Real pearls are a precious gemstone made by oysters, mussels and various other bivalve mollusk species. Most real pearls today are cultured or farmed, by inserting material into a mollusk, after which the mollusk lays down concentric layers of nacre until a pearl is formed. The iridescent nacre is the hallmark of a real pearl.
Fake pearls are made up of glass, ceramic, shell or plastic to give them the appearance of real pearls. This fake pearl is often painted and covered in a material that simulates a pearl-like luster and false iridescence. They are manufactured by humans to fool the human eye. 99% of fake pearls are low quality, only suitable for costume jewelry. While Mallorca or Majorica pearls are marketed as a high-end alternative to real cultured pearls.