The morning news. [volume] (Savannah, Ga.) 1887-1900, 1894-06-03
How the Stones Are Prepared So as to
Increase Thsir Seeming Value.
From the Pail Mall Gazette.

INV INC ZONES are prepared 30 ds 10
Increase Their Seeming Value.
From the Pail Mall Gazette.
The value of diamonds and other gems
depending mainly upon their bulk, the
efforts of the falsifers have been chiefly
directed to increasing the proportions.
The principal mode of so doing is known
as doubling" 1t was in. use in the
seventeenth century, and q case lately
before the law courts in reference TO a So
called rule shows that it is still flourish
ing. 1t consists in joining together with
cement portion of real stone
and an imitation so as TO
make the combination appear one
and indivisible. This can be done so
deftly that the initiated are sometimes
deceived, as the case referred to above
goes to show. 50 iong,as a com bination
OF this kind remains unset the expert dis
covers IL usually by close examination
OF the edges; when it is mounted in
ring, bracelet, or other setting recogni-
| ton IS practically impossible. This is
| the most common form of deceit in the
jewel trade. If some of the jewels priced,
| by noble and prinCely houses were taken
TO pieces and carefully examined. by an
expert the result might astOnish the
owners. Some surprising discoveries of
this kind have been made when family
| Jewels We're being remOunted.
1t IS TO guard against receptions of this
kind that jewelers. and dealers in precious
stones decline to buy gems in their set
tings. When the gem is unset it can cas-
| lily be subjected to an infallible test. 4
| stone about which there may be suSpic-
ion is dropped into dish of very hot
water. If it is a "dOublet" the cement
| quickly dissolYes and the component
parts fall asunder. But "doubletsp are
| also made in which the real diamond
| finds no place. The art of glass manu-
! facture has made many advance in re-
cent years, aud experieuceuhas taught
! those who make it their business
| to fabricate spurious gems that a
| better result and a closer imitation
| of the genuine article can be obtained
| by joining two pieces of glass of diverse
shades. 1t is managed in this way: The
! top portion of the false brilliant is made
| from glass in which there is a pale yellow
| or straw-colored tinge In the under side
of this socket is drilled into this socket
| is fitted a stem of glass of a light blush
shade. the result of the combination being
that the false stone CLEANS and sparkles
like gem of the purest water. The best
| limitations of this description are so effec-
tive that when wei mounted they deceive
all but the best judges.
| Among the tests used by dealers and
| lbMGlEES W dSCEENdlu llOb only JIG IedllbN
| but the quality of diamonds offered for
sale is that of resistance or hardness.
| Few professionals are without a case of
proved diamonds, graded according to
their degree of hardness All purchases
are tested by this scale, and their
| quality ascertained. 4 specially con-
structed microscope is used to distin-
| guish coloPs in stones. 1t has been stated
that diamonds are seldom bought by the
trade after they are mounted. They are
! generally taken out of the setting for in
| spection. This is more especially the
case if the stones are SO mounted that the
under portion is hidden One of the old
est tricks of the trade is to so color the
bed in which the stone rests as to change
the hue of the gem, For instance, aruby
| will glow with a deepeFand more intense
fire if the bottom and sides of the setting
wherein it is liked be coiored red. The
shade of stone can be altered or flaw
concealed by the skillful use of colors in
this way -Naturally-this device does not
deceive the initiated A perfect stone is
invariably mounted "a jour-" or so that
every part of it is visible.
The discovery of diamonds in South
Africa led indirectly to some clever de-
ceit by the dealers. Many of the South
Africa diamonds have a straw tint, which
has an unfavorabe effect ON their price
especially as experts believe. that it win
become more decided the longer the
stones are exposed to the air Some of
the more knowing dealers discovered
that by subjecting the tinted dia-
monds to bath of certain acids the OBJ
jectionable color was removed and the
gems became pure white. A number of
diamonds so treated were sold in Paris
and Berlin, and brought higher prices
than they would if they had retained their
| original color After exposure TO
the action of the air for a certain
time the original color returns, but by
that time they have passed out of the
dealers hands. The fraud was soon
found out by the trade, and they now
guard against imposition of such a char
acter by means of various tests. OF
these the most generally used are the
hot water bath and friction. If a dyed
stone be left in hot water for a few
minutes it resumes it original hue; of if
the gem be rubbed sharply on towel, or
even on the coat sleeve, its normal color
can be detected. These tests are simple
and efficacious and are in daily use.