Sassanid glass

Before the arrival of Islam in the seventh century, Iran was ruled by the Sassanids (224-651 A.D.). In their palaces, the Sassanid kings surrounded themselves with excessive luxury. Their formidable glass art is a good example of this.
The Sassanid glassmakers were especially adept at cutting glass in complex patterns. To produce these, they cut the thick walls of bowls and jugs into facets. This resulted in products that formed technical and aesthetical tours de force, finding their way even into 6th-century Japan.
It would seem that the characteristic Persian facetted glasswork was created for economic reasons: glass had to compete with the much more costly dishes and bottles made of rock crystal.