The Washington herald., 1908-01-05

The scientific sensation Of the moment
in Paris is the fact that Prof. Frederick
Rordas. of the College of France, has
succeeded, after long and patient expert
ments in producing precious stones by ex-
posing the coarse ordinary form Of
crystaliized alumina. known as corundum
or adamantine spar, to the action Of
radium
The possibility that this process may
be used industrially for the production
Of certain kinds Of precious stones at a
cost which will seriously modify the
present market values of the natural
gems, invests the subject with much in
terest. All these gems are in compost
tion crystallized alumina, but through
long exposure 10 varying conditions Of
heat ard pressure during the slow cool
ing and development of the earth's sur
face they have assumed different coIors,
to which the names Of ruby. amethyst.
&c. have been given. The discovery Of
radium revealed the active agent through
which various changes in certain sub
stances. which had hitherto been Of slow
progress, might be intensified and ac-
complished in a comparatively brief time,
says Harpers Weekly.
The present discovery Of Prof Bordas
was suggested by the fact that the min
ute glass tubes in which radium is con-
fined and kept for scientific use take on
gradually a beautiful azure color resem-
bling the sapphire This was attributed
by Prof. Berthelot TO the presence Of
traces of manganese in the glass, which
the marvellous pTOjectiie power Of the
Tadium reveals and reviyes with varying
grades and tints of cOlOration. Prof.
Bordas therefore placed crystallized cor
undum OF several tints in contact with
minute tubes OF Tadium laid them away
in a dark place not subject to changes Of
temperature. and found after a lapse OF
several weeks that the white corundum
had become yellow ike the topaz, the
blue crystals had become green like the
emerald, and the violet had turned TO
blue Ike the sapphire.
Scientists Theory OverthrOwn.
This has Overthrown the theory held
hitherto by scientists that each 0f.these
precious stones had its own special
colcriDg oxide. and that these several
oxides-green. blue, red. or yellow
have no definite relation TO each other
Prof. Bordas took his newly-created
gems 10 a leading lapIdary jeweler.
from whom he had purchased the CO.
rundum crystals, who identified and
tested them, and found that they had
been converted into a topaz, ruby.
and a sapphire. which fulfilled all the
tests and requirements of natural
stones.
He then obtained from the same
jeweller new series OF eorGndum
crystals In pairs, each pair OF an ez-
actly similar color. One stone of each
pair was exposed for a month TO the
action of radium, the other retained
| for comparison, and the result OF this
| second experiment was the same as
before. The light reddish corundum.
valued in commerce at about so cents
per carat, had been converted into a
ruby valued at 500 10 $3.50 per carat
The dark red corundum became a deep
brilliant violet, the violet amethyst had
become sapphire, and the blush CO.
rundum a topaz.
The possible effect OF this discovery
/ upon the trade in jewelry and precious
stones can be readily inferred. Radium
| is as yet one of the rarest and most
| precious substances known 10 science,
| but the duration of its power is prac-
tically unlimited. and since one milli-
gram (0.0154 grain) of radium is suf-
| iieient TO convert several cOrundum
! crystals into precious stones within the
| space Of a month, and since this process
may be repeated indefinitely with the
same speck OF radium, il is naturally.
/ though, perhaps, prematuTely. assumed
/ that this latest discovery may have an
/ important industrial value and lead TO
/ serious notifications in the commercial
1 prices Of certain precious stones, Prof.
/ BOrdas, however, regards his discovery
as a mere laboratory experiment, and
disclaims any intention to secure for it
! a commercial value