There is still some doubt as to when and where glass was invented. The tradition passed on by Pliny locates the event on the Phoenician coast, in modem Lebanon, where there later grew one of the most important glass-making centers. In Egypt, the first glass we know of, as a component of faience ware, dates from as far back as the Neolithic Badarian culture at the turn of the 5th and 4th millennia BC. Glass is produced from a mixture of silica-sand, lime and soda, colored with the copper ore malachite and fused at a high temperature. In the oldest Egyptian faience ware a skin of this substance was applied to a core made of silica-sand and clay, or of the stone steatite. This was used at first only for beads, but later on for amulets, shawabtis (the little figurines of the attendants of the deceased), other figures and inlays (shapes inserted into the sides of vessels, wooden objects, or into plaster). Particularly in the Middle and New Kingdoms a faience glaze was often applied to complete vessels and statuettes.
Pure glass as a separate material came later, in predynastic times, in the form of translucent beads. In the Old and Middle Kingdoms glass jewelry, amulets, little animal figures, mosaic stones and similar things made their appearance.
Not till the reign of Tuthmosis I in the New Kingdom, however, is there any record of glass vessels being made. The innovation was probably due to Egyptian expansion in the Middle East. There Egyptian soldiers and administrators would have come across advanced centers ofglass manufacture and brought back local craftsmen, probably as slaves. This view is reinforced by the fact that production of glass vessels started in Egypt as a royal monopoly serving the court, top dignitaries and the high priesthood. Such 18th-dynasty workshops as have been discovered were very close to royal palaces, such as that of Amenophis III at Malqata or Akhenaten's residential quarter in Akhetaten. Further 19th-dynasty factories have been found at Lisht, Menshiya and possibly Gurob. Unlike those of other crafts, portrayals of glass production are conspicuously missing from drawings and reliefs. (Alleged illustrations of glass-making that have been reproduced from time to time are in fact metal foundries.) This was no doubt because of the royal monopoly. Since the aristocracy owned no glass workshops, the subject did not feature in their tombs, and in New Kingdom royal tombs non-religious scenes were very rare. The methods of glass manufacture would thus have remained a mystery but for archaeological research and the extant glass vessels themselves.
Not till the reign of Tuthmosis I in the New Kingdom, however, is there any record of glass vessels being made. The innovation was probably due to Egyptian expansion in the Middle East. There Egyptian soldiers and administrators would have come across advanced centers ofglass manufacture and brought back local craftsmen, probably as slaves. This view is reinforced by the fact that production of glass vessels started in Egypt as a royal monopoly serving the court, top dignitaries and the high priesthood. Such 18th-dynasty workshops as have been discovered were very close to royal palaces, such as that of Amenophis III at Malqata or Akhenaten's residential quarter in Akhetaten. Further 19th-dynasty factories have been found at Lisht, Menshiya and possibly Gurob. Unlike those of other crafts, portrayals of glass production are conspicuously missing from drawings and reliefs. (Alleged illustrations of glass-making that have been reproduced from time to time are in fact metal foundries.) This was no doubt because of the royal monopoly. Since the aristocracy owned no glass workshops, the subject did not feature in their tombs, and in New Kingdom royal tombs non-religious scenes were very rare. The methods of glass manufacture would thus have remained a mystery but for archaeological research and the extant glass vessels themselves.
The glass factory found at Lisht yielded fragments of crucibles, conical clay stands for holding the crucibles during fusing, pieces of slag from the ovens, samples of the pigments added to the glass, little discs with well-worn edges used for finishing the surfaces, over too glass rods of various colors, pieces of unfinished faience ware and nearly 200 sherds of glass vessels. There are traces on the inside of some vessels of a clay-and-sand core, revealing the technology used.
