To me it looks like a combination of the brooch and the center part of the necklace.
--Previous Message-- : According to Feau de Ferand in his latest : article (magazine Royals Extra) about the : Dutch Peacock Parure is in addition to the : tiara, necklace, brooch and bracelet also a : devant-de-corsage. : : See the picture of Queen Wilhelmina below. : She is wearing the tiara and a : devant-decorsage or it the brooch from the : parure? : What do you think! : : I’m sorry if this is discussed before. : : : : : : :