Catalogue Entry听
From the Catalogue of听Ancient Glass in the University of Colorado Museum
Gift of H. Medill Sarkisian and Justine Sarkisian Rodriguez (1979)
听(2008)
Height:听4.8 cm
Diameter (max.): 17.8 cm
Roman, 1st century C.E.
Classification: Isings Form 3c;听Harden Fabric 1
Description: Slightly outcurved rim on a wide bowl. 65 relatively evenly spaced ribs around center of bowl, reaching neither the lip nor the base. Colorless, almost听transparent glass with green tint.听Chip missing from rim.听 and a large rusty patch extending in an arc from the rim to the bottom.听Sagged.
Comment: Not enough examples of this type come from an archaeological context to establish a definite chronology; a handful of fragments from the western provinces of the Roman Empire belong to the 1st century C.E.听Other similar examples are Eisen 1927, pl. 40;听Hayes 1975,听no. 47;听Fitzwilliam Museum 1978,听no. 32c;听Constable-Maxwell Collection 1979,听lot 38;听and Grose 1989,听no. 234.
The shape of the rust damage indicates either a repair of a large break听or that at one time the bowl was on display on a bad metal mounting, presumably propped up like a modern decorative plate.
Discussion
This bowl was not听blown听or听core-formed听when shaped. Instead, it was formed by a process called "sagging"听or "slumping."听This involved a sheet of glass being heated until pliable, then placed over a dome-shaped mold, so that the edges would sag and slump down. The shape of the bowl was made while it sat upside-down. The edges were polished and flattened after the sagging was complete (1). Ribs like the ones seen on this bowl were slapped or carved into the glass (while still upside down) when the glass was still soft enough to be worked (2).
Romans valued colorless, clear glass more than colored and opaque glass. Colorless bowls and vases were significantly more expensive than their colorful counterparts. Manufacturing glass that did not have a lot of pigment required an extra ingredient. This ingredient was a neutralizing agent that would prevent the metals in the sand from tinting the glass (3). During 听(69-86 C.E.) Romans became obsessed听with colorless glass objects, due to the popularity of cut rock crystal vessels. Clear, untinted glass resembled the very expensive crystal听and therefore provided a cheaper alternative (4).
Footnotes
- Robert J. Charleston,听Masterpieces of Glass: A World History from the Corning Museum of Glass听(New York: Harry N. Abrams, Inc., 1980): 39-40.
- Donald B. Harden,听Roman Glass from Karanis听(Ann Arbor: University of Michigan Press, 1936): 19-20.
- Harden 1936: 6-9.
- E. Marianne Stern,听Roman, Byzantine, and Early Medieval Glass听(New York: Hatje Cantz Publishers, 2001): 130-131.
References
- Catalogue of the Constable-Maxwell Collection of Ancient Glass.听London: Maggs Brothers,听1979.
- Eisen, G. A.听Glass: Its Origin, History, Chronology, Technic and Classification to the Sixteenth Century, v. 1.听New York: W. E. Rudge,听1927.
- Glass at the Fitzwilliam Museum.听Cambridge: Cambridge University Press,听1978.
- Grose, D. F.听Early Ancient Glass: Core-Formed, Rod-Formed, and Cast Vessels and Objects from the Late Bronze Age to the Early Roman Empire, 1600 B.C. to A.D. 50.听New York: Hudson Hills Press, 1989.
- Hayes, J. W.听Roman and Pre-Roman Glass in the Royal Ontario Museum.听罢辞谤辞苍迟辞:听1975.