No. While pearls may resemble the lustre of their host pearl oyster, their structure is fundamentally different from that of mother-of-pearl. Mother-of-pearl is formed from thousands of flat layers of nacre laid over a natural protective base outside of the flesh of the oyster.

A pearl, by contrast, is created within the organic flesh of the oyster, where nacre builds concentrically around a nucleus. This rounded form, and the absence of a protective base, allows light to be both reflected from the surface and refracted through the pearl’s inner layers, giving pearls their translucent appearance.

Mother-of-pearl from saltwater nacreous molluscs is naturally resilient, owing to its structure of thousands of layers of nacre bound by organic compounds. While softer than many gemstones, it is a strong organic material that, when cared for, can endure for generations. Exquisite antique mother-of-pearl jewellery from ancient civilisations can still be found in museums today.

While pearls are formed from the same organic materials as mother-of-pearl, a pearl itself is one of nature’s most resilient structures. Built from thousands of concentric layers of nacre, it may be easier to scratch than a diamond, yet far tougher under impact. A diamond may shatter when struck; a pearl will not.

By contrast, pearls and shells from many freshwater molluscs and clams tend to deteriorate rapidly once exposed to air, often requiring chemical treatment to slow this process.

Mother-of-pearl refers specifically to the nacreous inner lining of certain mollusc shells, such as pearl oysters. It is this nacre that gives mother-of-pearl its distinctive iridescence and intrinsic value. 

Shell, by contrast, describes the outer layers of a pearl oyster, as well as both the inner and outer layers of many other molluscs that do not produce nacre. Numerous molluscs—including non-nacreous freshwater clams—form shells without any nacre at all. 

Mother-of-pearl can be worn regularly with mindful care as with many other precious materials. To preserve its surface and lustre, avoid prolonged exposure to harsh chemicals or impact against hard surfaces.