The glass of the Coptic period—third to twelfth centuries—was the heir to a long tradition of glassmaking in Egypt. While Coptic glass exhibited some regional variations, it did not differ substantially from glass in neighboring areas.
Glass was manufactured in Egypt from about 1500 B.C.; it reached its acme of beauty in the luxury glassware made at Alexandria in the Ptolemaic and early Roman periods (300 B.C.- A.D. 100). Sand, soda, and lime, the ingredients of glass, were readily available in the deserts of Egypt. These components were heated over wood fires until they were molten and were worked while viscous. Early glass, laboriously made, was rare and expensive. By the first century B.C., however, glassworkers had discovered the technique of picking up a blob of molten glass on the end of a hollow tube and blowing air into it. This glassblowing technique revolutionized glassmaking, since glass vessels could be manufactured much more speedily and therefore became a common and inexpensive item. Although this change came slowly to Egypt, by the Coptic period glass was found in abundance.
The glass furnaces of this era have not been found; nevertheless, the quantity and simplicity of most glass used in Egypt suggest that a number of small factories produced glass articles for local use. Evidence from other areas around the Mediterranean shows that glass factories could be quite small and simple. For example, the scanty remains of a third-century glass furnace at present-day Salona, Yugoslavia, comprise a rectangular melting tank about 2.5 by 5 feet (0.80 by 1.50 m) within a small furnace structure. Glassmaking installations in Galilee also used built-in rectangular melting tanks, while in other areas separate clay pots have been found.
Since early glass furnaces do not survive above the foundation level, we must depend on descriptions and illustrations in medieval manuscripts for the appearance of complete furnaces. Those of the southern and eastern Mediterranean seem usually to have been circular structures with the fire at the lowest level, the melting pots and work area at the middle level, and the annealing space for gradual cooling of the finished glass at the top.
Ordinary ancient blown glass was blue-green, yellow-green, pale blue, or amber in color. Added decorative elements were often in darker blue or green. These colors were easily obtainable from the batch materials. Impurities in glass sand, for example, imparted the characteristic greenish tone to ancient glass. Truly colorless glass, achieved by the addition of manganese or antimony, was rarer and more expensive.
The blowing process imparted both thinness and translucency to glass, qualities that made it usable not only for vessels but also for windows, jewelry, and lamps. To make a vessel, the glassblower would pick up a gather of molten glass on the blowpipe and shape it with simple metal and wood tools while constantly reheating it to working temperature. A second, solid metal pipe, the pontil rod, was attached to the base of the vessel, and the rim of the vessel was knocked off the blowpipe when handles and decoration were completed.
Decorative effects were achieved by adding trails or blobs of hot glass, by pinching and pulling the vessel to form indentations or ribs, by blowing the glass into a mold, and by engraving. Glass was often blown into a mold to impart, for example, a ribbed design, then withdrawn and further inflated, softening and sometimes twisting the original pattern. Glass decorated with cut facets or engraved with elaborate figural and floral motifs was a specialty of the early Roman glassmakers of Alexandria. This tradition continued in somewhat diminished form for several centuries. Horizontal wheel-cut lines and facet cutting decorated beakers and bowls, while geometric patterns of a shallower cut ornamented jugs and bottles.
By the ninth century, after the Islamic conquest, new uses, shapes, and decorative techniques changed Egyptian glass into something distinctively different from earlier work. Techniques such as painting in luster (metallic glaze) were used at first for Coptic motifs and subsequently for the Islamic repertoire. Pincered designs were applied to small vessels with patterned tongs, and white marvered-in threads decorated glassware of purple, red, and gray. In the ninth and tenth centuries, glass was deeply cut from blanks in imitation of rock crystal. New uses for glass included coin weights and medical utensils such as cupping glasses.
The most important archaeological evidence of Coptic glass comes from the Greco-Roman town of Karanis in the Fayyum, excavated from 1924 to 1935 by the University of Michigan; information on the glass was published by D. B. Harden. Listed but not fully presented is the glass from the 1905-1909 excavations of the Monastery of DAYR APA JEREMIAH at Saqqara. Between them these sites span the periods of the second through fifth centuries and the sixth through mid-ninth centuries. More recent excavations at Cairo continue the history of glassmaking after the Islamic conquest. Apart from these sites, the evidence consists of scattered references to finds, museum glass with probable Egyptian provenance, and brief mentions of glass and glassmakers in papyri and manuscripts.
