Ellsworth American. [volume] (Ellsworth, Me.) 1855-current, 1880-02-12
Notes for PrOspectOrs.
Feb. 9th. 1850.


An easy qualitative test for poor silver
ores, am not acquainted with. The test
involves the use of mercury and mercury
retort or Of cupels, scoritiers and an ASA,
furnace.
The minerals present are the best indica-
ton. and the mineralogy of silver will be
treated Of at length in subsequent articles.
If gold has been found in any mineral. sill
yer is almost certainly present If copper
can be found silver may be present. If cop
per can be found in paying quantity j, is al
ways worth while to ASSAY for silver. for in
working sulphuret ores even one half ounce
Of silver can be protitably extracted, and ex-
perience shows that copper pyrites usually
contain at least that amount. and a trile of
gold.
The next chemical test TO be given is that
for the presence or absence of copper.
The ore should be reduced TO fine pow
der, as described in a previous article. 1t
NAV then be roasted. as described in that ar
ticle, or treated by the following process -
The operations should be done out of doors
or in room with all the windows open. as
the fumes are both unpleasant and unwhole-
some Put half teaspo onful of the ore,
powdered fine and either well roasted or raw,
in a bowl | think a bowl is best, as chem
lists glass ware is fragile. and other glass
ware useless, from its liability to crack on
heating.
If the ore is roasted pour on about two
tcaspoonfulS of strong nitric acid and eau
tiou>lv raise the heat. If not roasted. add
about one teaspoonfnl of chlorate of potash
well powdered. and mix well with the ore ;
then add drop by drop strong nitric acid
Stir well with glass rod or clean stick Of
wood. Add the acid in small portions till
about two teaspoonfuls have been put on.
After it has ceased Tuning warm before.
\ prospector out of doors can warm the
bowl in hot ashes easily. The fumes begin
again but soon stop. Then add very eau
tiously, in small portions, strong ammonia
water-the ammonia fortitor of the apothe
cares-until the whole. when well stirred
smells pungently of ammonia.
Let the mass stand few minutes and then
dilute with a tumblerful of water, stir well
and let it settle. The top liquor, if copper
is present in any desirable quantity, should
be strongly blue or BLUSH green, and can be
easily seen to be so in white bowl. A red
| dish brown mass of hydrate Of iron will
probably be left in the bottom after settling.
1t will usually be advisable, to ensure GER
tainty to results, to pour the top liquor
| which has settled clear into a clear glass
tumbler and examine the color over a white
paper.
This transfer of liquid, called decantation,
can be more readily done by applying a
clean stick to the part Of the bowl from
which you pour, so that the end of the stick
is over the tumbler, and the middle touches
the edge OF the bowl. The liquid will be
found to follow the stick down into the
tumbler and not run down the side of the
| bowl. In this way with little practice,
the clear top liquor can be transferred with
out taking with it the dregs or precipitate,
as chemists call it, at the bottom.
The expense of testing for copper in this
way is only few cents, and the test can
be executed by any careful person. must
again repeat keep out the way of the fumes,
have plenty of air and draft to carry them
of. Keep your nitric acid, strong ammonia
and chlorate Of potash properly labelled and
out of the way Of other people.
CHARLES +. AVERY.