Many people fall in love with pearls. Possibly it has something to do with the fact that the pearl is coated with mother-of-pearl or, as it is known, nacre. Certainly a natural or cultured pearl is a thing of beauty.
As the shellfish sits statically in the water, it pumps a never-ending flow of water through its body. Occasionally a tiny parasite or a piece of grit is ingested and the shellfish triggers a flow of calcium carbonate, called nacre, to coat the intruding article encasing what will, in time, form a pearl.
Nacre is the substance that coats the inside of the shell as well. It is made up of tiny pieces that form layers thus coating not only the shell but the intruding particle. It is strong, iridescent and resilient.
Man has managed to duplicate this process by opening the shell and carefully inserting a piece of shell …