bijou vs pearl necklace

bijou

noun
  • A piece of jewelry; a trinket. 

  • A jewel. 

  • A small intricate piece of metalwork. 

adj
  • small, little (often implying affection) 

  • intricate; finely made 

  • small and elegant 

pearl necklace

noun
  • Used other than figuratively or idiomatically: see pearl, necklace. 

  • A sexual act whereby semen is ejaculated onto a partner's upper chest, breasts and/or throat. 

How often have the words bijou and pearl necklace occurred in a corpus of books? (source: Google Ngram Viewer )