St. Landry democrat. (Opelousas, La.) 1878-1894, 1884-05-10
The Origin of Ore.

ture by Prof John A. Church, deilyefed
to the pupils of the public schools ID
Tombstone, Arizona: \,
No one has ever seen ore IN process OF
formation, but something has been
learned of it's formation, and Will try
and tell you how it is deposited IN
Tombstone. In the human frame there
is circulation OF blood passing IfoEh
the heart through the system aud back
to the heart. In plants there is circu-
lation Of the sap; the earth has its cir
!culation-water comes to 1t, passes
through it, and rises again to its surface
n the form of springs. The first thing
to he observed is the rainfall passing
into the rocks. Rain penetrates more
than twenty miles into the crust OF the
earth: it dissolves substances-ore as
we'll as sugar. When we wish to ex
! tract the silver, we add salt and blue
stone every substance can be dIssoly-
ed in the water, even the quartz; lime
stone is readily dissolved. Rain water
in passing through the earth takes up
minerals 80 lime, iron, potash, etc. -
which are deposited III the interior OF
the earth, and then return again ID the
| form of springs. The rainfall IS pure,
but the springs are not pure, Tor they
have taken up these mineral substances
/
mn oxygen and nitrogen. When these
combine with solid rock, the rock is
said to be hydrated. This air is passed
inward through the rocks as the water
passes downward. These form springs.
In addition to water and gas, the earth
has circulation of solids; sea waves
beat oil the rocks and wear them away
where those particles are coarse, we
| have pebbIes !; where smaller, we have
coarse sand smaller yet, mud, portions
| of limestone. Sea beaches are found IN
the mines of Tombstone.
I When these particles are first worn OF
! they are borne away-the finest partl-
cles borne far away, and called shale.
| In the mines of Tombstone are found
| limestone, quartz and shale; which
proves that where we now stand, on the
| hills of Tombstone, it was once deep
4 water.
This history Of rocky sea cliff is the
history of whole world. The world
was originally composed of gas, much
heated and then cooled, like the Volca-
noes of the present day, where the top
goes to the bottom and the bottom
comes to the top. ].
No one has ever seen the original
earth. 1t cooled gradually from a gas
to- solid. In this-way the chemist tries
to obtain pure water: He takes water
as pure as he can find it, heats it, then
coOls the steam aud repeats the process
/ until he gets a pure water. III this way
quicksilver is purified, and camphor
1 cum. SO, a gas will cOndense into a
solid, and a solid may be heated until it
i becomes gas.
| This earth was once gas, heated and
then cooled, until it became solid: 1t
lis by these circulations of water and air
| that the ores are collected together and
found in one place. If we were to see
the original earth, unacted upon by the
4 calculations which have attempted to
4 explain to you, ne should ind the
quantity OF metals i'll rock very, very
small.
1, At Comstock Lode, Nevada, are found
volcanic rocks which contain % per cent
silver, and gold 45 per cent. So in the
eruptiye rocks of Leadville, Colorado
the proportions of gold and silver have
been found to be similar. The geolo.
J, gists have been able to show how many
! tons of rock must have been dissolved
to give this per cent of precious metal
1.-The waters found holes, OF creyices
| where they could deposit the metals
they had taken up, all of which are no.
deposited $500 feet or Que mile below
the surface of the earth, so that minins
: for these metals will not be carried AM
Farther than one mile below the earth
i surface, though the water penetratet
:. 30 miles into the earth; the deeper TIN
= WatersgOes the more the pressure, ant
. when you increase the pressure y0t
q must increase the power OF solution
releasing the pressure also releases tn
metals; the waters passing through tn
a rock are forced now slowly, now NOR
. rapidly, aud when such waters reach tn
! crevices there is much less speed OF tn
waters, and tile metals are depositet
!. there. In regard to the deposition o
1 ores, scientists show us that the rock
have been acted upon again and agall
! by water, and in this way the ore is col
lected. 1t is difficult to distinguish til
!. age of the rocks, but they haye show
where the first concentration OF til
metals i'm the oldest rocks known CAV
= yield Of only one-half cent to the tor
It The part of the circulation which col
al lects metals is called the function Q
! the circulation.
No one knows why the precious met
Z ais are deposited III veins or in beds
but one thing can be silOWn-that wteI
these ores are found there are eruptiv
= rocks. In the western part OF our couu
u try this is especially true.
e Where not only shales but dikes al
i found, where melted rock has bee
: forced to the surface, butsbY the actio
+ of water has been carried beneath I'll
'-.I surface, which show eruptive forces |
l. work, SO it is in the hills Of TombstOr
4 forces as simple as the ordinary fore.
that work iii every hOusekeepeT's kitcI
e en- or chemists laboratory. Republ
te can.
4 Cotton, continues to be the king
u II. +NEs r1x%