These original collotype are on heavy wove paper, printed in black/gray ink 1908-1914 by the publishing house H.O. Miethke. Signet (intaglio-printed in gold ink) in lower margin, center.
In 1908, Klimt undertook a unique and important collotype project, being a limited edition titled “Das Werk Gustav Klimts”, completed in 1914. The prints depict Klimt's most important paintings from 1898 to 1913. Klimt closely supervised production of the portfolio, which was overseen by the prestigious Galerie Miethke, his exclusive art dealer in Vienna. A complete set of “Das Werk Gustav Klimts” (the Work of Gustav Klimt) contained 50 prints on heavy wove paper with deckled edges. Issued unbound, the prints were divided into five groups of ten, each group published separately over a period of six years and sold only by subscription through the publisher, H.O. Miethke. “Das Werk Gustav Klimts” demonstrates the remarkable ability of the collotype process to render gradations of tone, color and texture. All sheets and most of the images are in a square format, with the remainder in the narrow rectangle format derived from Japanese paintings and woodblock pillar prints. Klimt designed a unique signet for each print, to be centered beneath the image and impressed in gold ink. Today, images from this portfolio, printed during Klimt's lifetime, are quiet rare and in high demand, as indicated by a recent sale at $20,400 of a single print ("Water Serpents I") from this portfolio at Treadway/Toomey Galleries, 3/8/2009, lot 638.
Collotype is a dichromate-based photographic process originated in Germany circa 1868 and was used for large volume mechanical printing before the existence of cheaper offset lithography. It can produce results difficult to distinguish from metal-based photographic prints because of its microscopically fine reticulations which comprise the image. Many old postcards are collotypes. While no longer a commercial process. The collotype plate is made by coating a plate of glass or metal with a substrate composed of gelatin or other colloid and hardening it. Then it is coated with a thick coat of dichromated gelatine and dried carefully at a controlled temperature so it 'reticulates' or breaks up into a finely grained pattern when washed later in approximately 16 °C water. The plate is then exposed in contact with the negative using an ultraviolet (UV) light source which changes the ability of the exposed gelatine to absorb water later. The plate is developed by carefully washing out the dichromate salt and dried without heat. The plate is left in a cool dry place to cure for 24 hours before using it to print. To produce prints, the plate is dampened with a glycerine/water mixture which is slightly acidic, then blotted before inking with collotype ink using a leather or velvet roller. A hard finished paper such as Bristol, is then put on top of the plate and covered with a tympan before being printed typically using a hand proof press.