The surface of this sixth or seventh-century light green bowl is covered with a pale brown coating, the result of heavy weathering. It is decorated with six rows of round facets, and was probably first blown and then cut with the wheel. Faceting was a popular decorative feature of glasses manufactured in Persia and Mesopotamia under the Sasanian kingdom (224–651), inherited from the Roman glass industry established in the Eastern Mediterranean from the first century BC to the fourth century AD. Cut transparent glasses were made to imitate carved rock crystal, a rare and much sought after hardstone. The facets were intended to produce the effect of a honeycomb pattern, creating contrasts of light and shadow.
Glass
The British Museum, WAA 1911.04-04.13