The Helena independent. [volume] (Helena, Mont.) 1875-1943, 1892-11-11
CONTEMPLATING GEMS.
Glass the Basis of 1mitation-Reai Gems
Produced Artihciatly.

Glass the Basis of 1mitation-Real Gems
Produced Artilcially.
."The finest imitation diamonds are made
out of rock crystal" said a Washington
dealer in precious stones. 1.-The basis OF
the most successful oounterfeits of all kinds
of gems il a pure. very dense and highly
transparent SOFT of glass, which is termed
paste in the trade. For false diamonds
this glass is simply cut and polished in
fac cts, while for initiating other stones,
such as rubies, emeralds. sapphires, etc.,
metallic oxides are used with it.
I'm manufacturing glass for such pur-
poses the processes employed AVE 70 pc
conducted with the utmost nicely. For
making even the best mirrors the necessary
silica is obtained from ordinary white
quartz, while common window panes are pro-
duced from sea sand to a large extent; butt in
this case. rock crystal is substituted, com
posing about SO per cent of the ingredients
Of the paste. To ID must be added - per
cent of carbonate of soda and due proper.
tions of oalcined borax, saltpetre and red
lead. All these things are reduced to the
finest powder, mixed. fused together by
heat in a c1ucible and cooled slowly.
"The density. transparency and beauty OF
the plate depend upon the care taken in
these processes. Thus made, it is all ready
to be cut up into diamonds and prepared
for market. 1t may be, however, that the
manufacturer desires to produce counter
felt gems of other sorts. If 80. he has the
means readily at hand. Supposing that he
wants rubies, he fuses with paste a small
quantity Of peroxide of manganese and n
trace of Cassius purple, which will give the
proper color, For emeralds, he employs IN
like manner oxide of iron, and for sapphires
oxide of cobalt.
.Topaz is easily formed in the crucible
by mixing with 1000 parts of paste forty
r,rta ~ uinao ,f opfimnDv and pna mart nf
Cassius purple. For manufacturing other
kin Is Of gems there are methods equally
simple. or course, zone of these imitation
precious stones has the constitu-
ton, hardness, specific gravity. or optical
properties of real ones. Accordingly, their
falseness Is readily perceived by an expert.
Inasmuch as the elements of which various
gems are composed are we'll known, syn-
thetic chemistry has attempted to repro
duce them by putting the Ingredients to-
gether and effecting Capitalization in the
laboratory. In this way large masses of
what might be termed true rubies and sap
phires are turned out artitcially. such GEM
like material having some usefulness for
industrial purposes, although lacking the
brillianoy of natures products.
For my own part l am confident that
sooner or later some, if not all. of the
stones deemed precious will be reproduced
by ~artifioe. The chemiats who have hither-
to confined their attention to taking things
apart are beginning to learn how to put
them together. All the gems are very
simple in composition and the problem il
merely to make their clements crystalline
properly. In all suoh knowledge science
has made but little progress az yet. We do
not even know for what reason one sub.
stance is transparent while another is
Opaque, though presumably there is some
relation between tho arrangement of the
molecules in the transparent BODY and the
length of the light waves which. in the case
of the transparent body. permits the latter
to pass through"