Manufacture proceeded as follows. The raw glass was heated in pans up to 750'C and then again in crucibles to as high as 1000C. A clay-and-sand core was made in the shape of the cavity of the intended vessel, covered with cloth and stuck onto a metal rod. This was plunged into the molten mass and given several quick twists to spread the glass evenly over it. (This did not always work out, as we can see from the uneven thickness of some vessels.) If decoration was required, one or more thin colored rods were wound spirally over the glass while it was still soft. Before these rods hardened they were moved up and down with metal pins to produce waves, garlands, arches and leaf or feather patterns. Sometimes a comb was drawn across the rods, producing a series of vertical ribs. The whole job was then reheated and rolled over a smooth stone block to produce an even surface. Finally, edge and foot could be pulled out and handles fused on. Once the object was cold, the core had to be scraped out. Ancient Egyptian glass was usually tinted with pigments added to the raw glass. A milky-white color was produced with tin or lead oxide, yellow with antimony and lead, or ferrous compounds, red or orange with oxides of copper, violet with manganese salts, greenish blue (in imitation of the prized turquoise) with copper or iron compounds, dark blue (in imitation of lapis lazuli) with cobalt com-pounds and black with a larger proportion of copper and manganese, or with ferric compounds. The finished artifacts - little bottles, vases, goblets and bowls - were chiefly destined to hold cosmetics and fragrant unguents in the boudoirs of queens and high-born ladies. The decline of royal power after the end of the New Kingdom put a stop to glass production for a time. Not till the Graeco-Roman Period did new Egyptian glass centers arise in the Hellenistic cities of Alexandria and Naucratis. These enjoyed close links with centers in Asia Minor and their extant Greek-style products show that they followed the international market of their day. Around the beginning of the Christian era molded glass bowls appear, and another innovation was millefiori glass made from variously colored glass rods fused together. The revolutionary invention of glass-blowing took place, probably in Syria, during the 1st century BC, though the technique did not reach Alexandria until the latter half of the following century. As a rule clear glass was used, either of the natural greenish hue or with additives to make it colorless. It was cut with a copper wheel and ground with emery powder. The new discovery increased production many-fold and glass then ceased to be either a rarity or an upper-class prerogative.
What the social status of glass-makers may have been we can only speculate. It was a highly artistic craft and gifted individuals had a chance to become acknowledged masters. Though the glass-factory employees appear originally to have been slaves, and for the most part foreigners, skilful workers were probably freed at an early stage and imparted their secrets to Egyptian colleagues among the royal artisans. The work was doubtless strenuous and damaging to the health of its practitioners. The intense heat produced by fusing glass on open fires could injure the body-fluid management; the cornea and retina of the eye suffered from the glare, and skin burns were no rarity. Glass-blowing exerted a back-pressure on the lungs that could lead to emphysema and circulatory trouble at an early age, shortening a worker's life considerably.
Manufacture proceeded as follows. The raw glass was heated in pans up to 750'C and then again in crucibles to as high as 1000C. A clay-and-sand core was made in the shape of the cavity of the intended vessel, covered with cloth and stuck onto a metal rod. This was plunged into the molten mass and given several quick twists to spread the glass evenly over it. (This did not always work out, as we can see from the uneven thickness of some vessels.) If decoration was required, one or more thin colored rods were wound spirally over the glass while it was still soft. Before these rods hardened they were moved up and down with metal pins to produce waves, garlands, arches and leaf or feather patterns. Sometimes a comb was drawn across the rods, producing a series of vertical ribs. The whole job was then reheated and rolled over a smooth stone block to produce an even surface. Finally, edge and foot could be pulled out and handles fused on. Once the object was cold, the core had to be scraped out. Ancient Egyptian glass was usually tinted with pigments added to the raw glass. A milky-white color was produced with tin or lead oxide, yellow with antimony and lead, or ferrous compounds, red or orange with oxides of copper, violet with manganese salts, greenish blue (in imitation of the prized turquoise) with copper or iron compounds, dark blue (in imitation of lapis lazuli) with cobalt com-pounds and black with a larger proportion of copper and manganese, or with ferric compounds. The finished artifacts - little bottles, vases, goblets and bowls - were chiefly destined to hold cosmetics and fragrant unguents in the boudoirs of queens and high-born ladies. The decline of royal power after the end of the New Kingdom put a stop to glass production for a time. Not till the Graeco-Roman Period did new Egyptian glass centers arise in the Hellenistic cities of Alexandria and Naucratis. These enjoyed close links with centers in Asia Minor and their extant Greek-style products show that they followed the international market of their day. Around the beginning of the Christian era molded glass bowls appear, and another innovation was millefiori glass made from variously colored glass rods fused together. The revolutionary invention of glass-blowing took place, probably in Syria, during the 1st century BC, though the technique did not reach Alexandria until the latter half of the following century. As a rule clear glass was used, either of the natural greenish hue or with additives to make it colorless. It was cut with a copper wheel and ground with emery powder. The new discovery increased production many-fold and glass then ceased to be either a rarity or an upper-class prerogative.
What the social status of glass-makers may have been we can only speculate. It was a highly artistic craft and gifted individuals had a chance to become acknowledged masters. Though the glass-factory employees appear originally to have been slaves, and for the most part foreigners, skilful workers were probably freed at an early stage and imparted their secrets to Egyptian colleagues among the royal artisans. The work was doubtless strenuous and damaging to the health of its practitioners. The intense heat produced by fusing glass on open fires could injure the body-fluid management; the cornea and retina of the eye suffered from the glare, and skin burns were no rarity. Glass-blowing exerted a back-pressure on the lungs that could lead to emphysema and circulatory trouble at an early age, shortening a worker's life considerably.
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