“Art nouveau (Art nouille) is a style of decorative art, architecture, and design prominent in western Europe and the USA from about 1890 until the First World War and characterized by intricate linear designs and flowing curves based on natural forms.”
Poppy is a floral pattern often used by Art nouveau artists (illustrators, jewelers…) like Mucha, Maison Vever and René Lalique.
Mix of Art Nouveau poppy illustrations and Alphonse Mucha’s illustration (second poppy illustration), JAR’s (Joel Arther Rosenthal) poppy jewelry (Pink and Green tourmaline, diamond brooch,1982)
More Mucha’s poppy illustrations :
William Morris’ poppy illustrations :
Mary Golay poppy illustrations :
The Art Nouveau artist René Lalique poppy jewelry :
Maison Vever poppy jewellery :
The Art nouveau inspired jeweler Larissa Podgertz poppy jewelry :
The Art Nouveau inspired jeweler Ilgiz Fazulzyanov poppy jewelry:
The Art Nouveau inspired jeweler Michael Michaud poppy jewelry :
Sources : Oxford dictionary and Pinterest