Bryan daily eagle and pilot. [volume] (Bryan, Tex.) 1909-1918, 1910-02-02
THE BLACK: DIAMOND
Il Is One Of the Curiositles OF the
Mineral Kingdom.
A PUZZLE TO SCIENTISTS.
Mature Has In Some Peculiar Way
Produced This Rare Form Of Carbon
and Then Thrown Away the Secret
Of the Proeess-Found Only In Brazil.

times jokingly applied TO ordinary coal
which we burn IN our furnaces, but
the real BLACK diamonds" OF com.
merce are among the most unique min
sral products OF the world. and they
serve n purpose In the industrial world
that makes them Of great value. The
black diamonds are pure carbon and
yet IN no outward appearance resem'
BILE the diamonds which We are accus-
toned to wear as ornaments. They
nre slightly harder than the crystal or
gem diamonds and. In fact. about the
hardest substance known.
Black diamonds, or cnrbons, are
among the greatest curiosities OF the
mineral kingdom. They are without
crystalline form and are found In IT.
regular pieces, ranging IN size from
half carat up TO three, four and Ave
hundred carats. They are dark gray.
black or brownish In color and opaque.
The real diamond Of the jewelry trade
Is also pure carbon. but translucent
ard crystalline In form. Two objects
so alike In composition could not be
found so opposite in appearance as
these two forms Of carbon.
Another peculiar thing about the
blnck diamonds Is that they are found
only IN one locality In the world. They
come from n very small section OF Bra
iii moi more than 225 miles square n
area. Outside OF this limited territory
no pure black diamonds have ever
been found
What peculiar freak Of nature caus
ed the deposition Of the black dia
monds In this section OF the world and
nowhere else Is one Of the mysteries
which science has failed TO explain.
None OF them has been found In the
great Kimberley diamond regions,
where the crystal form Of diamonds
have for so long been mined
The whole origin OF the black dia-
mond Is, therefore, scientific enigma.
Naturally the question is raised. "Of
what use is black diamonds" No
one would care 10 wear one OF these
diamonds. which resembles piece OF
coal more than u real diamond, and so
far no one has popularized the black
gems as the black pearl has been.
Nevertheless the black diamonds serve
a most important and useful function
In the Industrial world.
This pure black carbon Is not only
harder than the real diamond. but
tougher and not so brittle as the gem.
Consequently Il Is OF great value for
many mechanical purposes and partic-
ularly for boring with diamond drills.
In diamond drilling the tips OF the
drills are studded with carbon. or
black diamonds. and when the bores
ARE deep the pressure is so great that
the gem diamonds would be crushed In
the process. But the carbon resists
this continued pressure and slowly
eats down into the rocks.
In diamond drill work the carbon Is
set In circular pieces OF soft steel or
iron. called bits. and these bits are at
tachcd 10 tubing Armed with these
black diamond teeth. the drills push
their way down under severe pressure
TO depth OF i've and six thousand
feet. cutting through the hardest kind
OF rock Some black diamonds are
much harder than others, and there IL
no way to determine by the color the
difference In the degree Of toughness.
Black diamonds or pure carbon are
not By any means cheap. aud the own
ers OF the mines In Brazil where they
are gathered are making a good thing
out Of their monopoly. There is no
known substance that can take the
place of carbon In drills In boring for
gold. silver copper and other mineral
deposits Before the black diamonds
Of Brazil were discovered II was i'm
possible to make borings.
When the carbon was nrst introduc-
cd In our industries II was used In
diamond saws for cutting stones, mar
bic aud similar substances. Then the
price advanced 50 that the carbon was
found too costly for such use. and bort
was substituted Tor stone cutting. Bort
is really an imperfect crystal or gem
diamond. but II Is too brittle for use
In drills. Consequently bort has tax
en- the place Of black diamonds for
stone cutting. and the latter have been
restricted almost entirely 10 diamond
drilling purposes.
The average size Of black diamonds
used In the drills ranges from two to
i've carats, but the larger specimens
| give much better results. They cost
more. but they last longer. Conse-
quently there is a greater demand for
the larger pieces Of pure carbon, and
the price T. sometimes run up 20 pre-
MUM figures for unusual specimens.
The fear that the supply OF black
diamonds may some day give out and
\ paralyze the diamond drilling industry
has stimulated prospectors TO syste'
matte scarrh for new deposits, but SO
far they have not been successful. On
the other hand, scientists have beer
making a lose study Of the chemical
conditions which have produced ths
black diamonds, but their manufacture
Is apparently about as difficult as tbs
making OF the gem diamonds. II Il
possible under certain conditions q
make either. but not In sizes suiiicien
to be Of any commercial value. Ma
ture In some peculiar way has mad
these rare products aud then throwI
the secret OF the process away. IL an
man can ever unlock or end that Sc
=. - - ..,,.a 1, ,,aDtn On tho dia