LEVANT 31 1999 Archaeological and Scientific Evidence for the Production of Early Islamic Glass in al-Raqqa, Syria Julian Henderson Department of Archaeology) University of Nottingham) University Park) Nottingham) NG72RD) U.I<:. Archaeological excavations of an Islamic industrial complex in northern Syria at al-Raqqa have revealed comprehensive evidence for Abbasid high temperature industries. Amongst the evidence is some for glass production. The evidence included a glass workshop consisting of the remains of three-chambered 'bee-hive' furnaces and a centralised flue system, the debris of casting glass into blocks of three different sizes, glass moils of two diameters (the knock-offs from blowing irons) and discarded lumps of frit, a material produced by the initial stage in glass production. In addition, fragments of a second kind of glass furnace, a tank furnace, were found. Scientific analysis of the products and by-products of this glass industry using electron probe microanalysis has produced an unexpectedly wide range of glass chemical compositions. In some instances discrete compositions are correlated to the function of the glass such as its use to make cast blocks and window panes. In others instances, such as when it is used to make glass vessels, the same apparent degree of specialisation in the deliberate selection of particular glass raw materials is not evident. Scientific analysis of frit has shown that the glass used to make the windows for glazing the al-Raqqa palace complexes was made in al-Raqqa. I Historical background 500Km """"-----'----'-----""'----', TURKEY ••••••• w ••• ••• ••••••••••••••••• IRAQ ...... • Hama ... ':.':: :;".~'" Medi~~~aneanf/ .........• Horns SYRIA ..... ,.... :;j: ~ Damascus . .f"::.') . •.•..•...••••..• ,:!.;•• (:':& \i JORDA~.::.·:.::> .............................. Figure 1. The location of al-Raqqa. The city of al-Raqqa in northern central Syria is located close to the junction of the river Euphrates and its tributary the Balikh (see Figure 1). The origin of the settlement of Raqqa was in the third century BC, when Seleucus I Nikator (301-281 BC) founded the Hellenistic city of Nikephorion, later probably enlarged by Seleucos II Kallinikos (246-226 BC) and subsequently named Kallinikos/Callinicum after him. It was destroyed by the Sasanid Khusraw I Anushirwan in AD 542, and re-built by the emperor Justinian (527-565) as part of the fortification programme of the Byzantine bor- der along the Euphrates (aI-Khalaf and Kohlmeyer 1985). The classical city was conquered in AH/ AD 18/639 or 19/640 by the Muslim army under 'Iyad b. Ghanm. It was an important centre in the Umayyad period (c. mid-eighth century) as a protective garri- son and became known as al-Raqqa. Until the twelfth century a Bishop resided· in al-Raqqa and four monasteries were attested to have been located there (Meinecke 1991; 1994; Meinecke and Heusch 1985). 225