Emil Mariot 1867 "heliogravure" proccess.. "A photographic gelatin relief was transferred to a silver-surfaced copper plate, whereon an intaglio printing surface was produced by photogalvanography." (Mertle pg. 23) The process may have also been used for photographs as this one example exists. [1]

This book is a history of Photogalvanography by Pretsch, with full instructions and contemporary uses as well as discussion of other modifications, such as Mariot’s. Two samples of Mariot’s process, one a photogravure plate produced in 1869 and a photogravure portrait of Pretsch, 2 Photogalvanographs from Pretsch plates, one intaglio, one relief (both art), 2 Mariot Photo-Galvanogravures, one of scenery from 1869, one a map, 3 half-tones by Husnik, one from art, 2 from life.