The weekly miner. [volume] (Butte, Mont.) 1878-1881, 1880-04-06

the origin of mineral veins, ores, ETC., says
In one sense all ores are native. in another
sense they are not. Thus, the ore of any
metal may be called native, because it is a
natural product, so found, but in another
sense the metal is native only when found
pure and unalloyed, or uncombined mcchan-@
ically or chemically with other substances.
Some ores bear no resemblance to the metal
which is their basis, as, for example, oxide OF
zinc; here the color, streak, malleability and
weight, all vary from that of zinc, SO that il
bears no resemblance to zinc, either in appear
ance or physical qualities. The same is true
of malachite, carbonate of "copper", which
bears no resemblance to the metal. This
divergence from the metallic base has great
similarity to the same thing in pure chemical
combinations seen in labratory work; yet
while it is usual, it is by no means universal.
Thus, lead ores usually resemble lead, as
galena is often taken for lead, n many per-
sons, on melting a piece of rock containing
galena, and seeing the lead run out, would
imagine that they were merely melting out
the lead but in reality native lead is not
known. 81.
OF the various metals whose ores are found,
it is a significant fact that som are practically
always found native, and others never so
found. Thus, gold is ar example of the first
class and iron Of the second, the only native
iron being found in rocks Of meteoric origin.
Again, some metals have a great affinity for
sulphur and oxygen, and it is this class of
metals that are never found native. Thus,
iron has this affinity, particularly for oxygen,
especially in the presence of moisture, so tha,
if all the iron in the globe had originally been
native, it would not ever have been found so
now, as in consequence of the action of the
air and moisture it would all be rusted.
Gold and platinum, as they have no such
afinities, belong to the first class; but, besides
that, there is still another class of metals
which occur native, such as silver, copper, etc.
This arises from the fact that the combine
tons which they first formed were readily de-
composed and the metals set free.
The question arises, Whence came all
these ores? As it is we'll known, they are
generally found in veins, or rather there are
what were apparently assures in the earth,
which are now filled with these ores. The
old notion was that the interior of the earth
was a vast reservoir of precious metals, and
that, in the process of cooling, cracks or fs-
sures were formed in the earth's crust, and
the metallic compounds forced up from the
centre in a liquid state, and gradually cooled
and crystallized. In other words, they were
supposed to be of the same origin as the nu-
merors trap dykes that we find everywhere.
But these dykes which were formed in this
way never contain any trace of metallic ele-
ments,
What, then, was the source of all our me-
tallic ores? In a word, it was the primeval
ocean; this was their grand source. This is
no theory, merely, but is capable of demon
%stration. The waters of the ocean, even to
the present day, contain traces of the precious
metals silver in exceeding small quantities,
bnt gold is present in very appreciable guam
titles. A French chemist, after many analy-
ses, found that sea water contained on an
average about one grain of gold to the ton,
and from the amount of sea water, it is esti-
mated that there is to-day present in it more
than 10000, 600. 1000 times the amount that has
ever been mined. How can this enormous
wealth be obtained and utilized? THIS is tile
problem for some modern chemist to solve
to obtain some substance which will precipi-
tate the gold, the same as a plate OF iron will
precipitate the copper from a solution of copper
sulphate. To explain how thisa ancient ocean
contained all these metals in a state of solu-
ton, we must go back to the condion OF
things at this time. Before there vas an
ocean, the water was all in our atmosphere,
and even when it began to be precipitated it
was in a continual state of perturbation, and
the first water formed must have been under
an immense pressure and have been intensely
hot. Now it is we'll known That water under
these conditions has intense solvent power,
and would dissolve even some of our hardest
rocks. This experiment has been tried, and
water has been enclosed in strong glass tubes
containing different ores and rocks, and then
intensely heated, when it was found to have
dissolved part of the glass and attacked the
most obdurate ores and metals. Quartz es-
pecially was particularly affected. In our
National Park, the solvent power of hot water
is seen where the geysers are surrounded by
stalactities of quartz, which have been formed
from the water flowing from them. This
extends also to ores of metals. Now nearly
nine-tenths of all such ores are combinations
of the metals with sulphur and oxygen.
Now the %sulphates Of all these metals are
soluble, so that being dissolved by this ocean
they remained in a state of solution. This
then was the condition of the ocean just be-
fore it began to bear life.
A chemist once had a solution of sulphate
Of hon in jar, which upon examination one
day, after having been long forgotten, was
found to have partially crystallized. On
breaking open the mass of crystals, he came
to a quantity of iron sulphide, in the centre
of which he found the bones of a mouse.
The mouse had fallen into the jar, and sui
plate OF iron crystals had been deposited
about its body. The flesh began to decay,
getting the necessary oxygen from the sui
plate of iron, which was thereby reduced to
sulphide. This little accident completely
illustrates what went on IN that old ocean,
whereby it deposited its treasures of metals.
Ille appeafeu, anu ueatn anu uecay chSueu.
The decay of all this animal and vegetable
matter reduced the sulphates to insolubie
sulphides, which were deposited. In this
way do we account for the diffusion of the
various %sulphides throughout the great masses
of stratitied rock. Thus, pyrites are found
everywhere, and the most fossiliterous strata
contain the greatest deposits Of sulphides.
This does not, however, as yet, account for
the veins. They were evidently formed by
l. .titration, in some cases; that is, being under
water the metallic substances were filtered
into them; but with the exception of a few
veins of chloride Of silver, this does not ac-
count for their formation. Mineral veins
generally are veins that traverse various
s.,ata e Lalasi.ai .ai. s.i .>... f.; a..