The “wing oysters”, genus Pteria, are
characterized by a more elongate shape than
Pinctada spp., being longer (anteroposteriorly)
than wide (dorsoventrally). The posterior ear
is often greatly prolonged (Velayudhan and
Gandhi, 1937). Pearls themselves have always
been objects of great value and have
symbolized love, chastity, purity or feminine
charms in various societies. Good quality
natural pearls are rare and therefore extremely
valuable. The history, distribution and
importance of the pearl as a gem are described
in Kunz and Stevenson (1908), George (1978)
and Ward (1985). George (1978) believed that
W. Saville-Kent produced the first spherical
pearls in the 1890s from P. maxima. Patents
were first filed independently for the procedure
by two Japanese, Dr. Nishikawa and T. Mise
who were believed to have had knowledge of
the techniques of Saville-Kent. The first harvest
in 1976 of 6 kg of pearls was worth US$ 80,000
(US$ 13,333/kg). By 1983, black pearls were
French Polynesia’s top export earner and in
1989 exports to Japan were worth US$ 41.1
million CIF
The “wing oysters”, genus Pteria, arecharacterized by a more elongate shape thanPinctada spp., being longer (anteroposteriorly)than wide (dorsoventrally). The posterior earis often greatly prolonged (Velayudhan andGandhi, 1937). Pearls themselves have alwaysbeen objects of great value and havesymbolized love, chastity, purity or femininecharms in various societies. Good qualitynatural pearls are rare and therefore extremelyvaluable. The history, distribution andimportance of the pearl as a gem are describedin Kunz and Stevenson (1908), George (1978)and Ward (1985). George (1978) believed thatW. Saville-Kent produced the first sphericalpearls in the 1890s from P. maxima. Patentswere first filed independently for the procedureby two Japanese, Dr. Nishikawa and T. Misewho were believed to have had knowledge ofthe techniques of Saville-Kent. The first harvestin 1976 of 6 kg of pearls was worth US$ 80,000(US$ 13,333/kg). By 1983, black pearls wereFrench Polynesia’s top export earner and in1989 exports to Japan were worth US$ 41.1million CIF
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