Tableware and Storage Vessels
Karanis provides the best evidence for the types of domestic table glass used in Roman and Coptic Egypt; similar examples come from other sites. Among the most common shapes in use were plain, blown, shallow and deep bowls on high foot rings, made in a wide range of sizes. The bowls were often oval, a characteristic of Egyptian glass not found elsewhere in plain blown glass. Another distinguishing feature of bowls and other footed shapes is the clearly visible crisscross marks of the tool used to pull out and shape the base rings.
The common form of late antique drinking vessels in Egypt, as elsewhere in the Mediterranean, was a deep-bowled goblet on a stem, similar to the modern wine glass. The Egyptian version was distinguished by the thin walls of the bowl and the foot-shaping technique mentioned above. Storage vessels included tall cylindrical bottles, generally dark olive-green, sometimes decorated with shallowly engraved geometric patterns—ovals, diamonds, and lines. Handleless flasks were also in use, a typical form having a globular body, long narrow neck with constriction at the base, and flaring folded rim. This shape was often decorated with an added crimped collar of darker glass. The bodies were sometimes shaped in a mold to produce a swirling ribbed pattern. Small jars were often decorated with à jour (open-work) threads trailed from rim to shoulder and with vertical trails below the side handles. Although these features are also seen on eastern Mediterranean glass, Egyptian examples were distinguished by their thin fabric and crimped base rings. As at other sites, large numbers of unguentaria (perfume bottles) were found. The earliest shapes are similar to long-necked types in both East and West. The small, squat bottles most common at Karanis, are, however, quite different from those made elsewhere.
Some finer glass, probably made at Alexandria, was found at Karanis and at other Egyptian sites and was widely exported as well. From the second and earlier third centuries come small rounded bowls of colorless glass, engraved either with mythological designs and Greek inscriptions or with overall facet-cut patterns. Two facet- cut beakers from an even earlier period were carefully preserved as heirlooms in a Karanis household. Facet-cut “dolphin bottles” with globular bodies and two small handles were made in the third century, while in the fourth century tall cylindrical bottles were decorated with shallowly scratched facets, diamonds, and other patterns. The relatively rare appearance of such glass on Egyptian sites suggests that they were an expensive item destined more for the export trade than for common domestic use.
Groups of glass vessels stored in the Karanis houses suggest how glassware was used in the average household. In one instance a group of six oval dishes and six shallow bowls found together with other shapes indicates a complete glass table service. More frequently one or two examples of each shape were found along with glass lamps (discussed later) and small flasks. That this plainer blown glass was considered the finer tableware is suggested by its storage along with pieces of imported redware pottery.
The glassware found at the Saqqara monastery corresponds to glass of early Islamic type from elsewhere in Egypt. Prominent are small bowls with raised designs applied with patterned tongs to the hot glass. Flasks have globular bodies and tall, very narrow necks, while other glasses exhibit the characteristic Islamic decoration of marvered-in white threads in a brilliantly colored matrix. There are also glass coin weights stamped with dates ranging from the early eighth to the mid-ninth century.
The recent excavations at al-Fustat revealed similar types of glass in such quantity as to indicate local manufacture there. Given the proximity of Saqqara to al-Fustat, it seems likely that the monastery obtained its glassware from this nearby source, since the highly skilled glassmaking craft was not carried on in the monasteries themselves.
From the fourth century on, lamps of glass were in wide use. The earliest type in Egypt, as elsewhere, is a long, conical shape with a knocked-off or fire-polished rim, pointed or knob base, and decoration of horizontal wheel-cut lines, zigzag threads, or applied blue glass blobs. At Karanis small versions about 4 to 5 inches (10-13 cm) in height were in use, probably supported in low wooden tripod stands. Larger examples, about 8 inches (20 cm) and over in height, were generally suspended from the ceiling in groups by means of metal holders. These holders consisted of metal disks with multiple openings for the insertion of several lamps. They were hung horizontally and suspended from chains. Descriptions of early churches include mention of such chandeliers. The shapes of the glass lamps evolved through time. Some were deep bowls with three handles, used free-standing or hung, while the type most often hung in chandeliers had a wide bowl and heavy stem.
