The Helena independent. [volume] (Helena, Mont.) 1875-1943, 1893-02-20
CONTRIBUTING GEMS.
Hsw Some Gems Are Artificiallv Prepared
by tho Man ufacturers.

Hsw Some Gems Are Artificiallv Prepared
by the manufacturer
1.-THE finest imitation diamonds are made
out of rock crystal" said q Washington
dealer in precious stones. 1.-THE basis Of
the most successful counterfeits of all kinds
of gems is a pure, very dense and highly
transparent sort of glass, which is termed
paste in the trade. For false diamonds
facets. while fos initiating other stones.
such as rubiss, emeralds, sapphirss, etc,
metallic oxides are mixed with 1t.
I manufacturing glass for sueh pur-
poses the processes employed have to be
conducted with the utmost nicely. For
sary silica is obtained from ordinary white
quartz, while common window panes are
produced from sea sand to a large
extent; but in this case. rock crys-
tai is substituted. composing about
SO per cent of the ingredients of tho paste.
ate OF soda n due proportions of caloined
borax. saltpstsr and red lead. AL of these
things are reduced to the finest powder.
mixed, fused together by heat in crucible
and COOLED slowly.
The density, transparency and beauty OF
the plate' depend upon the care taken in
these processes. Thus made. it 10 all ready
to BE- cut up into diamonds n prepared
for market. 1t may be, however. that the
manufacturer desires to produce counterfeit
gems OF other sorts. II 80. he has the means
readily at hand. ~Supposing that he wants
rubies, he fuses with paste q small quantity
of peroxide OF Manganese and 4 trace Of
Cassius purple, which will give the proper
color. For emeralds, he mploys in like
manner, oxide of iron, and for sspphires
oxide of cobalt.
Topaz 10 easily formed in the crucibla
by mixing with 1000 parts Of paste forty
parts of glass of antimony and one part
of Cassius purple. For manufacturin
other kinds Of gems there are methods
equally simple. OF course none of these
imitation precious stones has the chemice
constitution, hardness, specific gravity. o.
optical properties of real stones. Accord
ingly. their f%alseness Is readily perceived
by 81 expert. lnasmuch as the elements o
which various gems are composed are wei
known. SYNTHETIC chemistry has attempted
TO reproduce them by putting the ing Z
dients together and erfscting capitalization
in the laboratory. In this way large M asse
of what might be- termed hue ruby ans
sapphire arc turned out atti6cially, suol
ReM-liks material having some usefulness
for industrial purposes. although !aokin,
the brllliancy OF natures products.
"For my own part, l a1n confident tina
sooner or later some. If not all, of TIA,
stones deemed precious will be reproduced
by attltce. The hemlst who have hith.
erto confined their attention to takin,
things Al art are beginning to learn how t,
put them together. All the gems are yer,
simple In composition and the problem i
merely to make their elements crystsliz
properly. In ali such knowledge eeienc
has made but little progisss as yet. W
do not even know for what reason one sub
stance ID transparent while another j
Opaque, though presumably the is som
ielation between the arrangement of til
molecules in the transparent body and th
length OF the light waves. which. in tn
case OF the transparent BODY, permits tn
latter to psss Observation-Disclosures Star
Lace curtains. full size. for 81 per pair at In
Pes Hive this week.