Bismuth painting
Bismuth painting is a historical arts and crafts painting technique from the 16th to 18th centuries. Various museums present wooden panels, boxes or chests decorated with this technique, most of which come from southern Germany. Typical motifs are colorful ornaments, flowers and figures. They stand on a shiny metallic background, mostly tarnished in color due to oxidation.
This bismuth base consisted of pure unalloyed bismuth in a box from 1557, chemically examined by F. Wibel . Since the brittle bismuth cannot be beaten into thin foil like gold and silver, it is assumed that powdered bismuth bound with glue was applied to a hard chalk base. Subsequent processing with polishing steel or the agate polishing stone initially created a precious-looking surface reminiscent of silver, which was finally painted decoratively. Covered with gold lacquer, a poliment gilding could also be simulated. This or a transparent lacquer coating protected the bismuth from oxidation, which, however, was often desired because it created an iridescent tarnish color . This so-called luster color played a special role in bismuth painting. A play of colors ("rainbow colors ") appears on the thin oxide layer due to the interference of the incident light, similar to an oil stain on water. After polishing the bismuth layer, you could paint on the shiny ground with tempera or oil or lacquer.
In the 15th and 16th centuries, bathers in particular bought woodwork as a souvenir, painted “as you know with the bismuth” . Since 1996, courses to revive bismuth painting should be initiated in Wildbad .
"Systematic research and material reconstructions" took place under Kurt Wehlte , founder and teacher at the Institute for Painting Technology at the State Academy of Fine Arts in Stuttgart. In his second edition of the “Painting Bible”, published in 1967, he mentions Joseph Sutter, who “in 1920 reconstructed bismuth paintings according to the information provided by Munich chemist Prof. Georg Buchner”.
As a result of this work, Wehlte describes the production ( precipitation ) of "bismuth sponge" (p. 745). This gray, slimy sediment of flocculation bound with rabbit glue can be applied with a brush in several thin layers on a chalk base, as is the case with poliment gilding known, apply and polish after drying.
Individual evidence
- ^ Wildbad, a stronghold of bismuth painting in the 16th century. Fritz Barth on bismuth painting
- ↑ Kurt Wehlte: Materials and Techniques of Painting. with an appendix on color theory 1977, ISBN 3-473-61157-3 , p. 744