Myth: Pearls are made from a grain of sand

V&A dissolves myths around pearls in major new show
The Guardian

[Marilyn] Monroe and [Elizabeth] Taylor are represented in a show devoted to pearls, opening at the V&A on Saturday.

Neither probably knew the grimmer truth of what they were wearing. "The pearls are formed around the larvae from a tapeworm coming from the excrement of other animals," said the show's co-curator, Hubert Bari. "The people marketing them prefer to say 'it is so fantastic: your necklace was made from a grain of sand'. It is better to speak about a grain of sand than to speak about a piece of shit from a stingray."

The grain of sand myth is so entrenched that the V&A has included a video showing precisely how pearls are formed – how tiny tapeworm larvae that live in the digestive systems of animals such as sharks and stingrays are excreted and then, very rarely, manage to get into water-filtering shellfish. Some get trapped between the shell and the outer epithelial tissue, and it is from this that the pearl emerges and the larvae dissolves.