Mohave County miner., 1900-05-12
As to Ore Testing.

,TiT
| al pv the metals in the ores, says
There are assayers who believes the
pro .pector should be encouraged" by
oyerstating the value Of his ore and
who habitually give small returns, from
trace to few dollars ton, upon ore
whca they know to be barren, think
ing 10 keep him at work upon pros
pect which will yield nothing, spend
ing valuable time and money to no
purpose, save that of giving few dol.
lars worth of work to the assayer.
Perhaps the prospector sends samples
TO two different assayers, and one ie-
turns him mo trace" the other gives
value of a few dollars per ton. The
biggest return il usually accepted as
correct. and the mo trace" man is
charged with a failure. Some assayers
say it makes no difference whether
they return mo trace or dollar or
the ore of any value, but the accuracy
of an assay of ore of very low grade Is
more important than that of an ore
carrying hundred dollars per ton;
in the first case a difference between
no trace" aud dollar or two may de-
eide the expenditure of hundreds or
perhaps thousands of dollars in devel-
opment, while in the latter, the ore will
be shipped anyway; and all know that
the Stnelters will pay for nothing but
the actual contents of the ore. These
retur1s of value from valueless ore are
often the result of accident or care
lessness in the hands of an assayer
who has every intention of being hon
est A particle of rich ore left in the
grinder from the last sample, salted
crucible, a loaded cleaning brush, q
dirty mixing cloth, fluxes containing q
little of ths precious metals, these and
other matters of carelessness, unclean
illness or disorder about the laboratory
make the difference between reliability
aud worthlessness in the result of As
saying. The general public is not com
petent to Judge of the qualifications o
an as.ayer any more than those of q
physician. Any man can buy an outfit
for 1908 and stick out his shinglt
Chemist and Assayer," when in real
ity he knows nothing about the cor
rect application of the principles un
derlying the trade be processes. Such
instances are more common thar
many would believe, and sometimes
people of intelligence who would a
once realize the foolishness of hunting
out the cheapest lawyer or doctor viii
give their patronage to such an assaye
just because they can get his service
little cheaper than those of maj
who il competent in his profession ant
who realizes the Importance of takin,
pains.
A good assayer is often charged will
failure because his customer Is ignor
ant of the first principles OF samplinl
ore. Sometimes piece of rock i
broken in two, the halves sent to differ
ent assayers, widely varying results ar
obtained, and one of the operators /
charged with an error. when in fac
both are correct, and the results ar
chargeable to the fact that the meta
was unevenly disseminated through
the sample. 1t is well to remembe
that like results can only be reason
ably expected when the sample is finel
crushed, thoroughly mixed and care
fully divided Tho careful miner vii
treat hi, sample in this way: grindin
as fine as his circumstances will pei
nit, mixing and dividing carefully
aud in every case reserving portion
of the sample so that check assa
can be made II desired As the best o
men are liable to an occasional nis
take, no conservative miner will expen'
any large amount Of labor or none
upon the result Of single assay, bu
will base his future work upon the ecor
curing results of two or more reliabl
assayers.
The best practical test of the quail
fications Of an assayer is his ability I
check with the smelters on their ship
ment pulps, and II You are in doub
with whom, to trust your work go Z
your friends who are ore shippers AM
get them to tell you who they patror
ize, No man can be honest In this bus