Tonopah bonanza. [volume] (Butler City [i.e. Butler], Nev.) 1901-1909, 1904-06-04
TONOPAH BONANZA
LEAD ORES.
Some Notes on Their Varieties
and Occurrence

VI 20 VI EAAl1s AAAa III .
Quartz, barite and calcite is most
usually the gangue of lead ores and
in certain districts the mineral huor-
spar is frequently the gangue rock.
There are known ninety-two metals
in which lead is contained as a chem
zeal compound and it surpasses all
other metals in number of species.
1t occurs in almost every known color
and the different forms of this mineral
are regarded as being the most beau
tiful and interesting specimens in the
mineral cabinet. A few OF the best
known varieties Of color are galena
which is lead gray; cerussite, white;
~crocoite, bright red; pyromorphite,
green, yellow and brown; w%ulfenite,
yellow and red; l~inarite, azure blue;
and minimum, bright red mixed with
yellow; in its native state it is ex-
ceedingly rare but The lead mines of
Sweden have produced some beauti-
full specimens. Lead is the heaviest
of all the base metals and there are
but three metals of commerce that
have a specific gravity exceeding it,
viz: gold, mercury and platinum; it
is also one of the oldest known metals
having been used by Egyptians and
mined bv the Greeks and Romans in
Spain, Greece and England. The
lead carbonate ores, anglesite, lead
sulphate, and cerussite, it is said were
not originally deposited as sulphates
and carbonates. but are mainly the
result OF oxidation from the sulphide
of lead, galena. These forms of lead
are seldom, il ever, found as originally
deposited, they having through chem
ical changes gradually altered their
composition, and this is the history
Of many of the mineral species. The
sulphate of lead anglesite, formed
usually by the oxidation of the sulph-
ide, galena, is in most cases the com
pound from which the carbonate,
cerussite, has resulted through ac-
tion of circulating waters holding in
solution alkaline or earthly carbon
ates. Anglesite frequently occurs
with cerussite, and thus is shown the
transition between the sulphide and
the carbonate. Anglesite and GER
ussite ores will as a rule always be
found near the outcrop of galena de-
posits. In carbonate Of lead ore,
cerussite, the richness varies consid-
erably according to locality. If ga
lena only has been oxidized then the
resulting carbonate is likely to be
rich, as, for instance, cerussite ores
of Missouri have been known to carry
" per cent lead and the same car.
Donates at Lone Mountain, New, in
the Alpine and Tonopah.
Belcher mines and others often carry
over 20 per cent lead with high values
in silver, a very high average.
In Colorado cerussite ores have
been known to produce but a small
percentage of lead and for the reason
that the oxidation or decomposition
action attacked also the country
rock, communicating the ore so as tC
diminish the percentage of lead below
"a profitable basis. One of the most
abundant of lead ores is lead glance
or sulphuret Of lead more commonly
known as galena; when the contents
of this ore reaches several ounces o.
silver it is known as argentiferou:
galena, and when carrying appec
ciable values in gold it is called auri
ferrous galena. Galena pres almost
invariable carry silver values, a no
table exception being the great zinc
and lead district of Joplin, Mo, where
these ores are wholly devoid of silver.
Opinion varies as to the richness o.
coarse grained or fine grained galens
ores, some authorities asserting tina
the coarse grained variety is always
poor in silver and that only in the
line granular variety will any great
amount Of silver be found, exceptions
to this are some coarse grained
galena ores from Idaho which have
been known to carry 1900 OF. of sill.
yer to the ton. In sand carbonates
the lead is in the form OF feather-lik
CRYSTALS formed durinp the pyanor.