Yves Klein (1928-1962), Monochrome bleu sans titre, (IKB 328), 1959, pure pigment and synthetic resin on cartoline, 21.3x17.3 cm The work was registered in the Archives Yves Klein in 2025 Provenance: Gérald and Muriel Minkoff Collection, Geneva Very good condition The leaf is loose in its frame, supported only by 4 small tabs in the corners on the reverse The leaf is flat There are no visible traces of restoration There are a few small losses: - along the top left-hand edge for approximately 2 cm - in the inner corners, a small micro-mark towards the centre, smaller than 1 mm². Slight dusting, very good adhesion of the pigmentation To the best of our knowledge, this work has never been seen before on the art market Very good overall condition The paper is free within its frame, held only by four small tabs at the corners Good planarity of the sheet No visible signs of restoration noted Presence of small losses: - along the upper part of the extreme left edge, approximately 2 cm - in the inner corners, a small micro-loss near the lower center, less than 1 mm² Light surface dust, very good adhesion of the pigmentation Yves Klein (1928-1962), Monochrome bleu sans titre, (IKB 328) Produced in monochrome using a specific pigment developed by the artist, International Klein Blue (IKB), the painting presents a surface of impressive luminous intensity and depth. This blue, which he patented in 1960, is obtained by combining pure pigments with a synthetic binder that fixes the colour while preserving its brilliance and characteristic matt appearance. This vast expanse of uniform blue makes the colour itself the sole subject, without any figurative representation. The application of the pigment highlights the texture of the surface, playing on its materiality while exploiting blue's ability to capture light. This work is part of the artistic approach of Yves Klein, an avant-garde figure of the 1960s, who made monochromy a central focus of his research. His work is part of the New Realism movement, characterised by a desire to renew the relationship between art and reality by breaking free from the codes of traditional figuration. By developing and patenting International Klein Blue, Yves Klein also set an important milestone in the history of contemporary art, having a lasting influence on the practice of pure colour as an autonomous means of expression.