Pearl abalone

Natural or oriental pearls are produced naturally by bivalves, such as oysters and clams, and by a few gastropods, such as abalone. Cultured pearls are induced by the introduction of foreign objects into the mantle cavity. Modem cultured pearls are usually seeded with a sphere made from the shell of Mississippi River mussels (family Unionidae). The culturing process involves prying open the shell and inserting both the seed or nucleus that will become the core of the new pearl, and a piece of donated mande tissue from another oyster. 

Abahme pearls from the abalone, of the genus HaHmiSi are unusual in that th come fixim the group of molluscs called gastropods, and not from bivalves. The molluscs have only one shell (see Chapter 10,... 

Shell )- The pearls are iridescent, with the same blues, greens, purples and pinks that are displayed by the shells. The pearls are natural, and are usually hollow and of unusual shape - often cusp shaped - and very seldom round (F%. 9.8). Nowadays cultured composite blister pearls are being produced in abalones. 

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