The Idaho world. [volume] (Idaho City, Idaho Territory) 1864-1918, 1866-09-22
Requisite. Of : Regular Metaliferous Vein
By F. soHrRMER.

BY r. SCHIRkER.
Assayer and Analytical Chemist, and Graduate Of thu
Freiburg, Germany, School of Mines
A vein, or lode, should have two regular
aud we'll defined walls, which are called re-
lspeetively sffootn and changing walls
These walls should be smooth to certain
extent and the foot wall, particularly, should
be firm aud solid. The salvage (auccan Of
the Cornish miner) should fit loosely into the
walls of the country rock.
Below water level the water should flow
freely IN theIode, while the country" neigh
boring rock in which the vein is formed is
comparatively dry. A great affluence of
water is one of, the best indications of the
persistency of a lode in depth as it indicates
a continuous openness of the vein assure.
"A vein of a crystalline nature with great
many druses and vuggs, while the gangue
rock is compact, is of highly promising
character Every collection of ore in the
vein should be massive, and not in scaly or
thin streaks, and coatings on the face of the
openings and joints of the gangue rock. The
distribution of ore among the crystals of
quartz and other gangue rocks is also cousi-
dered a favorable indication by the practical
miner.
"Shiftsd and " slikensides" are interest
ing ard encouraging features of vein,
demonstrating thesenergy and extent of the
rupturing and injecting forces.
ILsis general law of metaliferous veins
that they change their character while pass
ing through different rocks. If they have
been productive in certain species of rock,
they often become less productive, or even
poor, in striking another. The instances are
not rare where they become quite barren for
hundreds of feet; but@should the above
named favorable features exist in a vein,
temporary diminution of the width of lode
or the scarceness of the ore should not dis
courage the adventurer, for as soon as a fla
vorable strata is met they resume their former
prodnctiveness. We have many examples of
deterioration OF veins in depths, but the most
striking instance is the one of the "Samp-
SOM shaft, in silver mine in the Hart noun
tains, several years ago, where the abandon
ment of the mine had already been decided
upon, when suddenly, at depth of $500
feet, such a concentration of ore was struck
as exceeded the former productiveness of the
mine.
Another point, which is also important to
notice in regard to the value of lode, is the
character of the "couutry rock" for although
this rock does not necessarily influence the
character and contents of the lode, still ex-
perience reveals to us the fact that certain
rocks are more favorable for the formation of
metaliferous veins than others.
The gold bearing rocks belong entirely to
the primary crystalline series, and meta
(azoic) rocks, and not to the fossil
liferous or sedimentary. The auriferous de-
posts and placers are produced byth disin-
tegraton of these granite, diyritic rocks.
There are no ores of gold, as is very often
improperly mentioned, as gold is never found
in nature, but frequently alleged
with other metals, such as silver, copper,
palladium and tellurium.
Silver is found principally in the above
named rocks, but also occasionally in the
'Primary fossilliferous and Secondary Sc
RES" Native silver is found in proportion to
its entire production only in uncomfortable
quantities, and then chiefly in shallow depos-
its near the outcroppings of its veins. More
it is produced from the genuine
silver ores, which are combinations of silver
with sulphur, anthony in different proper
tions, silver with sulphur and arsenic, silver
with sulphur, arsenic and copper, silver with
anthony, sulphAr, copper and iron, silver
with sulphur, silver with antimouy, silver
with copper and sulphur, silver with iodines
with bromineand with chlorine, silver with
silver with quicksilver.
large quantity is also combined with
other ores, such as the sulphurets of lead,
copper, iron, anthony, cobalt bismuth, ar
senic, but chiefly lead also with other ores
of copper, which are sometimes SO rich that
they are called sssilver ores" u-.
In regard TO the theory and hypothesis of
the formation of metaliferous veins, which
are plentiful amongst biologists and miners,
will state only the following, which think
throws light upon the subject:
Mr.. Daubiee shows that solution of q
basic alkaline silicate when heated to $50
degrees Fahr., deposits great deal Of its
silica as crystalline quartz. The heated Al
kaline solutions, which are at the same time
the agents of metamorphine, dissolve from
the metallic elements which these
disseminated, aud subsequently de-
posts them with quartz and the different
spars in the assures Of the rock.-[Denver
News. - 46 &h+8
The S. F. Flag feels badly. It's friends are
being kicked out Of Office. The Flag reven-
ges itself with the following sarcasm:
At latest dates the dexterous Andrew was
sitting cross-legged in the National shop,