Carborundum printmaking
Carborundum mezzotint, or carborundum aquatint, is a printmaking technique in which the image is created by adding light passages to a dark field. It is a relatively new process invented in the US during the 1930s by Hugh Mesibov, Michael J. Gallagher, and Dox Thrash, an artist working in Philadelphia with the Works Progress Administration (WPA)).