According to David Lancaster in the book "Christie's Art Nouveau Jewelry", Art Nouveau was characterized by sinuous lines, guilloche enamel and opals. It was "a style that gripped France in the mid-1880's, spread through Europe and America, and faded prior to WWI." The book goes on to say that "In Britain, the drive to reject all machine work led beyond Art Nouveau to the Arts and Crafts Movement, an impractical approach to the commercial manufacture of jewelry. Along with dreams of diaphanous beauty and peace these ideals were all swept away by the brutality of the 1914-18 war, to be replaced by machine-inspired modernist lines leading to Art Deco.
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