lamps in use at the time as they were much more efficient. By the middle of the fifth century their use was rapidly spreading westward. Initially these lamps were shaped just like drinking vessels, though the number of shapes expanded to seventeen over the course of the sixth and seventh centuries.