Engraved Blue Glass Bowl
Found in Nishapur, Iran
(If not created locally, then most likely in Syria or Iraq)
Although the art of scratch engraving glass was known throughout the Roman empire, there are no Persian examples found until the 8th and 9th c.. These pieces with incised decoration have been found all over the Islamic world and traveled the Silk Road trade routes as far away as China (Famen Temple, sealed in 874 AD). None of the found items bear dated inscriptions, so they have been dated primarily by their position in archeological sites. The main finds have been at Susa, in south-western Iran (8th c.), Bet She’an, Israel (8th & 9th c.); Samarra (9th c.), and Fustat (9th c). Although fragments have been found in some later period sites, it is assumed that these were actually made during the 8th or 9th c. A few of these pieces were found at the Nishapur site (see images 1-3), and it is not known if they were locally produced, as some everyday glass clearly was, or, as is more likely, they were manufactured in Syria or Iraq and caught transit to eastern Asia. Interestingly, they have very similar decoration as the six plates found in the temple in China and were likely made in the same workshop.
Most commonly this type of engraving was done on a dark glass, most likely so that the lines show up well. Cobalt blue is the most prevalent of the existing artifacts. The bowl is made of Moretti glass that I formed in a clay mold (also of my making) in a firebrick kiln. The Moretti glass is a slightly softer glass that some of the other modern glasses, and is therefore closer to the period composition. Chemical analysis of the glass indicates that the Nishapur pieces were made with plant ash, not natron-which would have been more indicative of Egyptian manufacture.
Scratch engraving is created by scratching the surface of the glass with a pointed tool that is harder than the glass itself. This is also referred to as the sgraffito technique.(Stafano, Glass from Islamic Lands p72) Diamonds are frequently used, but ruby, beryl, topaz, garnet and possibly rock crystal could have been used as well. (Stafano, Glass of the Sultans, p 31) To scratch my engraving, I used a piece of metal embedded with diamond chips. In planning my design, I incorporated the common motifs of incised circles, "rope", and five leafed plants, as well as the hatched lines to fill in areas. Some existing pieces are extremely complex and ornate, while others are quite simplistic and crude. I strove to fall somewhere in the middle. It is interesting to note that there are examples of the engraving being done on either the inside or the outside of the piece…whichever was the more visible surface while in use. As I chose a shallow bowl, I decided to engrave the inside, since it is what will be seen. This did make the angle of work more difficult at times, as well as resulting in a rough food surface. In future I will probably stick with outside decoration.
Bibliography
Carboni, Stafano. Glass from Islamic Lands. New York: Thames & Hudson, 2001
Carboni, Stefano and David Whitehouse. Glass of the Sultans. New York: Metropolitan Museum of Art, 2001.
Chelkowski, Peter et.al. Mirror of the Invisible World. New York: Metropolitan Museum of Art, 1975.
Cummings, Keith, A History of Glassforming. Philadelphia:U of PA Press, 2002
KröGer, Jens. Nishapur. New York: Metropolitan Museum of Art, 1995.
Lukonin, Vladimir et.al. Lost Treasures of Persia. Washington: Mage, 1996.
McCray, Patrick. The Prehistory & History of Glassmaking Technology. American Ceramic Society, 1998
Ricke, Hemut, Glass Art: Reflections of the Centuries. Munich: Prestel Verlag, 2002.