Wauwatosa news. [volume] (Wauwatosa, Wis.) 1900-1948, 1910-07-15

"a ID oily OF the worlds supply OF
# the black diamond, while the
M United States is its largest
market 1t is found in La
Chapada and Lavras districts
of the province of Bahia, Brazil,
where IL is mined from river beds and
other alluvium. The miners sell their
find to agents of exporting firms in
the city of Bahia. II is calculated that
this port ships annually about $4,000.
600 to S4,600,000 worth of black dia,
monds, and, with the adoption of
modern methods and machinery in
place of the extremely primitive ones
formerly employed, the industry will
be. tremendously stimulated, About
twenty-five years ago a stone of 100
carats was fouEd, followed by one of
LOO carats, and In 1895 a gigantic
stone of S,07S carats, or els grams,
which was purchased by New York
house fer s32,00 and broken up into
| pieces of suitable size for diamond
drills. AT present prices this stone
would be worth about $685., 600 Dur
| Ing the past ten years stones of 400
| TO 500 carats have been discovered,
while they are frequently found weigh
ing from 100 to 200 carats.
Previous to 1870 carbonate was
| practically valueless From 1870 to
| 1872 it was employed as an abrasive
/ for cutting and polishing the white
| gems, and thousands of carats were
/ a -. ~
ed to powder for this purpose. A few
| years later, when carbonate was EN-
ployed in diamond drilling, it sold at
| from 81 to 81 carat. Between 1895
and the present the market value has
| fuctuated between $25 and $S5 a carat,
this high price being caused by the
decline in the supply of carbonate in
the past ten years, while the demand
has increased. In connection with the
| subject of black diamond consumption
In drilling, 1t is interesting TO remark
that in digging the drill hole at Ryb-
mix iParuschowitzj, Upper Silesia,
which attained depth of nearly 1000
feet. upward of $4,000 worth of car.
bonado was used
The conditions are entirely differ
| ent from those of Africa. The gravel.
! sand, and other material containing
! diamonds lie in or near the beds of
streams and rivers, and have been
washed down by erosion from high
'chapadas' or plateaus, which are
| probably the original matrix In which
! Brazilian diamonds were formed. AS
is natural, gold and variety of other
substances, such as itacolumnite,
olivine, limestone, hematite, granite,
gneiss, and clay are associated with
the diamonds. The diamond bearing
material OF Brazil consists of a con
glomerate, sometimes interbedded with
lard yellow sandstone, which is wash
ed down through erosion by rivers. or
in some cases. may be badly decom-
posed and rotten rock Fossils are
generally lacking. The deposits often
consist of schists and schistose clay,
diamond-bearing clays, reddish earth.
granite and gneissic formations, and
pebbles of various sorts.
The states of the republic which
have yielded diamonds are Minas
Geraes, Parana, Bahia, Goyaz, and
Matte Crosse. II is in the first named
that Diamantina, celebrated for the
rich diamond mines I'm it's vicinity, is
situated. The city is well built and
lies at the headwaters of the Jequitin.
honha, or Diamond, river, a stream
$50 miles long, which empties into the
,,P
Diamantina is the peak of Mount
Itambe, $500 feet, in the Sierra Espin.
AGO Range. The mines are situated
north OF Rio de Janeiro, 500 kilo-
meters, or 497 miles, north Of Ouro
Preto, the capital of Minas Geraes.
The territory in which they are stu.
ated forms a vast ellipse, 50 kilo-
meters, or 80 miles, by 40 kiiometers
or Is miles, in a plateau 900 to 1900
meters 1920 to 1897 feetJ, anntain-
ing a number Of valleys cut by the
equintinhOnha and its left tributaries,
/ Ribeirao do Inferno, Rio Caethe, etc,
and also by the Sac Francisco's af-
fuents which flow TO the northwes in
a very different basin.
Although diamond mining has been
more extensively and systematically
pursued in the states Of Minas Geraes
and Bahia than elsewhere in Brazil
Matte Crosse, Goyaz, and Parana have
yielded sufficient results to Justify the
belief that their future as centers Of
diamond production will be prosper
Gus.
The primitive methods + mining
| employed In Brazil until recent years
have, nevertheless, abundantly re-
vealed the natural productiveness Of
the Brazilian diamantiferous deposits
Two native methods are sin very
largely in Use, according to the local