Windows and Wall Decoration
Glass in windows in Egypt is not definitely attested before the sixth century. From this time it has been found in the Saint Jeremiah Monastery at Saqqara in the form of small panes of circular crown glass, colorless, purple, or blue, cut into small pieces and fastened with clay into circular- or rectangular-patterned limestone window frames.
Also at the Saqqara monastery, mosaic glass cubes were found fallen from the vaulted dome of the church. Among the variegated opaque and translucent colors, the most important were clear glass cubes encasing gold leaf, the same technique used in the Christian gold glassware of the catacombs.
Glass wall decoration is seen from an earlier period in two fragmentary Coptic-style figures found at Antinoë (ANTINOOPOLIS). These were made of glass intarsia, that is, large, shaped pieces of glass glued to a backing. Outside of Egypt, at Kenchreai in Greece, many large glass wall panels in this technique have been found; these were undoubtedly imported from Egypt. A fragmentary glass intarsia picture of Saint Thomas with a cross uses this technique for a Christian subject.
Luster Painting on Glass
The decorative technique of luster painting on glass seems to have begun in pre-Islamic Coptic Egypt and was later adapted to Islamic taste with new motifs. In luster painting, metal salts of silver and copper were painted onto the glass and kiln-fired at low temperatures to produce translucent colored designs. Eventually this Egyptian glassmaking technique was adapted for luster painting on pottery. The crucial evidence comes primarily from glass fragments, notably from Saqqara. An important fragment shows the head and arm of a saint holding a cross with the inscription “agios” to one side. This must have been one of a procession of saints such as are found so often in Coptic painting. A complete beaker in the Victoria and Albert Museum, London, represents in luster the tree of life growing from an urn, a frequent textile motif. Further fragments with Coptic figural and floral designs in the Benaki Museum, Athens, the Louvre Museum, Paris, and elsewhere suggest that this technique was known to glassmakers in Egypt as early as the sixth century or, as the glass scholar C. J. Lamm surmised, even earlier.
Religious Uses of Glass
The small pendant crosses worn by the Christians of Egypt often had colored glass inlays, a religious adaptation of the widespread use of glass in secular jewelry.
The Coptic Acta martyrum, written about A.D. 300, records testimony from one Apa EPIMA, who when ordered by the magistrates at al-Bahnasa to bring in his presbyters, deacons, and altar vessels replied that “our communion vessels are of glass, for we are poor men who live in a small village.” These vessels probably resembled contemporary glass tableware or imitated the silver vessels used in wealthier congregations. The colored glass windows, glass lamps, and glass mosaics that lit the dim interiors of the churches undoubtedly enhanced the religious experiences of these early Christian worshipers.
- Charleston, R. J. “Glass Furnaces Through the Ages.” Journal of Glass Studies 20 (1978):9-33.
- Clairmont, C. W. Benaki Museum: Catalogue of Ancient and Islamic Glass. Athens, 1977.
- Harden, D. B. “Roman Glass from Karanis.” University of Michigan Studies, Humanistic Series, Vol. 42. Ann Arbor, Mich., 1936.
- . “Ancient Glass, I: Pre-Roman”; “Ancient Glass, II: Roman”; “Ancient Glass, III: Post-Roman.” The Archaeological Journal 125 (1968):46-72; 126 (1969):44-77; 128 (1971):78-117.
- Klein, D., and W. Lloyd, eds. The History of Glass. illus. pp. 13, 32. London, 1984.
- Lamm, C. J. Oriental Glass of Mediaeval Date Found in Sweden and the Early History of Lustre-Painting. Stockholm, 1941.
- Pinder-Wilson, R. H., and G. T. Scanlon. “Glass Finds from Fustat: 1964-71.” Journal of Glass Studies 15 (1973):12-30.
- Quibell, J. E. Excavations at Saqqara, Service des Antiquités de l’Egypte. I (1905-06), Cairo, 1907; II (1906-07), Cairo, 1907; III (1907-08), Cairo, 1909; IV (1908-09), (1909-10), Cairo, 1912.