My pattern and my photos of flowers and an Art Deco Van Cleef & Arpels brooch (Ruby, sapphire, diamonds) dating of 1920/1930. This stylised flower reminds me of a carnation (œillet in French). Stylised figurative designs were also popular in the Art Deco period (1910-1939) : flowers, leaves, fountain, half moon, stylised animals, shells, stylised…
Sources : futura-sciences, collection-mineraux
The four gemstones are ruby, diamond, sapphire and emerald. Ruby and sapphire are corundum stones while emerald is a beryl and diamond is a carbon. Source : https://www.futura-sciences.com/sciences/definitions/matiere-diamant-3869/
Art Deco illustration, ruby and diamond fan double clip brooch by Van Cleef & Arpels (1937) and my pattern.