The San Francisco call., 1903-12-20
UNCLE SANS
PEARL STATES
Wisconsin, Tennessee and Ohio
Fisheries Furnish the Bulk
of All the Pretty Gems
SOME OF BEAUTIFUL TINTs
Mound Builders of America
Buried Bushels of the Costly
BaubleS in Their Monuments

4
/ the best varieties outrank the diamond
in value. This increased value is ac-
! counted for by the fact that the supply
| is far from equal to the demand. while
| the demand has been largely caused by
the dictate of fashion Formerly ma
rine pearls furnished four-ifths OF the
available supply, but these fisheries
] have gradually fallen OF until now they
produce only about three-fifths Of the
yearly yield. the rest being made up OF
/ fresh water pearls. a considerable part
of which are found here.
In this country fresh water pearls are
generally found in bivalve shells Of the
/ family unionidae, also known as the
| naiades. These mussels are most
abundant in swift and clear water
where the bottom is sandy or gravelly
and the country rock calcareous- The
pearls found are few, and those OF mar
ket value represent the destruction OF
/ thousands of mussels for every one OBJ
| tained. The soft internal parts OF these
mollusks are covered by a thin. delicate
membrane called the mantle, from the
surface and particularly from the outer
edges OF which material is excreted 70
from the inner layers Of the shell.
Whenever by accidental injury, disease
or intrusion of foreign substances local
irritation is set up in these tissues the
effect is to produce an increased secre-
tion of the nacreous matter at this
| point. resulting in the formation Of
pearls or pearIy concretions.
KINDS OF PEARLS.
Pearls are Of several distinct kinds,
differing in shape and perhaps in ORR
gin. Free" pearls, those that are
/ found loose and separate between the
folds or layers of the mantle and gills,
or between the latter and the body Of
the mullusk, comprise most Of the true
spherical pearls, as also many that are
ovate. pear shaped and irregular. Then
there are the pearls found between the
mantle and the valves Of the shell;
these, if free at all. are apt TO be hemi-
spherical, or in any case 1attened on
the side toward the shell, while often
they are attached more or less TO the
| valve by a deposit Of the pearly secre-
ton In the region of the hinge these
become extremely irregular in shape
and often greatly elongated, forming
third kind, known as hinge pearls, ba-
Foques, etc.
/ The freshwater pearls differ from the
marine pearls in their greater variety
of tints and in the partial transparency
/ of their nacre- In color the freshwater
/ pearls present an extended series Of
/ shades, from dead Opaque white. hav-
/ ing little value, through various tints
/ of pink, yellow and salmon. or faint
purple passing to a bright red, so close
< ly resembling a drop Of molten copper
4 as almost to deceive the eye. Some are
very light green and brown, others rose
/ color and still others are pale steel
/ blue, russet and purplish brown. In
/ addition to their color and Iuster they
are beautifully iridescent, and at times
the white and pink pearls are more lus-
/ trous than even the best oriental pearls
ODD SHAPES.
/ Many oddly shaped pearls are found.
/ Elongated fishlike forms found near the
/ hinge of the shell and called hinge ba-
/ rogue pearls are abundant Others,
with a slight addition Of gold and enam-
/ el, may be made to represent human
and animal heads, bat and bird wings
and similar objects. A pearl was found
in this country that strikingly resem-
/ bled the bust of Michael Angelo. In a
/ few instances small fishes and crabs
which entered the shell have been i'm
/ prisoned and covered eventually with
nacre, thus making pearls Of them, at
/ the same time retaining the animals
/ shape
/ Frequently pearls have an opaoue
/ appearance and seem to be worthless.
but on the removal of their outer layer
are found to be clear and iridescent
/ The outer layer may be removed by
! dipping them in a weak solution of
acid, which dissolves the opaque coat
\ ing, or it may be peeled with a knife
| like an onion, although this is hazard
/ Gus, as sometimes the pearl is not Of
/ the same material throughout and can
not be restored after being peeled.
/ Examinations which have been made
of some Of the mounds of the Missis-
sippi Valley, particularly In the Miami
and Scioto valleys in Ohio, have re-
vealed the fact that the long forgotten
race that erected these remarkable
structures gathered and used the
] fresh water pearls to an astonishing
! extent. Bushels Of pearls have been
found on the hearths of some OF these
Ohio mounds These are, OF course.
worthless, as they have been damaged
and half decompOsed by centuries of
| burial and by the heat of sacrihciaI
fires An idea of the quantity found in
| certain of these mounds may be gath
cred from the fact that all the pearls
which have been found in the recent
years of search and excitement would
not approach in numbers those found
/ in any one of these mounds. It is prob
able that the mound builders used the
mussels for food. and thus naturally
accumulated large numbers Of pearls.
/ which were probably used for orna-
ments-
SPANISH EXPLORATIONS.
The Spanish explorers who accom-
panied De Soto in his memorable ex-
pedition from Florida to the Missis-
/ sippe in 1910. gave many remarkable
accounts of the pearls seen and pro-
cured from the natives with whom
i they came in contact in their extensive
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