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THE NATIVE PROCESS OF WASHING. 73
water,
and the process is repeated; and so on until but a little blackish sand
is left behind. Then more crushed quartz is put in, and the operation
begins as before. This process is repeated again and again. Each time
the sediment becomes richer and richer, until it is determined to
finish the operation, and get rid of as much of the sand as possible.
The
tray now requires more delicate handling. Less water is used; and that
is poured in gently upon a slope. The lighter particles are thus
carefully washed to the edge, and brushed out with the hand, every
grain being visible. After this washing has been continued for some
time there remains but a very little sediment, and this contains the
gold. The fact is at once rendered apparent, by tilting the tray and
permitting a little water to trickle slowly over the contents. The
particles will move gently towards the edge, and the gold, being the
heaviest, will be the last to move, and will soon appear as a yellow
rim at the top border of the sediment. The Korum-bers work very
roughly; and I am satisfied that they lose a great deal of the precious
metal that would be taken up by the quicksilver in our modern and more
delicate process. Besides which, the gold sometimes exists in the form
of film, as fine as gold-leaf, and this will float on the surface of
the water, and is, therefore, liable to be washed away.
It is necessary to understand this operation of washing, because wrong conclusions may very easily
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