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Articles

• Abd-Alla, Ramadan

This paper focuses on the devitrification behaviour and recrystalhzation mechanism ofarchaeological glass. It also aims to reveal the fact concerning this phenomenon as adeterioration process associated with glass corrosion. Many archaeological glasses attributedand dated to the early Islamic period in Egypt were collected and analyzed using XRDspectroscopy technique to identify the mineralogical composition and determine thecrystalline phases present. A preliminary study by analytical scanning electron microscopy(SEM&EDX) allowed characterization of the elemental chemical composition of theunderlying glasses and the neocrystallisation developed on their surfaces. Furthermore, thecompositional phases and glass texture were also examined. According to the confirmedresults obtained for four glasses, it can be concluded that the archaeological glass can bedevitrified or partially recrystallize due to the corrosion process addition to the thermaleffects. Many separated crystalline phases such as quartz, calcite, tosudite, jacopsite andcalcium silicate were detected in the glass samples. This phenomenon considered one of themost dangerous deterioration aspects of corroded glass. So understanding it will assists theglass conservators in treating such corroded glass.

• History and Archaeology

• Αρχαιολογία

Glassy state, Recrystalhzation, Decomposition, Crystalline phases, Glass corrosion