The morning news. [volume] (Savannah, Ga.) 1887-1900, 1888-07-07
ECCENTRIC JEWELS.
Some Interesting Neurological Freaks
Diamonds and Other Stones.
EL.o,,, an, NJ, VII. Tiu,ae

10 the composition OF the various KINDS Oh
diamonds among even those who enjoy a
degree of prosperity which enables them to
possess such costly Jewels. A great many
people, perhaps ma iorlty of those who
own them, know them only by their color,
their luster, or by the price they paid for
them. Nevertheless those who wear
diamonds, as we'll as those who would like
to- arc interested in anything that relates
to these precious stones.
Within five years the study of the dia-
mond by scientists has developed some of
the eccentriclties OF this most precious OF
natures formations. One of the most
extraordinary of these eccentricities was
brought out recently by an experiment at
I1iiany's great establishment in this city.
In a recent lot of diamonds purchased by
the TitIanys was q fine specimen of "round
bort" and George f. Kunz, the
mineralogist employed by the firm as
gem expert, determined to test its hardness
on the polishing wheel. Ground bort" is a
distinct form of diamond, called by the
French 'extreme durete,n aud is harder
than any other kind of diamond
known TO exist. The specimen to be eX-
perimented with had been cut into the
usual form of the brilliant, and its table"
or face, was placed on the polishing wheel.
For 100 days it was kept on the Wheel which
VfplNNh 'rOD JIlllr0 iltI IlllIuJC. IhO IjOlilO
at which the diamond came into contact
with the rotating surface was about -
inches from the axis 1t was calculated
that the diamond passed over a surface
amounting, i'll the aggregate, to 10000
miles. Notwithstanding that the pressure
placed on this diamond was gradually in
creased from 2 pounds Che usual weight
to 40 pounds, the gem refused to take
polish sufficient to give it a commercial
NH
and badly damaged the wheel, throwing
constant sciptillations in all directions.
In paper prepared by Mr. Kunz on the
subject of peculiar specimens of rough
diamonds he refers to this "hard round
bort" at is" he says, "often called the
rolled diamond hut this is a palpable mis-
homer, since the diamond cannot be rolled.
There is nothing in nature hard enough to
abrade IL except the diamond itself, and
this is never found in sufficient quantity,
Moreover, the form under consideration is
quite uncommon and so ex essivey hard
that it could never be abraded under any
natural circumstances, not even with an
entire pothOle of diamonds, a very unlikely
occurrence. 1t requires 100 days to put
slight polish on n surface five millmetcrS
square, The Koh-i-noor, with . GOO square
mllimeters of surface, was cut IN thirty
eight days of twelve hours each, while it
took 600 hours, or nearly twice as much
time, to polish five millimeters of surface
on the specimen of hard bort. This
form is made up of a multiplicity of twin
nings of cubes, or radiating agglOmerations
of cubes The roughness is evidently due
to the fact that the cube face in nearly all
diamonds is indistinct. At times, instead
of twinning, cubes have been noted that
were made up of an apparent fibrous group
ing, resembling n round ball, but really
made up of q punching of cubes Another
interesting specimen of this hard, round
bort is a piece within perfect octahedron of
crystalliz 'd diamond penetrating and pro-
jecJing above the mass, showing that the
two forms have cryStalGzed under different
conditions; also, two broken masses of the
same, both of which reveal a structure
radiating from the center of the mass. As
none of these forms of diamonds has been
observed in South Africa, as far as | can
learn after witle inquiry, it seems proba-
BILE that both the hard form and the cube
form are peculiar to Brazil
Among the Tiffany collection of Jewels
are, or were, two octahedrons and two hex
octahedruns, all white, weighing about
threc-quarters of carat each and measuring
three millimeterS in diameter These stones
contain large spots of n rich aurelan red
inclusion, perhaps red oxide of iron, and
they also contain black carbon inclusious.
which, cOntraSted with the white stone,
and the brilliant red present beautiful ap-
pearance. A diamond within diamond is
a wonderful example of this Jewels eccen-
tricity. A fine white octahedronal crystal
was recently received at Tiffany's from
which one face of the OCtahedrOn was re-
moved by chewing. After this plate was
removed an inner crystal dropped out. 1t
was probably formed simultaneously with
the larger crystal.
"A diamond known in Tiffany's as No.
"a consists of two punches of hexocta-
hedrons, forming n roseute or a remarkably
perfect six-pointed star. twelve milimeters
across and nine millimeterS thick The
color of the larger group is graylsh white.
but the smaller one is pure white"
A suite OF wonderful round diamonds
was exhibited at the international expo
sition held in Amsterdam in 1888, where
they were awarded for their size and merit
the prize for "rouud bort They were
purchased by firm in this city, and, being
offered to Tiffany, were submitted to Mr..
kunz for examinat on. 4 close inspection
showed the expert that one of the stones
was not diamond, although it had passed
all previous inspection and had taken a
prize at Amsterdam. Mr.. Kuuz was kind
enough to tell n reporter the other evening
how he came TO make this discovery. II
never trust entirely to my sight, y he said,
when testing diamonds. In this case
scratched the specimen with n cut diamond
and ii left a red mark, which proved that it
was red hematite sphere that bad been
rolled, and was evidently pseulomorph
after limonite or some other mineral dia-
mond, on was filed with air cavities. 1t
seems remarkable that this specimen.
having been viewed by a majority of the
Amsterdam dealers, examined hy the
judges and experts, and then passed through
the hands OF several old and experienced
importers OF diamonds, should have deceived
them all. so perfect was its color and
luSter that oven diamond cutter, whom in
formed of the facts in the case was net
convinced until he had tried the stone on
the wheel. This collection was of Brazilian
origin, and all were as round MS marbles.
In this form they can be used for drilling
purposes to equally good advantage with
the black amorphols carbonate, as tho in
tricate twnuiug or compomiimg destroys
the easy cleavage pr, pariy that renders or
binary crystals unit Tor this purlOse
Another curious diamond in the posses
sion of Tiffany q Co. -" Mr.. Kunz continued.
weighs I-2 carats The original weight
was 10 CaratS, four caratS having been lost
IN cutting. This stone has IS facets. of
which four Of the top AID the table, are
white, AID four are a diSliuCt black: ON the
back four facets a q white and thu Other
four and the culc are black. The stone.
which is Of Brazilian origin, was found 10
Ice exceedingly lard, and was originally an
oGtahe Iron. When fouad the entire stone
was jet a'l, and H. was cut with the in
tentlon of producing black stone. After