An antique Art Nouveau Favrile miniature glass vase after LCT Tiffany. Gold and silver luster with beautiful green and pink iridescence coloring on crumpled shape of the vase. Tiffany patented the Favrile glass in 1892. Favrile glass often has a distinctive feature characteristic of classical antiquity glass: it has a surface iridescence. This iridescence gives the surface a shimmer, but also some opacity. This rainbow glass effect was obtained by mixing different colors of glass in hot form. Collectible Art Glass Ware, Art Nouveau Decor For Interior Design.