instance,
silver is usually paid for on the basis of 95 per cent of the current
New York price and gold at from $19 to $20 per fine ounce. From this it
is seen that producers reporting in terms of dollars only will
frequently be giving figures corresponding to production below actual
final output of metal, and if they erroneously report net proceeds, as
they sometimes do, their figures are still further below. Other gains
offsetting refining and smelting losses are the relatively small
quantities of precious metals, principally gold, not regularly reported
from the mines, but coming from transitory placer miners whose
production escapes estimate, from stolen ore treated in improvised
"assay offices," and from smelter and refinery cleanings and similar
material. Although mine reports in the aggregate may appear,
therefore, to give figures of gold and silver that are too high, it is
known from actual practice and comparison, later discussed, that final
recoveries, especially for gold, are somewhat in excess of those
reported from the mines.
COMPARISON OF MINT REPORT AND MINES REPORT.
Of
the two plans outlined for ascertaining the gold and silver production
of the United States it may be said that the one is a measure of the
mining industry and the other a measure of the metallurgical industry;
the one reports the production and recoverable content of mine output
and the other the metal actually recovered in marketable form. The two
methods will not produce exactly corresponding results nor should they
be expected to do so. In addition to factors already noted as causing
differences between the two sets of figures, it must be remembered that
it is not always a simple matter for smelters to distribute their
output according to the exact origin of the ore, and it is still more
difficult for refiners to do so. It is therefore always possible that
some ore of Canadian or Mexican origin is contributing to the output of
metal thought by smelters to be of domestic origin.
The
calendar year covered by both investigations is the same but the period
of mine production naturally corresponds to a period earlier than the
period of actual production of marketable metal by the interval of time
necessary for transporting, sampling, and treating the ore and for
refining the products. This interval is
K
practically
negligible in the case of placer and mill bullion, but may be several
months in the case of crude smelting ores and especially of ores
concentrated before smelting.
The
figures for the mint report and the mines report for a period of years
sufficiently long to compensate for overlap or lag should agree within
allowable limits of error due to the complex nature of the ores and of
the methods of treatment. The figures of the mines report may be
expected, on the whole, to fall normally below those of the mint report
for the reasons outlined.
