The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1913-10-09

down of immense bodies of lead, zinc,
and silver bearing rocks must have
freed the sulphides of these metals,
and, in an oxidized condition, they
were necessarily carried into the per-
manent bodies Of water, chiefly the
sea. They may have Travelled in solu-
ton or as exceedingly finely divided
particles of sediment 1t matters not
which view one entertains, there seems
no escape from the conclusion that. If
these metals are and always have
been diffused widely in igneous rocks,
considerable quantities Of them were
gonkian period. The same argument
applies to all subsequent time. If
these salts were carried as sediment
and did not go into solution, they
must have settled with the other sed-
iments and become a portion Of the
stratified rocks. II carried in solution
and never precipitated, they have been
accommodating In the ocean for many
millions of years, Minute quantities
of lead and zinc are known to be pres
ent In sea water, but there is no very
definite evidence as to the amount.
The presence of silver with gold) Is
better known and according to A. I.iv-
ersidge 1t amounts to to grains
per ton. It may be that the quantity
of gold and silver is not such as to ne
cessarily imply precipitation from sea
water since the Archean era. but 1t IL
my impression that In the case of lead
and zinc this could hardly he true. AT
that lead and zinc followed the samt
course as iron. manganese and cop
per
Dec urrsnce Of Occur d'Alcne Deposits,
The ore deposits of the Occur
d'Alene district occur in the Belt SER
les of altered sediments Of pre-Cam-
brian age. The photography Of these
rocks has been thoroughly studied BY
r. c.. Calkins, who has subdivided
them into the Prichard formation,
composed in greater part Of orgillite,
overlain in order by the Burke quartz
ties and slicious shales, the Revet
quartzite, the st. Regis indurated
shales and sandstones, impure lime
stones and argillites, and the Striped
Peak sandstones; the whole having q
presumed thickness of over 1920 feet,
of which over 5000 feet Is accredited
portion of the series which is present
in the vicinity Of Wardner comprises
i thickness of 1890 feet The micro
scopic features of these rocks are
very we'll treated by Mr.. Calkins. He
shows that they consist chiefly of var
liable proportions Of only two min
erals, quartz and serlcite. There are
beds Of practically pure quartzites
over 100 feet thick, but usually the
quartz grains are separated by flakes
of sericite. In the shales and states
there is relatively large amount Of
sericite. and all the grains are very
fine and tend to be developed in al
ternate layers of different fineness. II
is evident that these sediments orig
inally varied from practically pure
quartz sand to fine mud. Whether
they were laid down under marine
lacustrine or continental conditions is
of no Importance in this connection
for in any case they are clearly the
fine debris from great land area OF
Archean rocks and II lead and zinc
are as widely distributed in igneorS
rocks as they appear to be, salts %
these metals must have been presen'
in the water in which the Belt sed'-
ments were deposited, and 1t Is en-
trely reasonable to suppose that to