DOI Page / Citation link:
https://doi.org/10.11588/diglit.19575#0246
REF 225
bottom, with the faeces of the antimony, the filver and copper
alloy, and fometimes little particles of gold itfelfover it.
But, notwithftanding the gold thus prepared is very pure, yet
the antimony gives it fuch a harfh brittle quality, that it ceaies
to be ductile, and muff, be foftened by the fire with faltpetre and
borax, to bring it to itfelf.
In order to this operation, they prepare what is called a dry
coppel, which is 2 coppel made of crucible earth, which dees not
imbibe like the coppels made of afhes.
When the coppel has been fufficiently heated in the Refining
furnace, they put the gold into it, and cover it up with charcoal.
As foon as the gold is diflolved, which is very foon, by reafon
of the remains of the antimony, they blow it with the bellows to
drive the mineral intirely away, which now goes off in fmoke ;
and add to it, as foon as the fumes ceafe, a little of faltpetre and
borax in powder, which collect the 'impurities, that remained
upon the diffolution, and fix the gold in the coppel in form of a
plate.
Then the gold is taken out of the coppel, and melted again in
a crucible, with an addition of two ounces of faltpetre and bo-
rax in powder to each eight ounces of gold, as foon as it has
ceaied to fume ; and then it is caft into an ingot, which upon
trial is found to be twenty-three carats twenty-fix or thirty feconds
finer.
As to the particles of gold, which may have been left behind
with the alloy, in the faeces of the antimony ; they get them out
by a dry coppel, with the fame meltings and ingredients, as were
ufed in foftening the former.
And when they are certain by the efTay of the fhare of gold,
which that matter contains; they Refine it to feparate the cop-
per, and afterwards make the depart.
As for the gold which may be left flicking to the dry coppels;
they get that out by breaking and pulverifing the crucibles, and
by repeated warnings of the powder of them in feveral waters.
Toe method o/K E Fl Ni N G gold by means of juhlimate. They be -
gin the procefs like that with antimony, i. e. in the fame furnace,
with the fame coal, the fame fire, and the fame crucibles.
When the gold is melted in the crucible, they caff in the fub*
jimate ; not in powder, but only broke in pieces.
The proportion is, if the gold be of twenty-two carats, an
ounce or ounce and an half, or even two ounces to eight ounces
of gold to be refined ; if of twenty carats, three ounces ; and, if
it be only from eighteen to twelve carats, five or fix ounces ; in
which 1 aft cafe, they part the fublimateinto two, and put in one
half at a time, with the gold in a new crucible j which, when
Vol II, Q ' the
bottom, with the faeces of the antimony, the filver and copper
alloy, and fometimes little particles of gold itfelfover it.
But, notwithftanding the gold thus prepared is very pure, yet
the antimony gives it fuch a harfh brittle quality, that it ceaies
to be ductile, and muff, be foftened by the fire with faltpetre and
borax, to bring it to itfelf.
In order to this operation, they prepare what is called a dry
coppel, which is 2 coppel made of crucible earth, which dees not
imbibe like the coppels made of afhes.
When the coppel has been fufficiently heated in the Refining
furnace, they put the gold into it, and cover it up with charcoal.
As foon as the gold is diflolved, which is very foon, by reafon
of the remains of the antimony, they blow it with the bellows to
drive the mineral intirely away, which now goes off in fmoke ;
and add to it, as foon as the fumes ceafe, a little of faltpetre and
borax in powder, which collect the 'impurities, that remained
upon the diffolution, and fix the gold in the coppel in form of a
plate.
Then the gold is taken out of the coppel, and melted again in
a crucible, with an addition of two ounces of faltpetre and bo-
rax in powder to each eight ounces of gold, as foon as it has
ceaied to fume ; and then it is caft into an ingot, which upon
trial is found to be twenty-three carats twenty-fix or thirty feconds
finer.
As to the particles of gold, which may have been left behind
with the alloy, in the faeces of the antimony ; they get them out
by a dry coppel, with the fame meltings and ingredients, as were
ufed in foftening the former.
And when they are certain by the efTay of the fhare of gold,
which that matter contains; they Refine it to feparate the cop-
per, and afterwards make the depart.
As for the gold which may be left flicking to the dry coppels;
they get that out by breaking and pulverifing the crucibles, and
by repeated warnings of the powder of them in feveral waters.
Toe method o/K E Fl Ni N G gold by means of juhlimate. They be -
gin the procefs like that with antimony, i. e. in the fame furnace,
with the fame coal, the fame fire, and the fame crucibles.
When the gold is melted in the crucible, they caff in the fub*
jimate ; not in powder, but only broke in pieces.
The proportion is, if the gold be of twenty-two carats, an
ounce or ounce and an half, or even two ounces to eight ounces
of gold to be refined ; if of twenty carats, three ounces ; and, if
it be only from eighteen to twelve carats, five or fix ounces ; in
which 1 aft cafe, they part the fublimateinto two, and put in one
half at a time, with the gold in a new crucible j which, when
Vol II, Q ' the