Arsenic imparts to copper a very fine white
color, and makes it very hard and brittle. Before German silver was known,
these alloys were sometimes used for the manufacture of such cast articles as
were not to come in contact with iron. When exposed to the air, they soon lose
their whiteness and take on a brownish shade. On account of this, as well as
the poisonous character of the arsenic, they are very little used at the
present time. Alloys of copper and arsenic are best prepared by pressing firmly
into a crucible a mixture of 70 parts of copper and 30 of arsenic (the copper
to be used in the form of fine shavings) and fusing this mixture in a furnace
with a good draught, under a cover of glass.
more about:Arsenic-copper alloy
from:Rare Metals
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