Mower County transcript., 1890-07-30
MANUFACTURED GEMS.
sapphires and Rubles Not Distlngulshabll
from Real Stones.

sapphires and Kubies Not Distinguishablo
from Real Stones.
In the long gallery on tho top floor OF
the museum at Sevres Is modest-look.
Ing glass case about two feet square,
divided into compartments, each con-
taining chemicaL There is q blue sub
stance, red substance and some dirty
white crystals. In tho last two COM
partments are two saucers containing
small colored stones.
These stones are genuine sapphires
and rubies undistinguishable from the
real stones by any chemical test,
and only differing from them in the
fact that they have been manufact-
ured not found; or, to Use q
technical expression. they have been
produced alphabetically. The other con-
tents of the case are the substances
used in making these precious stones.
The rubies, of which there are about q
dozen, are small. certainly not larger
than Q grain of wheat, and very uniform
in size. They are in the shape of regu-
lar rhomboid crystals, that is, four sided
but not rectangular. and apparently
flawless; but as they are rough and un-
cut it is not easy to detect flaws. The
coloring, as is the case with all uncut
stones, is somewhat dull, and might be
described as slaty lake.
The sapphires are much larger and
vary in size, the smallest being about
as large as pea and the largest rather
bigger than hazel nut, but in crystal
ization they are very inferior to the
rubies. They approach, it is true, the
rhomboid form, but very roughly and
with pronounced Irregularities. One
stone, for instance, has a body almost
square with a spur projecting from it,
the whole being almost like saucepan
in shape.
All the larger stones show distinct
lines of cleverage, so that they would
lose large part of their weight in cut
ting. The sapphires are not of the dark
blue type, but have tendency to pur'
pie, being almost exactly the shade OF
Ceylon stones. The color would per
haps be best described as blue with a
reddish sheen. There is strong fam
lily likeness between the two classes of
stone, and one could almost guess from
their mere appearance that they had
been produced by similar processes. lr
fact, the base of both rubies and sap
phires is the same, and they differ only
in coloring matter.
The base is silicate of alumina, or in
common language, q combination o!
aluminium and flint. In order to pro
duce rubies the silicate is mixed with
bichromate of potash, and the whole is
kept at a certain temperature for several
hours until the fusion is complete. Fol-
sapphires, cupric sulphate or ,sulphat tt
of copper is substituted for the bich
romate, but otherwise the process OF
manufacture is the same. The great diff
Guilty is to obtain regularity of crystali
zation.
The rubies tend to break up into to<
small pieces, while the sapphires art
rough and full of flaws Apart from thi.
the stones are not limitations, but re-
productions of the natural jewels. In
France it is illegal to sell them as
rubies and sapphires without stating
that they are artificial. But even if the
sale were illegal it is not likely that they
would come into the market in sufficient
quantities to depreciate the natural
stones, owing to the difficulties in
production yet to be overcome.
er's Weekly.