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.
Venetian glass
"Cristallo" is a soda glass, created during the 15th century by Murano's Angelo Barovier. The oldest reference to "cristallo" is dated May 24, 1453. At the time, "cristallo" was considered Europe's clearest glass, and is one of the main reasons Murano became "the most important glass center". It looked like quartz, which was said to have magical qualities and often used in religious objects. "Cristallo" became very popular. This type of glass was fragile and difficult to cut, but it could be enameled and engraved. Manganese was a key ingredient in the secret formula used to make "cristallo". An easy modification to "cristallo" made in Murano was to produce a frosted or crackle version.