"Chimigramme"

gelatin silver chemygram (paint with chemistry on baryta paper)

The chemygram, which is similar to the photogram and the luminogram, is a primary form of the photographic image. It is based on the reaction of photosensitive paper with developer and fixer and therefore on photochemical reactions, combining the physical properties of color (oil-varnish, wax, oil) with the chemistry used in photography (photosensitive layers, developer, fixer)—without a camera, enlarger, and via natural daylight.

Belgian native Pierre Cordier is the initiator of the chemygram, the first was created in 1956. In 1963 the term became protected by copyright. Without ever using a camera, Cordier produces photographs merely by utilizing and influencing the process of the photochemical reaction on photosensitive paper in the time of developing and fixing.
 The principle of randomness, that is of great importance in his oeuvre, opens numerous possibilities for creation.
https://www.photoeditionberlin.com/artists-1/pierre-cordier-gundi-falk/