Diamonds are mostly found in a hard, bluish-green rock which has to be
blasted, the safest time for doing this being the noon or midnight hour.
The noise of it sounds like an enemy bombarding the camp. We stood on
the edge of the mine and saw a solitary man down below, who looked as
big as a rabbit, light a fuse and then run from it for his life, when,
with a report like a thousand cannons, the earth rose two hundred feet
in the air and then fell to ground again, probably dropping a Koh-i-noor
on a neighbouring claim.
There are somewhat poorer and smaller mines at Dutortspan, Bulfontein,
and old de Boers, all comprised within a radius of three and a half
miles, and the cab-carts plying for hire in the streets have no lack of
custom in carrying people from mine to mine.
Most of the property in the mines is now owned by companies, individual
claim-holders finding that it paid them better to consolidate than
struggle with the immense working expenses of a single claim, surrounded
by blocks owned by wealthy companies. When the companies first formed,
there was some wild speculation with the stock, and several fortunes
were made and lost in a few days by amateur stock speculators. We were
invited to inspect the washing-ground of one of the large companies, and
very interesting we found it. The blue ground is taken as it comes up
from the mine to a plot of ground rented for the purpose, called a
depositing floor, and, after being dumped down in heaps, is spread out
on the ground in large, coarse lumps, just as it leaves the pick and
shovel of the miner. Water is then liberally poured over it and it is
left for two or three days to the action of the atmosphere; at the end
of that time it loses its rock-like appearance and shows itself to be a
conglomerate of pebbles, ironstone, and carbon.
It is then thrown against coarse sieves to separate the larger stones,
which are flung aside, and is afterward taken to the washing-machine.
This consists of a circular iron tub, rather shallow and some ten or
twelve feet in diameter, in which are fixed from the centre six or eight
rakes, with long teeth six inches apart, which are kept perpetually
revolving by a small steam-engine, or by a whim worked by horses or
mules.
Water is kept flowing into the tub through one opening, as the
diamondiferous soil is worked in through another. The revolution of the
rakes causes a thorough disintegration of the stuff, the lighter portion
of which is forced over the upper edge, carried away by the engine, and
thrown on the refuse heap. After sixty or eighty loads have been passed
through the machine, the rakes are lifted up and the contents of the box
carefully taken out. It will be at once understood that only the
heaviest portions of the precious soil, and therefore the diamonds, if
there are any, have been left in the machine, the lighter parts having
been washed over the upper edge of the box.
When taken out, the residue, which consists of nothing but heavy
ironstone and carbon in a pure state and crystals of various hues, is
carefully sifted through sieves of different degrees of fineness,
sometimes placed one under the other in a cradle and thoroughly rocked.
Then, when every trace of foreign matter has been carefully removed, a
dextrous turn of the hand, as the sieve with its contents is held in a
tub of water, brings the diamonds, garnets, and the heavier lumps of
ironstone into a little heap in the very centre, so that when the sieve
is reversed on the common pine sorting-table they lie together. The
white, alum-like appearance of the rough diamond contrasts strongly with
the rich-hued garnets, with which the surrounding blackness of carbon
and ironstone is studded. It is only by practice that one is enabled to
tell at sight what _is_ a diamond; the sieve appeared to be full of
them, but we were told they were only crystals, which could easily be
detected from diamonds by taking one between the teeth; the diamond
resists their action, but the crystal crumbles away. Thousands upon
thousands of garnets roost exquisite in colour are found in every
sieveful, but they are thrown aside contemptuously, being almost
valueless.
We were allowed the fascinating pleasure of sorting over a sieveful of
the pebbly-like residuum of the washing-box, and I can give no idea of
the feeling of excitement that came over us as we pored over the table,
each armed with a triangular piece of zinc for raking over the stones.
We found several diamonds, and felt like breaking the tenth commandment
as they were calmly pocketed by the manager of the "floor," but were
each somewhat consoled by the present of a small diamond as a souvenir
of the day's wash-up.
No one would believe from the appearance of a rough diamond, looking
like nothing so much as a piece of alum, that it could ever be cut into
a beautiful, fiery gem.
Of course the expenses of a company owning a block of claims are
enormous, and a large number of stones have to be found before the
margin for a dividend arrives. From the opening of the mine in 1871 to
the end of 1885 the yield of diamonds amounted to 100,000,000 dollars.
The Kimberley mine produces almost twice as much as the three other
mines combined. The expense and difficulty of reaching the diamond
field in the early days kept away the rowdy element to be found in our
Western mines.
Such diggers as have remained on the field since the "early days" seem
never to be tired of talking of the life they then led as the happiest
they have ever known. Then, each would peg out his claim and go to work
therein with pick and shovel, depending scarcely at all upon the
uncertain help of the lazy Kafir, but with his own strong arm attacked
the hard, pebbly soil in which the diamond was imprisoned, and in a
primitive way "washed" the soil for diamonds. They are not to be picked
up walking through the streets or over the "floors" where the soil lies
becoming pulverised by sun and rain. They hide away and peep out
sometimes after several cartloads have been washed through the machine.
The days have gone forever when a lucky blow of the pick, or a fortunate
turn of the spade, might result in a prize worth a fortune to the
finder. Now there are no poor man's diggings, and one must possess
great wealth before he attempts to seek the diamond in its rocky bed.
The time when a poor man could go to the fields and possibly make a
fortune in the first week of his stay, has passed away.
The mines are now drifting into the hands of a few large companies, and
everybody is looking to the Transvaal, with its budding gold fields, as
the scene of the next South African Eldorado.