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Title: The long-term change in composition of Medieval woodash glass


Wedepohl, Karl Hans

Date issued/created:


Resource type:



Archaeologia Polona Vol. 45 (2007)


Institute of Archaeology and Ethnology Polish Academy of Sciences

Place of publishing:



ill. ; 24 cm

Type of object:



Woodash glass characterized by potassium plus calcium instead of sodium plus calcium was the major type in European Medieval glass production. The exhaustion of sodium-based raw materials from Egypt caused a change to local sources during the Carolingian period. With the invention of Gothic architecture, glass production and the number of glasshouses increased, but the technical experience was limited, the glasshouses working at the lowest possible furnace temperature of 1200 degrees centigrade which required the high potassium concentrations of beech trunks instead of bulk trees. The latter sources with high calcium concentrations characterized the early and late Medieval glass production at higher furnace temperature. Lack of woods in England and France had to be compensated by mixing woodash with fernash. The late Medieval total production of glass panes in Germany was in the range of 30,000 tons


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Archaeologia Polona



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Resource Identifier:



IAiE PAN, call no. P 357 ; IAiE PAN, call no. P 358 ; IAiE PAN, call no. P 356 ; click here to follow the link



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Copyright-protected material. May be used within the limits of statutory user freedoms

Digitizing institution:

Institute of Archaeology and Ethnology of the Polish Academy of Sciences

Original in:

Library of the Institute of Archaeology and Ethnology of the Polish Academy of Sciences



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