. "rare blue pigment" . . . "International Klein Blue" . "monochrome blue paintings" . "Klein" . "IKB1" . "Klein Blue" . . . . "International Klein Blue (IKB)" . "ultramarine" . . . "002FA7" . . "Yves Klein Blue" . . . "Klein-blue" . . . "Yves Klein blue" . . "International Klein Blue" . "blue art" .