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Abstract: Sets of 20 soda ash glasses, 16 soda lime glasses and 23 wood ash glasses mainly from excavations in Europe (additional soda ash glasses from Egypt) were analysed on 61 chemical elements. Average SiO2 is about 62% in soda glasses and 50% in wood ash glasses. The three groups of glasses contain on average 13% Na2O, 18% Na2O and 13% K2O as fluxes to lower the melting temperature of quartz at their production. The starting materials beside quartz were halophytic plant ash for soda ash glass, trona (Na3H(CO3)2·2H2O) and lime (clamshells) for soda lime glass and beech ash for wood ash glass. Each of the three major glass types contains specific Rare Earth Element (REE) concentrations mainly contained in quartz and its intergrown minerals. 50 Paleozoic and Mesozoic sandstones from Central Europe represent the quartz composition. The REE pattern of these glasses apparently indicates major compositional stages of the Continental Earth''s Crust. The boron to lithium and sodium to potassium ratios as in seawater suggest reactions of materials for soda glass with seawater. Negative Ce anomalies in the three glasses are caused by reactions of quartz with seawater. [Copyright &y& Elsevier]

Sets of 20 soda ash, 16 soda lime and 23 wood ash glasses mainly from excavations in Europe were analysed by microprobe and LA-ICP-MS for 61 elements and are presented as average concentrations with standard deviations. Concentrations of sodium, potassium and magnesium allow the major glass type to be identified. Specific compositions of the raw materials of glass production indicate certain sources, technical processes and ages. Heavy minerals etc. of quartz sands contain rare earth elements (REE) from crustal fractionations that are different for the three major glass types. Accumulations of P, B, Ba, Mn and K in wood from soils by organic processes can characterize glass from certain regions. [ABSTRACT FROM AUTHOR]