Semi-weekly south Kentuckian. [volume] (Hopkinsville, Ky.) 1883-1889, 1888-01-20
PRECIOUS STONES.
How the GenifIte and Undesle So Arv
6c and Set. us~'A

How the GensfI<e and Underll1 s,sE1- Arv
66t. and Set. uk~llA
Crystalline gems, like diamond and
topaz, are genersnR cut in such
manner as to have nat, smooth faces.
Precious stones thai ,Siecompose tho
light and thus produce play of
colors. are polished in such a way as
to hoightcn this effect as much as
possible. which Is accomplished by |
making large number Of small |
facets. The brilliant is IN example.
Precious stones that do not crystal
lie, and are distinguished by play OF
colors. like the opal. or peculiar effects
Of light, like the cats-eyc. are usually
polished round or oval, like loaf OF
bread or half Of egg.
Gems are set in two different ways,
distinguished as free setting and
band setting. In the former the stone
Is exposed on all sides and only held
by little clasps. All its properties, its
fire, its play Of colors, show 10 the best
advantage here. Hence very vald-
able stones nrc never set in any other
way.
Flat stones that are set In rings are
sometimes fastened on the edge so NJ
TO leave only the top and bottom sur
faces exposed. In the band setting
the stone forms the lid Of gold box,
and il tho gem is transparent the up.
per surface is generally made fiat aud
smooth, while the under side forms a
T low pyramid.
In those stones which receive band
or box setting, and are less valuable,
the beauty Of the stone Is increased by
lining the box with colored tinfoil, the
color Of the foil corresponding to that
/, Of the stone. Thus for example, a
piece of dark-yellow foil is placed I'M
. der a very pale topaz. a deep purple
: foil under pale amethyst, and SO on
i so that tho light reflected from be-
n meath through the stone will have a
h deep yellow or violet color, giving Tho
!. stone a much finer appearance than i
II il were set free.
J. When setting common stones II
!, cheap goods, they do not take thu
:. trouble 10 limo tho box with tinfoil
! bat merely give 1t a coat Of some oil
ored yarnish. This method is not one
20 be recommended, for stone thai
II has the foil beneath 1t looks mucl
t. handsomer.
a In order to make a cheap articl
J. with eenuine stones. the following In
7, renious device is resorted to: Thil
/ slips Of some gem, as emerald, for ex
,. ample, are backed up with glas
y Of exactly tho same color. and tn
:, glass likewise polished. BY setlini
~ ono Of those double stones with tn
n stono outward and the glass beneath
\. the surface will, Of course, exhibit al
70 tho properties Of the gem, such q
e hardness aud brilliancy.
These half-genuine stones are know
70 rs "undealaid gems" When they ar
d skillfully set. 1t is difficult even for tn
p, expert to distinguish them from per
fectly genuine stones But still, 1t !
re- easy to distinguish thon by holding
p the stone before the ego in such n man
a. ner that the light reflected from til
i Top enters tho eye at an obliqe angle
!, The surface where the s tono and glas
e. meet can be distinctly recognized b
q, the difference in tho retroactive powe
4. Of tho two media having the appear
P. ance Of a crack or flaw in the stone
n, Tho public arc frequently deceived b
dealers who represent these underlai
z. stones as being perfectly genuine.
IA Golden Days.