Evening star. [volume] (Washington, D.C.) 1854-1972, 1905-02-07
icers Of the House,
BLACK DIAMONDS OF BRAZIL.
Digging the Precious Stones on the
Banks Of the Sac Jose River.


From the World Wide Magazine.
The black diamond is an important article
of commerce, not because it is destined to
enibellish the hand of feminine grace, but
because of the fact that it has been widely
applied in industry where it is almost as
valuable as its white fellow. The home of
the black diamond is Brazil, the classical
land of the diamond, the richest beds of
the mineral having been found in the
province of Bahia and on the banks and in
the bed of the Sac Jose river. The stone,
which is perfectly opaque, is not beautiful,
and If the magical word diamond had never
been applied to the substance there Is no
doubt that to this day the black diamond
would be thing unknown. However, the
favor which this mineral enjoys is of very
recent date, for twenty years ago it's prop
critics were unknown and the trade in the
ston. was practically nothing.
The constantly increasing perfection of
boring instruments brought out the value
of the black diamond, the use of diamond
point drills now having become so general
that the price of the mineral has in con-
sequence rapidly increased. Today the dia-
mond has become of prime necessity in
working tempered metals, saving OF
marbles. piercing of tunnels and galleries
and in mines. At the time of the Inaugural
ton of the Laboratory of Arts and Trades,
July 1, 1903. circular saw, provided with
diamond points, produced surprising re.
suits, cutting into thin slices the hardest
of materials On the banks of the Sac
Jose we find traces OF the first exploitation
of the mines by the natives, the Garimpe-
ros. The black diamond, however, having
no commercial value, did not attract these
people, and they were apparently ignorant
of the real character of the mineral. From
the report of an engineer who explored the
region in 1858 we learn that one day the
diamond diggers discovered black stone
in Sac Jose. They took the stone to one of
hnf h1rf,. 70 tic 0fr1rQ
by attempting to crack it. All their efforts
were fruitless, the stone resisting the most
powerful hammers, and after a time it was
thrown back into he river. The stone
weighed about 10000 karats, and at the
present price of $40 karat represents a
loss of $4,000
The exploitation of the Brazilian diamond
mines by the Garimperos, it is unnecessary
to say. was not scientific. The crevices of
the rocks are explored with the hand, the
gravel being taken away in little barrels
which are carried the head. Attempts
have been made to lessen the time of the
work by diving for the mineral. but the
violence of the stream is such during the
rainy season that this plan has been but
little adopted. The only method which will
produce results and the one which will
shortly be put in operation is that of drain
ing. Dams will be erected 300 feet apart
and centrifugal pumps will be installed Tor
the purpose of drawing off the water. The
results of the work cannot be a question
of doubt, judging from the past perform
anceS of these diamond mines.
The question naturally arises, Why have
the diamonds been found in the Sac Jose?
The answer to this is not difficult and is
given when we state that the original rock
which formerly occupied the high plateau
has been gradually disintegrated the
debris of the rock being carried by rains
into the Sac Jose. Because of their dem
sity the black and white diamonds were
concealed under the sand. together with the
mineral accessories which surround them
and which are the indications of the
precious stones. Thus, in the course of
years, these. beds have been formed, beds
the richness of which is incalculable.