Wisconsin tribune. (Mineral Point, Wis.) 1847-1854, 1853-10-13
A : i YIN G

10 satisfy general curiosity as to the
process OF assaylng we will give in detail
the method as practiced In this country so
tar as 1t relates to coinage. Science has
so far perfected this e.hod as to bring to
comparative uniformity the modes prac-
tlced IN different countries-the main diff
ference being only in the quantity Of metal
used for these trials As the reduced val
ue of bullion is exactly proportionate to
the degree of admixture with her baser
metals, numerous methods had (previous-
ly to the one now III use) been devised for
aScertalnlng such admixture but the un-
certainty, tediousness, and expense attend
lug these have found n happy alternative
succedaneum III the art of asSayiGg as now
practiSed, which unites the indispensable
requisites of precision, dispatch and cheap
ness. In any certain weight of the sub
Ject of trial, the question before the assay
or IS: How much fine gold, or fne silver.
or OF BOTH does 1t contain To ascertain
this fact, ne weighs a small portion with
suitable eXactneSs. submits to the usual
process OF separating the alloy, re-weighs
1T when the operation is completed, aud
makes report accordingly. This opera
| ton is performed in the assay furnace.
which contains kind OF earthern oven or
muffie, within which are placed several
small vessels made of bone ashes, known
by the name ofcopples, or little cups. which.
when sufficiently heated by the charcoal
/ fire, with which the furnace is filed. and
which encloses the muffie on all sides. re-
celve each one assay, wrapped in a prop
er quantity of thin lead These melting
Immediately together, the lead becoming
| gradually and III part converted to glass
/ Serving as menstreum in the vitriiica-
! tlon OF the other base metals. also. these
sink together into the porous substance OF
the coppel, leaving the precious metals on
the surface thoroughly refined which fur
nlshes the process Of silver assay. If
gold is the subject of trial, the ASSAY piece
Is beat thin, made soft In the fire. and.
when rolled lightly together, is put into
a glass vessel containing aquafortis. pre-
vlOusIy heated over a gentle fire, In which
the silver is gradually dissolved, and tue
gold left in state of purity, retaining
the form it possessed, previous 20 the solu-
! ton of silver. To secure the perfection
! OF this process, the proportion of silver u
! gold IN the assay piece should be 2 or 3
/ TO /, which addition, when necessary, is
made before the gold assay is put on the
/ coppel When mixture of gold and sill
yer Is the subject of trial and the latter
exceeds that OF the former, 1T is called sjL
rer putting, and, if contrawise, gold Part
/ ing With the former the assayer pro
ceeds IN all respects as be would with a
s;ver assay, making his report on all the
/ fine metal he finds; but IN gold parting,
he weighs two assay pieces of equal weight
/ one of which he treats exactly as silver
assay, and the other as a gold assay
/ When this is done. by weighing the two
! assay pieces against each other, the excess
j In the former, which still retains the sill
yer, becomes the report of fine silver in
/ the pound. When the subject of trial
contains more than one molety of alloy.
| 1t is denominated metal far gold and slLcer,
and the absolute quantity of each is report
ed The larger the quantity of metal
used In these trials, the less viii any cas-
ual error in the process bear to the whole
mass; otherwise, the quantity is quite in
! different for whatever the assayer takes
/ for his unit or greatest weight, he divides
proportiouably to real Troy weights
Washington Union