In Yerseke, Zeeland, a small Dutch fishing village, Hannah van den Boomgaard crunched on something hard while eating oysters only to realise she had found a twin pearl, two pearls grown together, which look like a big tooth or even a good luck doll, as Van den Boomgaard said herself.

Earlier this year in Arnhem a chef found a pearl in an oyster, which was rare, but the double pearl is of course, even more rare.

Oyster make pearls around grands of sand or other irritants as self-protection using nacre, the same substance its shell is made of, but then usually round. Cultured pearls are made by putting irritants in the oyster so that they will produce a pearl around it.

(Link: www.rtlnieuws.nl, wonderopolis.org)