66 Alembic for distilling Amalgam of Gold. 
Art. V.—Description of an Alembic for distilling Amalgam of 
Gold, contrived by M. F. Maury, U.S. N. 
Tue common process of treating amalgam, at the gold mines in 
Virginia, consists in getting rid of the excess of quicksilver, either 
by straining, or simply by pouring it off, after it has been allowed to 
stand long enough in a crucible or other vessel, for the gold to settle 
at the bottom. ‘The latter is the method more generally practiced, 
though at the surface or deposit mines, where the gold is found in 
larger particles, the amalgam is freed from the excess of quicksilver, 
by holding it between the palm of the left hand and the thumb of 
the right, and forcing the excess of quicksilver off by pressure. The 
residuum, a friable mass of quicksilver and grains of gold, contains 
from twenty to fifty, or even a larger. per centum (in weight) of the 
latter metal; the per centum being largest when the grains of gold 
are coarse, and least when they are fine. ‘Thus reduced, the amal- 
gam is put into a sheet iron stz/l, holding about a pint, or laid ina 
common shovel, when it is put on the fire, and the quicksilver is 
“blown off.” When the still is used, about twenty five per centum 
of quicksilver, and some of the gold, are lost; but when the shovel 
is used, some of the gold, and all of the quicksilver, is lost. 
The loss of gold is greatest, when it consists of grains or points 
impalpably small; for it appears, that that degree of heat, attain- 
able in the operation of “ blowing off” the quicksilver, is not suffi- 
cient entirely to neutralize the affinity between the two metals. 
When the gold is fine, and the heat quick, much of the former 
passes off with the mercurial vapor: this is proved by condensing 
the vapor, and allowing the quicksilver thus obtained to stand for 
three or four days, when by carefully pouring off the top of it, an 
amalgam, having the consistency of oil in incipient congelation, is 
found at the bottom of the vessel. By subjecting this again to the 
operation of the still, pure gold is obtained. ‘The residuum in this 
case is about ten per centum of the gross weight of the amalgam. 
The metallurgical process of obtaining gold in Virginia is by no 
means perfect; in every stage through which it passes, from the 
stamps to the ‘ blowing off”? of the quicksilver, Wee is a wasteful 
loss of both metals. 
All the gold mines yield more in the small than they do in the 
large way. ‘This difference is the greatest, when the ores are lean ; 
