The
prices are paid to the four producers in South and Southwest Africa
every quarter and are based on the net average price realized by the
syndicate for the respective quotas during the previous three months,
less 5 per cent. The quotas were fixed as follows:
NOTES ON DIAMOND MINING IN SOUTH AFRICA.
The
following is an extract from the annual report of the Department of
Mines and Industries of the Union of South Africa in 1919:
The
continued increase in the price of diamonds, which has been most
striking, has naturally resulted in renewed activity in prospecting
and in the working of alluvial fields.
Although
the strict control now exercised over production and sale by agreement
between the principal producers steadies the market and allows of a
continual enhancement of price, it may be pointed out that high prices
have their disadvantages. In most commodities, in which supply and
demand balance each other, the sale value of the commodity can not get
away very far from the cost of production, which thus acts as a
stabilizer and insures a certain reasonable minimum below which prices
can not readily fall. In the case of diamonds the sale value of the
big producers is at present far above the cost of production. This
large margin enables a number of smaller producers whose costs are
considerably higher to work also at a profit. A slight contraction of
the market then becomes disastrous to these producers; and at all times
the knowledge that the large producers can, if need be, place diamonds
on the market at a much lower price is an element of danger. The
security rests, of course, in the monopoly of control, and as long as
this is maintained the position is safe. A further danger lies,
however, in the possibility of the discovery of important new mines.
With such great activity in prospecting as is now prevalent, such a
discovery is by no means to be looked upon as impossible. It is
unlikely that all the large diamond pipes already known are the only
ones that exist. If other large and valuable pipes are discovered, they
will be a disturbing element in the market until they also come within
the monopoly of control.
GOLD COAST COLONY.
The
discovery of a new diamond field in the Gold Coast Colony by the
director of the Gold Coast Geological Survey, Mr. Kitson, is reported
in Commerce Reports for December 15, 1919, which quotes a report
published in the Gold Coast Government Gazette. The diamonds vary
greatly in size. The largest found are about the size of a split pea;
large numbers of them range in size from a large pinhead to a grain of
millet; and many are still smaller. Of one lot of 175 stones the weight
of the largest is about a carat; of the average stones of medium size
28 weigh one carat; and of the next grade there are 36 to the carat.
The whole 175 stones weigh 4-13/32 carats. Many of the diamonds are
beautifully perfect crystals, colorless and transparent. The commonest
forms are the octahedron and the rhombic dodecahedron. A few are of
pale-yellow, blue, green, gray, and brown tints; others are colorless,
but with small dark inclusions. Cleavage plates of octahedra occur in
fair numbers, indicating that the original crystals were much larger
than any of those found. The Board of Trade Journal states that their
value
