National Geographic : 1997 Jun
t the turn of the century the pearl fisheries of Polynesia har vested oysters just for the iridescent inner shell, mother-of-pearl for the world's buttons. Back then a pearl was an exotic windfall. Today nearly every pearl on the world market is cultured, grown by man. At another of Wan's farms, I marveled at the pearl farm ers' ingenuity. They use plas tic garlands suspended in the lagoon to provide an anchor age for the drifting pinhead size larvae. In a few months each garland is choked with little oysters (bottom far left), which soon grow to the size of silver dollars. At six months the oysters are placed in hanging baskets (left), where they grow for another year and a half. Then the oysters are removed and wedged open, one by one. With surgical precision, grafting operator Tsunoda Kunitoshi (bottom center) makes a slit with a scalpel near the oyster's gonad and inserts a snippet of mantle tissue, followed by a nucleus (bottom right) -a bead carved from the shell of an American fresh water mussel. The mantle tissue forms a sac where nacre-the pearl escent substance that coats the nucleus to form a pearl is generated. After surgery the oysters are returned to the lagoon. In three years the pearls will be ready to harvest.