1sulphur, there is weighed out also a sixth of a líbra and a sicílícus of
copper, if each libra consists either of three-quarters of a líbra of silver and
a quarter of a libra of copper, or of three-quarters of a libra and a
semí-uncia of silver and a sixth of a libra and a semí-uncía of copper. If,
however, the silver contains five-sixths of a libra of silver and a sixth of a
líbra of copper, or five-sixths of a líbra and a semí-uncía of silver and an uncía
and a half of copper, then there are weighed out a quarter of a libra of copper
granules. If a líbra contains eleven-twelfths of a líbra of silver and one uncía
of copper, or eleven-twelfths and a semí-uncía of silver and a semí-uncia of
copper, then are weighed out a quarter of a libra and a semi-uncia and a
sícílicus of copper granules. Lastly, if there is only pure silver, then as much
as a third of a líbra and a semí-uncía of copper granules are added. Half
of these copper granules are added soon afterward to the black-coloured
silver granules. The crucible should be tightly covered and smeared over
with lute, and placed in a furnace, into which the air is drawn through the
draught-holes. As soon as the silver is melted, the crucible is opened, and
there is placed in it a heaped ladleful more of granulated copper, and also
a heaped ladleful of a powder which consists of equal parts of litharge, of
granulated lead, of salt, and of glass-galls; then the crucible is again covered
with the lid. When the copper granules are melted, more are put in, together
with the powder, until all have been put in.
copper, if each libra consists either of three-quarters of a líbra of silver and
a quarter of a libra of copper, or of three-quarters of a libra and a
semí-uncia of silver and a sixth of a libra and a semí-uncía of copper. If,
however, the silver contains five-sixths of a libra of silver and a sixth of a
líbra of copper, or five-sixths of a líbra and a semí-uncía of silver and an uncía
and a half of copper, then there are weighed out a quarter of a libra of copper
granules. If a líbra contains eleven-twelfths of a líbra of silver and one uncía
of copper, or eleven-twelfths and a semí-uncía of silver and a semí-uncia of
copper, then are weighed out a quarter of a libra and a semi-uncia and a
sícílicus of copper granules. Lastly, if there is only pure silver, then as much
as a third of a líbra and a semí-uncía of copper granules are added. Half
of these copper granules are added soon afterward to the black-coloured
silver granules. The crucible should be tightly covered and smeared over
with lute, and placed in a furnace, into which the air is drawn through the
draught-holes. As soon as the silver is melted, the crucible is opened, and
there is placed in it a heaped ladleful more of granulated copper, and also
a heaped ladleful of a powder which consists of equal parts of litharge, of
granulated lead, of salt, and of glass-galls; then the crucible is again covered
with the lid. When the copper granules are melted, more are put in, together
with the powder, until all have been put in.
A little of the regulus is taken from the crucible, but not from the gold
lump which has settled at the bottom, and a drachma of it is put into each of
the cupels, which contain an uncia of molten lead; there should be many
of these cupels. In this way half a drachma of silver is made. As soon as
the lead and copper have been separated from the silver, a third of it is
thrown into a glass ampulla, and aqua valens is poured over it. By this
method is shown whether the sulphur has parted all the gold from the silver,
or not. If one wishes to know the size of the gold lump which has settled
at the bottom of the crucible, an iron rod moistened with water is covered
with chalk, and when the rod is dry it is pushed down straight into the
crucible, and the rod remains bright to the height of the gold lump; the
remaining part of the rod is coloured black by the regulus, which adheres to
the rod if it is not quickly removed.
lump which has settled at the bottom, and a drachma of it is put into each of
the cupels, which contain an uncia of molten lead; there should be many
of these cupels. In this way half a drachma of silver is made. As soon as
the lead and copper have been separated from the silver, a third of it is
thrown into a glass ampulla, and aqua valens is poured over it. By this
method is shown whether the sulphur has parted all the gold from the silver,
or not. If one wishes to know the size of the gold lump which has settled
at the bottom of the crucible, an iron rod moistened with water is covered
with chalk, and when the rod is dry it is pushed down straight into the
crucible, and the rod remains bright to the height of the gold lump; the
remaining part of the rod is coloured black by the regulus, which adheres to
the rod if it is not quickly removed.
If when the rod has been extracted the gold is observed to be
satisfactorily parted from the silver, the regulus is poured out, the gold
button is taken out of the crucible, and in some clean place the regulus is
chipped off from it, although it usually flies apart. The lump itself is reduced
to granules, and for every libra of this gold they weigh out a quarter of a libra
each of crushed sulphur and of granular copper, and all are placed together
in an earthen crucible, not into a pot. When they are melted, in order that
the gold may more quickly settle at the bottom, the powder which I have
mentioned is added.
satisfactorily parted from the silver, the regulus is poured out, the gold
button is taken out of the crucible, and in some clean place the regulus is
chipped off from it, although it usually flies apart. The lump itself is reduced
to granules, and for every libra of this gold they weigh out a quarter of a libra
each of crushed sulphur and of granular copper, and all are placed together
in an earthen crucible, not into a pot. When they are melted, in order that
the gold may more quickly settle at the bottom, the powder which I have
mentioned is added.