ON THE CHLORIDE OF GOLD. 
173 
ART. XLI.— ON THE CHLORIDE OF GOLD. By M. Leval. 
Much difficulty has hitherto been experienced in obtain- 
ing the red and yellow salts of gold, so as to be perfectly 
soluble in water, and without reduction. After numerous 
experiments, I have succeeded in preparing these salts in a 
manner which appears to me to be unexceptionable. 
M. Levol has published in the Journal de Pharmacie a 
good process for obtaining pure gold by means of proto- 
chloride of antimony ; that which I have used in my ex- 
periments has been obtained by this method: — 
First, To prepare the yellow salt of gold, aqua regia, 
formed of three parts of hydrochloric acid, one part of nitric 
acid, and one part of distilled water, should be used. Put 
one part of pure gold into a porcelain capsule, and pour 
over it aqua regia, prepared as above; the quantity of acid 
being double that of the gold employed. Cover the cap- 
sule with a plate of glass, and place it on a water-bath, 
made with a saturated solution of salt ; continue the appli- 
cation of heat, taking care to keep the capsule always co- 
vered, until the evolution of nitrous vapors has ceased. If 
the whole of the gold is not dissolved, add a little more 
aqua regia, cover the capsule again as before, and con- 
tinue the application of heat until the vapors no longer ap- 
pear. The plate of glass should now be raised and kept 
up by a piece of folded blotting-paper, and evaporation 
continued over the water bath, until, on introducing a glass 
rod into the capsule, and withdrawing it, the chloride of 
gold, which adheres, on cooling becomes solid. Remove 
now the capsule from the water-bath, and the chloride will 
soon crystallize in small prismatic needles, of a fine yellow 
color, approaching to orange. 
The chloride obtained in this manner is entirely soluble 
in water, and without reduction. It is employed with much 
vol. x. — NO. III. 16 
