cOLOURING
GOLD
PIECES
It
is not about to add colors, but to show up the natural coloration,
lost consequently of the
alloy process.
Eliminating
of the superficial part of gold, by
means of corrosive process,
the other elements that
constitute the alloy,
its original pure gold
aspect is restituted to him.
Recipe:
saltpeter
.................... 200
g
sodium
chloride ........ 100 g
water ..........................
30
g
hydrochlorate acid….
90 g
Both
first elements are diluted in tenth of their weight of water, that is to say:
if saltpeter plus
the sodium chloride is 300g,
the amount of water will
have to be 300/10 = 30 g.
and to this
will be
necessary to add next the 90 g. of hydrochlorate acid