Polish Archaeology in the Mediterranean (8.1996(1997))

formula is the relation of the sand contents to the sum of sodium
and potassium oxide contents.
The results of the analysis under a high-temperature
microscope indicate that all the samples are so called long glass in
range of hand forming. It means that they have a large range of
forming temperatures: 300°C (Tab.3, Fig. 1).
All the glass samples are long sodium-calcium-aluminium-
silica glass melted with natural soda. Trace elements, especially
cyrconium and itrium, clearly indicate a very different source of
sand used in the production of sample 1, as compared with the
other two samples. This probably means that sample 1 is of
a different provenience.
The samples are very long and also soft, meaning that they
were practical in the making with relatively low temperatures and
a broad temperature range for forming.

References:
M. Daszkiewicz, J. Raabe (1996), Chemical composition and
technological studies of Abbasid glasses from the Bijan Island in
Iraq, in: K.Bartl (ed.) Continuity and change in Northern
Mesopotamia from the Hellenistic to the Early Islamic Period,
Berlin.

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