ADOM (Association pour la défense de l'oeuvre de Joan Miró) has confirmed the authenticity of this work.
The monotype technique has long been favored by modern artists, from Edgar Degas to Henri Matisse, from Pierre-Auguste Renoir to Joan Miró, for its unique blend of original and printed imagery. In the process, one (mono) image is rendered in ink or paint directly onto another surface capable of transferring the medium, via press or hand rubbing, to its final support (paper, in the present instance). Fascinated by the potential for manipulation and serial exploration, Degas, its first 'modern' champion, ultimately produced over 400 monotypes. In Composition, Miró worked the transferred plane over extensively, using oil, ink and charcoal to achieve its vibrantly layered effect. The rectangular outline framing the center of the composition represents the imprint left by the plate from which Miró transferred the initial image.
Like Degas, works on paper became increasingly important in Miró's final years. As his friend Jacques Dupin has written, "Though Miró was enamored of all his materials, his passion for the infinite richness of paper was undoubtedly more lively and enduring than all others... These sheets of paper were the main support for his research and experiments. They were the thread of his momentum, and of his wanderings. They also grounded his most advanced works, carried out from day to day, haphazardly or with determination. As opposed to his work on canvas or his object-works, Miró's reactions on paper are livelier, and the sheets are a sort of travel-log revealing the painter's desires" (Jacques Dupin, Miró, Paris, 2004, pp. 355-356).