Unique etched and inked steel plate with gold by the process of Charles Négre. Honoré Théodoric d’Albert, Duc de Luynes by Louis Auguste Bisson 1867
Notice sur M. le Duc de Luynes, membre de l’Institut, representant du peuple aux Assemblees constituante et legislative, de 1848 a 1851. Huillard-Bréholles, Jean Louis A. Published by Henri Plon, Paris, 1868 contains albumen portrait of Luynes that matches the Negre plate.
While the common material for his plates was steel and the common application was intaglio printing, Nègre’s patent details numerous potential materials, applications, and modifications that characterize his process as inherently flexible and versatile. This includes the use of photographic negatives, positives, inverted negatives, or inverted positives on either paper or glass as the initial images; the creation of intaglio plates, relief plates on copper or steel, as well as lithographic plates on zinc; the decoration of metal with photographic images in a wide variety of colorized metal transferred by galvanoplasty imitating the effects of damascening, niello, or encrustation. The patent lays out this complexity, defining the reach of his process not only for visual reproduction, but also for material transformation. Lewis
Lewis JW. Charles Negre in Pursuit of the Photographic. 2012.