A YELLOW AND BLUE SAPPHIRE 'PASSE-PARTOUT' FLOWER BROOCH BY VAN CLEEF & ARPELS,
circa 1940, the stylised flowerhead of cushion-shaped mixed-cut yellow sapphires enclosing a bombé cluster of circular mixed-cut blue sapphires, framed by leaves and further graduated blue sapphire accents, signed Van Cleef & Arpels, with French eagle's head control mark and single pin fitting, length 4.8cm
The Passe-Partout was patented by Van Cleef & Arpels in 1938 and represented one of the first examples of transformative jewellery pioneered by the jewellery house at that time. Intended to adapt to a wearer's mood or occasion, the Passe-Partout range comprised a flexible yellow gold snake chain and two gem set flower clips, inspired by the Hawaii collection, set with different coloured sapphires and rubies. These could either be worn separately or together as a necklace, bracelet or belt, using a system of metal rails to adjust the chain, which were concealed by each of the flower clips.