To celebrate the immense range of color in the Pantone Color Guides (and to promote the book to college students in Jakarta), Basheer Graphic Books commissioned a giant rainbow from Bates 141 Jakarta, spanning 8 meters and made from 5,000 chips.
The rainbow was designed and built by Bates 141 creative director Hendra Lesmono and art directors Andreas Junus and Irawandhani Kamarga. There isn't much more information available than that, but as far as I can tell from browsing Kamarga's photostream, it looks like the rainbow was made by laminating graph paper onto a multi-part wood frame, which then acted as a guide for precise color chip placement.
More shots of the rainbow and fabrication process after the jump.
via The Coolist