(Image credit: COURTESY OF WARTSKI)The brooch is one of more than 250 spanning 3,000 years that the jewellery historian has assembled to celebrate Wartski’s 160th anniversary. (Image credit: Angela WEISS/AFP/Getty Images)Wartski’s show is full of fascinating juxtapositions that highlight the many functions and fashions of this most versatile jewel. (Image credit: Hemmerle, Munich)Nature was never more charged than in the designs of René Lalique, whose flowing birds, insects and flowers revolutionised jewellery with Art Nouveau forms. The geometry and flimsier fabrics of 1920s fashion inspired new styles of transformable jewellery, notably the double-clip brooch — the height of Art Deco chic. (Image credit: Private Collection)Leading avant-garde artists designed jewellery for their friends, among them Salvador Dalí and Jean Cocteau, who adopted the disembodied-eye motif for several brooches.