Glass served the Romans for personal ornaments and for architectural decorations, sometimes even for windows. They made beautiful artificial gems of colored glass; they decorated glass with gold leaf. When the barbarians overthrew the Western Roman Empire, the art of glassmaking came to an abrupt halt in Europe. It continued to flourish, however, in the East, particularly in the Byzantine Empire.
Glassmaking was revived in Western Europe toward the end of the eleventh century. The Italian city state of Venice became especially noted for its fine colored glass with decorations in enamel and gold tracery and for exquisite filigree patterns, like lace made of glass threads.
By the time Venice had produced these masterpieces, all the fundamental glass-forming processes were known. Until the late 1700's, advances in the glass industry were limited to the discovery of a few new raw materials and to the development of artisans' skills. Then machinery was introduced and came to be widely adopted.
Today, the industry is almost completely mechanized, though hand operarations are still used in some small-volume specialized fields. There has been a remark advance in glass technology, particularly providing new ingredients and in modifying the heating treatment so as to bring about a variety of desired properties.
