Anthropometries of the Blue Period and Fire Paintings

The performance piece, Zone de Sensibilité Picturale Immatérielle, took place between 1959 and 1962. In this work, Klein offered empty spaces in the city for gold, challenging buyers to engage with the concept of The Void. This unique exchange involved providing a certificate of ownership, blurring the lines between art and commerce.

In a follow-up performance on the Seine, Klein invited a critic to witness the burning of the certificate in exchange for throwing half the gold into the river. This act aimed to restore the "natural order" that had been disrupted by the sale of empty space. The remaining gold was used to create a series of gold-leafed works, adding to his blue monochromes and reflecting his evolving artistic vision toward the end of his career.