appearance
of hematite, nor the polished shine of the black clam pearl. Black
pearls having a bronze effect are open to suspicion, especially if they
are pierced, as many of them are artificially colored and are liable
to fade. Such pearls have a somewhat metallic appearance, are seldom
very lustrous, and if there is a rough chalky place in the skin it will
be blacker there than elsewhere.
It
is difficult to give rules by which to judge color, but there is a
quality which can only be described as " clean." It is free from
muddiness and is desirable in pearls as in all other gems.
The
proportion of fancy colors is greater in fresh-water pearls than in the
orientals. In the United States the fisheries which have yielded the
finest "fancies" are those of Wisconsin, Kentucky and Tennessee. Of sea
pearls, most of the fine black ones come from the coasts of Mexico.
Beautiful colored pearls are found in fisheries of the Oceanic Islands,
for instance at the Isles of New Caledonia and Gambier, and in China
and Japan.
To make close comparisons of color in pearls, place them on white cotton under or opposite
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