Sierra County advocate. [volume] (Kingston, N.M.) 1884-1960, 1894-04-20


casions have we chance to see one
OF these nuggets exposed in place
or Its parent vein
| On the chemical precipitation"
theory side, some claim that salts
of iron dissolve the gold, that veins
bring down grains and nodnles and
masses of pyritss and that the
gold in these masses is reduced by
the persalts of iron and precipita-
ted sometimes through the medi-
um of organic srbstanees) into
masses. the element of the pyrite
such as its sulphur and iron, pass
off, the one into sulphuric acid, the
other into iron oxide, the latter a
frequnut associate of gold nuggets.
The size Of a nugget would thus
he proportioned to the original
size of the nodule or mass of py-
rites, the former especially If the
waters be alkaline In tiaversing
glavels, alkaline waters would be-
come neutral oI acld, and unfavora.
BILE to the precipitation OF silver
with the gold. Hence the purity
of Drift or "placer" gold and its
comparative freadom from an alloy
OF silver, tho silver being lost in
transit. Which would seem much
more reasonable than that silver
could be leuched out of hard gold
nugget IN the placer. BY such
chemical precipitation then, the
pitted appearance OF the nuggets
would bs accounted for, resulting
from unequal strength of gold So
lutlons Certainly the pittsd
mammillary Appearance of a mug
get is very remarkable and more in
accord with some chemical s"lu-
tion theory than that this form
could be produced by mere water
action alone).
Against the chemical precipita-
tion theory Is what may be called
the mechanical one, whose argu-
ments are that
l. Deposits OF placer gold are
found adjacent to aad lying below
districts traverssd by gold veins
2. Areas whsre quartz veins oc-
cur have suffered great erosion and
forces have there been !
very active.
3. The condition in which placer
gold is found, viz, mingled with
rolled fragments of quartz and in
depressions of bed rock
where workings have been on
large scale aud would have left it.
Chemical solutions would not be
thus localized and eircumstanced.
4. Distribution OF gold in placers
demonstrates its mechanical origin.
Nuggets and coarse gold are gener-
ally found nearest the outcrop of
luartz veins that supplied them
whilst PARTICLES, became generally
smaller as they receded from this
source.
5. In some placers fragments Of
,old bearing quartz are found like
most of the neighboring veins and
noet nuggets have more or less
luar,z, like that of veins still ad
lerine to them.
6. The surface of nuggets often
hows evidence of hattering and
wear as by stream action.
7 Ii gold of lplacers were from
we should find much of
crystalIized and forming strings,
nd sheets running through porous
Gold crystals do not occur in
,lacers, all grains sre waterworn
fragments.
As good example OF mechan I
cally formed placer, the late Prof.
?. S Newberry cites one from Os-
cola, Nevada. On the west flank
f Mt. Wheeler are rich placers.
he centrel mass Of this mountain is {
rdnlte, surrounded on the nauks |
" nplurned states. limestone and ,
uartzit 9. All these rocks are
reversed by quartz veins, those in
aartzites and limestones are bar
IN OF gold. The quartz veirs in
late belt are Numerous and rich. l
he slate area is eroded into hol-
Nv smph,theater, drained by sew
raj gnlcbes, oil uniting IN one,
Irough which all the debris OF the
,ounuin has been spread out
yer tks slopes Of the valley below.
his debris is 300 feet thick. II Is
ON posed OF bnulders and pebbles
{ vein quartz and in clay derived /,
-om decomposition Of the slstes
Ii this contains gold. Near the
cad of the guleh il is cosres, aud ]
Glow becomes finer and fner to. q
ards the valley, q
The climate ia now dry, but oc-
asional streams have cut narrsw
hannels through the beds of
rsvel; and boulders in the upper