Potash glass
In potash glass is glass that using potassium carbonate as a flux was produced. In the more recent literature, too, this glass is often equated with wood ash glass or forest glass in general. This must be viewed at least partially as incorrect, since the production of potash has only been known since the 17th century. However, due to its composition, the term potash glass applies to both wooden and potash glass and should be understood as an umbrella term in contrast to soda glass .
Potash was obtained by evaporating suitable vegetable ash , mainly from beech or oak . With this material, a purer, more colorless glass melt could be produced than with the traditional, unprocessed raw material.
With the introduction of this process, however, the already considerable wood consumption of the glassworks increased many times over, as fuel was required for the ash ovens and the flux loses mass as a result of the process. For this reason, many companies continued to use simple wood ash until the 19th century.
The process was probably developed by Johann Rudolph Glauber around 1650 .
See also
literature
- A. Cherry: Cistercian, glassmaker and wood turner. Glassworks in the Ore Mountains and Vogtland and their influence on Seiffen wood art. (Münster / New York / Munich / Berlin 2005).
- S. Strobl: Glass technology of the Middle Ages. (Stuttgart 2002).