which
was supposed to be non-diamond-bearing. It was also agreed that a load
of ground in place should be 9.6 cubic feet, but this was afterward
increased to 10.6, as it was found that 9.6 cubic feet of yellow ground
would not make a load when broken. From the preliminary washing of
ground taken from various parts of the mine, it was estimated that the
mine would yield about 16 carats per hundred loads washed. Ward took
possession of the mine, and through contractors erected a large washing
plant capable of washing 4,000 to 5,000 loads daily. During the five
years Ward mined and washed the 5,000,000 loads to which he was
entitled. The yield was about 20 carats per 100 loads by means of the
first sortings, and possibly two or three carats more were obtained by
subsequent sorting, so that the total number of carats obtained
reached about 1,100,000. As to the price realized for these diamonds
and the cost of producing them, I have no knowledge, but one may assume
that the average value of the diamonds was about 18s. per carat, and that the cost of mining and washing did not exceed is. 6d.
per load, if it reached that figure. The first 60 feet were easily
mined, as the ground was decomposed and could be sent direct to the
washing machines from the mine. At the present time, under De Beers
management, blue ground is mined and deposited, harrowed and watered,
and then loaded and sent to the washing machines for a cost of about is. 2d. a load.
From
the year 1871, when the four mines at Kimberley and the Jagersfontein
mine were discovered, a period of twenty-one years elapsed during which
no paying diamond mine was found, although continuous prospecting was
carried on. The Premier mine was covered for an average depth of eight
feet with lime, which for the most part was diamond-bearing. The
formation of the lime seems to have been the result of the evaporation
of water highly impregnated with lime, or possibly springs existed in
the localities, whose waters were highly impregnated with carbonate of
lime, which was deposited by the evaporation of the water. Water, in
many of the lime-covered districts, is found very near the surface. On
the Wesselton estate
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