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To Fuse Gold Dust
Uses such a crucible
as is generally used for melting brass; heat very hot; then add the gold
dust mixed with
powdered borax; after some time a scum or slag will be on
top, which may be thickened by the addition of a little
lime or bone ash. If
the dust codtains any of the more oxidizable metals, add a little niter, and
skim off the slag
or scum very carefully; when melted, grasp the crucible
with strong iron tongs, and pour off immediately into
molds, slightly
greased. The slag and crucibles may be afterwards pulverized, and the
auriferous matter recovered
from the mass through cupellation by means of
lead.
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