_Ore Dressing, etc._--This consists simply in the separation of the ore by
hand at the mines into different qualities, by women and boys with small
hammers, the process being that known as "cobbing" in Cornwall. The object
of this separation is twofold: first to separate the rich parts from the
poor as they come together in the same lump of ore, otherwise rich pieces
might go undetected; and, secondly, to reduce the whole body of ore coming
from the mine to such convenient size as permits of its being fed directly
into the stamps battery. The reason for this separation not being effected
by those mechanical appliances so common in most ore dressing
establishments, such as stone breakers or crushing rolls, is simply
because the ores are so rich in silver, and frequently of such a brittle
nature, that any undue pulverization would certainly result in a great
loss of silver, as a large amount would be carried away in the form of
fine dust. So much attention is indeed required in this department that it
is found requisite to institute strict superintendence in the sorting or
cobbing sheds, in order to prevent as far as practicable any improper
diminution of the ores.
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