BARCELONA.- Shown in the Engraving Exhibition Rooms of the museum is a selection of lithographs by Picasso developed between 1945 and 1956, when the artist really developed his interest in this printmaking technique. As he usually did when exploring a technique, he used several kinds of plates – stone, zinc, transfer paper – and tried a variety of traditional media – grease pencil, pen, wash -as well as introducing new materials and radically transforming the old established practices of the craft. One of the characteristics of Picasso’s lithographic work is that he tended to subject a given subject to numerous interpretations and variations. Some of his lithographs were taken through eighteen states; in other words, the image represented underwent eighteen mutations.