The sun. [volume] (New York [N.Y.]) 1833-1916, 1903-09-20
AS TO COLORING DIAMONDS.

AS TO COLORING DIAMONDS.
Mr.. Kunz. the Gem Expert, Has Grave
Doubts OF a Chicago Announcement.
| A telegram from Chicago, recently printed
in The Sun, quoted W. G. Fuchs as saying
that he had discovered a process by which
a diamond may be changed to any color
desired. His process involved the use OF
the X-ray
George Frederick Kunz Of Tiffany's. one
| Of the leading authorities In this country
ON diamonds, expressed himself yesterday
az soeptical concerning at least the COM
mercial value Of Mr. Fuchs's discovery.
Attempts at bleaching diamonds have
been made, said Mr.. Kunz, from the time
of Benvenuto Cellini down to the present
day. Cellini has related how in 1854 he
! changed the coloring Of diamond by
| applying a wash, or solution, to the back.
| and he also relates how he actually increased
the market value Of certain diamond by
this process and duly pocketed the proceeds
of the transaction.
an 1891 Cellini's process, somewhat i'm
proved upon, was applied by certain un-
scrupulous dealers In this country and in
Europe, and a good many Of these doc
tored diamonds were put upon the market.
| The process in this instance consisted OF
staining not only the back but the entire
surface of the diamond with an aniline
solution.
@This led to the manufacture of device
| for the cleaning of the diamonds thus
stained. the device simply consisting Of a
convenient appliance for boiling the stones
In acid or alcohol. In this way the false
covering was quickly removed.
| "Some twelve or thirteen years ago tho
coloring Of diamonds was accomplished by
| putting them in a vacuum and by the use
Of the Crookes tube The diamonds turned
first brown and then black. but they lost
their lustre. and, furthermore, this changed
color was not maintained.
1T could he removed by chemical proc
ess and by mere abrasions as well. Some
of Lady Crookes's diamonds were subjected
| to the process and had to be repolished.
| snow might it not be that the diamonds
which Mr. Fuchs has subjected to the bonn
bardment Of Roentgen rays were merely
stained as to their surface by particles Of the
coloring matter of the substances through
which the rays passed? Probably there
! NOuu D6 utPOSllStl vi tIo VI 0iiC
diamonds a graphite form Of carbon-that
or cliitonite, which is twice rs hard AZ
graphite and is found in meteoric stones.
1T il the present theory, and l know
OF nothing and have heard Of nothing tend
ing to upset it, that the diamond Is abso-
lutely impenetrable by coloring matter or
solutions of any kind. If that is true then the
coloring matter projected by the Roentgen
! til III v>.Nt
penetrate the diamond and amounted to
a mere surface stain.
Such a stain would not be permanent,
should Judge think it would be sus-
ceptibe of chemical obiteration and it
also probably would give way under abra-
sion
NO do not think Mr. Fuchss discovery
I will have any effect on the diamond trade.
/ think may assure the owners of fine blue.
white, brown, yellow, green or black dl-
almonds that the integral value of their gems
will remain unchanged-that they are just
at any time in the history of the world, not
withstanding Mr.. Fuchss coloring devices
As to his ability by reversing the Roent-
gen process to extract the coloring matter
from diamond, leaving them pure white
why, that is feat which should want to
see with my own eyes before | studied 1t
with the view to making comments on it.
Nature herself is guilty of some queer
freaks in the coloring of diamonds. In one
instance of which know she seems to have
duplicated the processes OF artificial color
| ing that have been in use and at the same
time to have demonstrated the futility of
attempting to penetrate the diamond itself
, by any of these external processes.
-Ths was in the case of black diamond
which we sold to Siamese prince about
twenty years ago When the diamond was
| cut it was done in such a manner as to ma Ike
| thn form of "A thA allrfarp. and the
cross came out very clear pure white.
"The cross therefore stood out sharply
defined in the dark background of the
diamonds original colors. This was simply
because in cutting the diamond the surface
coloring was removed, as / believe 1t always
will be if diamonds colored by externa
process are subjected to polishing or tc
chemical treatment.
The brown diamonds in King Edwards
crown are very fine gems of their kind
The red blue and green diamonds are the
most valuable of all because they are very
rare in perfect condition.
THE pure whites come next in value
and after them the fine browns. Fine
brown diamonds are more valuable than
that Is, diamonds OF dark, smoky color
are, many OF them, very beautiful and some
people prize them highly, but. all other
things being equal they are the cheapes,
diamonds OF all.
"The price Of diamonds generally ha,
gone up about 40 or SO per cent. within the
past four or five years From so to so pei
cent. in the weight of the diamond il nov
lost in the cutting, as compared with about
} 40 per cent In the middle Of the last century
This is because there is more demand foI
beauty in cutting than there was. The
difference in this respect OF beauty ia yer,
marked when you compare the diamonds
OF recent cutting with the heavier, clumsier
} stones our ancestors wore"
PEDLERS FOLLOWED kOSSUTH
' They Were the First Of Their TT ado Seer
Us, Some Meafaen CAflea