The Placer herald., 1866-04-21
SULPHURETS.

IL may De useful 10 miners and prospect
ors to know that the sutphurets of silver,
lead, copper, and iron assume an almost in.
definite variety Of forms, and present great
diversity of appearance.
The sul pburets of silver for instance, are
black, and crumbly, at Others,
grey or red, very hard and stoney; and be.
ing generally combined with the sulphurets
of copper, antimony, iron, arsenic, and other
metals, they vary in color according to the
extent of such combination. For these
causes it is utterly impossible, by description
alone, to convey any correct idea of the ap,
pearance of the sulphurets of silver. Miners
would do we'll TO examine we'll arranged
of specimens of these sui phurets,
to judge OF their appearances.
There is one sui phuret of copper. which
owing to the enormous production Of it
from the mine at CopperopoIis, has become
familiar to almost every man, woman and
child in the country. This is the yellow
gists, chalcopyrite-c chalco being the Greek
word for brass-which this sulphuret very
much resembles in color. There is another
sulphuret of copper of quite different 1sp,
pearance, which is much more valuableo7Jt
is called the grey sulphuret, or copper gasse;
this is much heavier, and softer than the
other, and looks more like iron-sometimes
like blackead, it contains upwards Of 70 per
cent. of copper, or more than double the
proportion contained in the best yellow sui
phurets, which sometimes do not contain
more than to 10 per cent. though looking
like much better ores; as rule, the paer
the poorer are the yellow sulphurets.
The sulphurets Of lead, or galena, are too
familiar to everybody to require description
here. But it may not be generally known
that this sul lpburet has number of forms
in which it crystaizes. As rule, the vari-
ETY. consisting of the smallest crystals, OF
granular, contains the largest percentage of
silver.
The sui phurets of iron are among the
most wide spread mineral products in ma,
ture. While all the other sulphurets al
the metals are confined to certain classes of
rocks and are limited to certain geological
ally omnipresent; they are in all the geolog
ical formations, from the oldest to the newest,
and are not confined to the mioeral kingdom
but are found in buried trees, bones, and
other animal and vegetable substances.-
While the most familiar form of these sui
purets is the cube, and their color is pale
yellow; they are found in forms that some
times battle the mineralogist to detect them
without testing their compositions; and they
vary in color, from an almost silver white
ness to a black, shining like coal. As a
general thing the amphorous variety, or such
as do not assume any geometrical form,
when Of yelowish color, are the richest
in gold, the cubical the poorest. The gold
in all cases is combined in a metallic state,
as in the the case with silver, chemically
Gold has no affinity whatever for sulphur,
and therefore, never chemically unites with
it; while silver having strong affinity for
sulphur untes with it in innumerable pro-
portions.
Arsenca pyritos, or mispickel, as it is
termed by mnera ogists, presents very much
the same appearance to the inexperienced,
as mnndic, an amphorous variety of sui phur-
OF of iron, usually found in the vicinity of
veins of the sulphuret of copper. But it is
very different in composition, and almost
always contains gold or silver, on this coast.
1t is more the color of new steel, than nun.
die; and the form of crystals, when they OK,
list, is like the figure of the diamond on a
common playing card, never cubical like
those of iron. We should recommend every
miner who may meet with any ledge Of
rock containing any description of sui phur-.
cts in considerable quantity. to send speci.
mems of the same to this office, or to some
respectable assayer, to have them analyzed.
The owners of many of the richest mines
in Grass Valley, obtain nearly all their gold
from the sul lphurets contained in the rock
As general thing, a vein of auriferous
quartz, containing suIphurets, is more likely
to pay permanently, than ledge containing
only free gold. These latter veins occasion.
ally contain immensely rich pockets, but
they rarely.continue to pay for working for
any great length of tines. f. Miner