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APPENDIX IX
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327
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loads
hauled during the year 1902 is given at 8000 weekly. The Leicester
property consists of two pipes adjoining one another. One is a very
much larger pipe than the one above, but it contains no diamonds.
Newlands Mine. — No work was done during the year 1902.
Other Mines. —
There are several so-called mines or prospects which have been before
the public at various times, but the amount of development work does
not amount to very much, and in the Inspector of Claims Report he
classes them as "abandoned mines, unleased."
Professor Bonney mentions the eclogites of the Kimberley or Barkly Districts.
Large
boulders of this rock occur in all the mines at Kimberley, and after
reading Professor Bonney's monograph I caused a few truck loads of the
rock to be gathered from the waste heaps and had them crushed and
washed, but no diamonds were found. Quite a number of specimens of
diamonds and garnets cemented together have been found, but in most
specimens which have come under my observation it is difficult to
determine whether the diamond has grown into the garnet or the garnet
into the diamond. A diamond was recently (January 9, 1904) found in (De
Beers) Premier Mine which has a small garnet embedded in it. The
diamond weighs 114 carats, and the garnet is estimated to weigh about
half a carat. It appears to fill the hole in which it is embedded. The
diamond is of cubic crystallization, with nearly half of the cube
wanting. The part of the diamond in which the garnet is buried has
numerous depressions similar to the one containing the garnet, and one
is led to think that these depressions were also filled with small
garnets, or in other words, the diamond crystallized upon a nest of
garnets. The value of the stone, .£40, is rather too great for a
cabinet specimen. It is of a peculiar plumbago color and
semi-transparent. All of the diamonds crystallized in cubic form which
have been found of late in Premier Mine are of this peculiar color.
Professor
Lewis says: " Kimberley diamonds have been found sometimes to have
optical anomalies due to strain. . . . Fizsan thought this strain to
have been caused by the unequal distribution of heat during cooling,
but Jaunettaz [Bull. Soc. Min. de France, II, 1879, p. 124) holds that the strain is due to compressed gas in the interior of the crystal."
Professor
Lewis says : " Perhaps the most interesting chemical observation
concerning the ' blue ground' was that made by Sir H. E. Roscoe. He
found that on treating it with hot water an aromatic hydrocarbon could
be extracted. By digesting the ' blue ground' with ether and
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