Pearls are created by implanting a nucleus into the gonad of the oyster. The oyster protects itself from the foreign particle by coating it in a translucent substance called nacre. Over time, layer upon layer of nacre builds up around the nucleus, forming a pearl. Water purity and temperature have a great influence on the quality of the nacre, and hence the quality of the pearl. Australian South Sea pearls are grown in a unique environment and are amongst the largest and most valuable pearls in the world.
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