A jeweler with an established reputation through the world, Louis Comfort Tiffany was the spearhead of the Art Nouveau movement in the United States. At a time and in a country in perpetual growth, Tiffany succeeded in elevating the decorative to the rank of fine art. Glass was the field of expertise of Tiffany▓s workshops. There they developed groundbreaking techniques of treatment which produced beautiful effects on glass. Following the examples of Gall? or Daum, Tiffany made the most of this material: playing with colors, opaqueness and transparency... However, his most famous success is his lamps in mosaic of glass, similar to the cathedral▓s stained glass window. Diving into this prism of colors, the author makes us dream again of the birth of this enduring company.