The Greeley tribune., 1910-06-09
THE BLACK DIAMOND
It Is Ono of the Curiosities of the
Mineral Kingdom.
!. PUZZLE TO SCIENTISTS.
Mature Has In Some Peculiar Way
Produced This Rare Form Of Carbon
and Then Thrown Away the Secret
Of the Proesss-Found Only In Brazil


Of the Proesss-Found Only In Brazil.
The term ''black dia mODds' Is sOmc
times jokingly applied to ordinary coa
which we burn III our furnaces. but
the real "back diamonds of com
nierce are among the mos, uiii,lur MN
eral products of the world. and the.
serve purpose in the industrial worll
that makes them of great value The
black diamonds are pure carbon aud
yet In no outward appearance resem
BILE the diamonds which we are uccus
toned to wear us ornaments. They
are slightly harder than the crystal or
gem diamonds and. in fact. about the
hardest substance known.
| Black diamonds. or carbons. are
among the greatest curiosities of the
mineral kingdom. They are without
crystalline form and are found In ir
regular pieces. ranging in size from
half carat up to three. four and five
hundred carats They are dark gray.
black or brownish in color and opaque
The real diamond of the jewelry trade
| 10 utSO pui' Val pou, Out
and 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
black diamonds is that they are found
only in one locality in the world. They
come from very small section of Bra
| nil hnv in,
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 u black diamond? No
one would care to wear one of these
diamonds which resembles u piece of
coal more than a real diamond. and SO
far no one has popularized the black
gems as the black pearl has been.
Nevertheless the black diamonds serve
most important and useful function
in the Industrial world.
This pure black carbon is not only
, harder than the real diamond. but
, toughs12apd not 20 brittle as the gem.
Consequently 1t IL 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. OF
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
tached to tubing. Armed with these
black diamond teeth. the drills push
their way down under severe pressure
10 Il depth of five and six Thousand
feet cutting through the hardest kind
of rock. Some black diamonds are
much harder than others. and there Is
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. and the own
ers of the mines in Brazil where the,
are gathered are making good thing
out OF their monopoly. There is no
1nown 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 It was i'm
possible to make borings.
When the carbon was first tntroduc'
ed in our industries 1t was used in
diamond saws for cutting stones, mar
Bile and similar substances. Then the
price advanced SO that the carbon WAS
found too costly for such use. and bort
was substituted for stone cutting Bort
is really an imperfect crystal or gem
diamond, but It is too brittle for use
in drills. Consequently bort has tax
en- the place of black diamonds fof
stone cutting. and the latter have been
restricted almost entirely to diamond
drilling purposes.
The average size of black dlamouds
used in the drills ranges from two to
tlve carats but the larger specimens
give much better results. They cost
more. but they last longer, ConSe-
quently there is IL greater demand tor
the larger pieces of pure carbon, ana
the price is sometimes run up to pre-
MUM figures for unusual specimens
The fear that the supply of black
diamonds may some day give out and
puralyze the diamond drilling industry
has stimulated prospectors to syste-
matte search for new deposits. but 50
far they have not been successful. ON
the other hand scientists have been
making a close study OF the chemical
conditions which have produced the
black diamonds but their manufacture