Johann Andreas Cramer and Chemical Mineral Assay in the Eighteenth Century

Although little studied now, the work of Johann Andreas Cramer (1710-1777) on mineralogy and metallurgy was much appreciated by his peers and influenced the development those fields throughout the eighteenth century. Well versed in the theoretical and practical problems of analysing and grouping minerals, Cramer sought to solve them by formulating a new, accurate system for identifying and classifying metals. He also developed faster and less expensive metal extraction methods than those previously available. This paper traces the chemical ideas that underpinned Cramer's novel methods, including the theories of Hermann Boerhaave and Georg Ernst Stahl, and shows where Cramer both followed and departed from these authorities in his own influential Elementa Artis Docimasticae (1739). In the process, I seek to map Cramer's scholarly network in order to contribute to a more thorough understanding of the communication of chemical ideas and procedures in eighteenth-century Europe.