SOUTH AFRICAN DIAMONDS
large
scale and yield enormous profits. It is stated that the output from
1867 to 1897 was over 33,000,000 carats, or about 7-1/2 tons,
valued after cutting at $450,000,000. Quite recently another diamond
field has been opened in TransÂvaal. The largest mine is the Premier.
At this time the South African diamond fields yield about 98 per cent
of the total output of the world.
In
1883, as the first shafts began to burrow down into the mines at
Kimberley, the diamond trade was expanding so swiftly that the mines
could barely keep up with it. Wealth was diffusing downward to improve
the lot of the common man, and diamonds for the engagement rings, once
the prerogative of kings, were now available to any laborer who could
save his money. Brazil's peak of producÂtion had never passed 600,000
carats a year; about 100,000 was its average. But South Africa was soon
able to mine a million carats annually, and more and more.
The
"River Diggings" at first was supposed to be alluvial in its origin
like the river gravels; but it was soon discovered that below the red
surface soil diamonds also were found in a layer of yellowish clay
about fifty feet thick known as "yellow ground". Below this again was a
hard bluish-green rock which has become famous under the name "blue
ground". The yellow ground is merely decomposed blue ground.
It
was soon found that each mine was in reality a huge vertical crater
descending to an unknown depth. At first each claim was an independent
pit thirty-one feet square sunk into the blue ground.
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