The Abbeville press and banner. [volume] (Abbeville, S.C.) 1869-1924, 1897-04-28
AA a vein OF igneous fusion.
BIB a vein Of segregation.

Veins are rock matter filling the cracks o.
fissures OF other rocks. They vary greatly II
size and extent. They may be regular or ir
regular in form, isolated or united in a com
pleX network. The phenomena OF veins are
such they cannot all be referred to the same
cause. In some The vein stuff has been pro
truded as oike, differing from ordinary
dikes-only the accidental circumstance tina
it contains metal.
Mineral veins are not, however, generally
filled by injections from below, or rather they
are not generally found At the surface.
Should mountain or hill tops be worn TO
level, as Is found in Arizona, views o fIgneou
origin would be found vertical. In this coun
try such veins are below the base of the hills
and guided by out-crupS they can be pene
trated.
The ore In veins often varies in richness a
different depths o: passes into ore of some
other metal. The ore also varies in kind anC
quality according TO the character OF the roci
through which the vein passes.
These phenomena are best explained BY
supposing that the sediment, of which tn.
strata were formed, contained the minera
substances OF these in small proportions. Al
ter they became solid and hssures had beeI
formed the mineral substHn was transferred
by SLOW segregation OF matter from adja
cent rock 10 the issures and deposited.
The fissure veins In the section of the Lit
tie Mountain are generally difficult TO diStin
guiSh rs such in the sla'es above the water
Aloug the planes of stratiticat!on, and L
some extent along the clearage planes, quart;
ciated with Irregular quartz insertions in the
Slate are all 10 show their presence. Thei
submerged structure is much more eviden
in either q slate or granite tissure.
Another reliable feature in favor of the golC
veins in the mountain section is, that tn,
walls In which the veins are encased, are 0
the same geological formation with few ex
ceptions. When volcanic rocks appear ir
large quantities, contact veins may be ex
pected. They are encased in two distinc
porphyry and slate. Snch veins are inter
spersed with barren places. The genera
strike OF veins here Is northeast and sout h
vest, and the dip or angle which the ont
crops make the plane OF the horizon is north
and under water where the veins take thei
regular form, the formation becomes vertical
1t Is found that those veins only are produc
tive that have this direction. bikes appea
IN every direction.
The age OF the ore deposits here is late
than that of the force which produced th,
stratihed rock from the fact that fragments O
sheared country-rock are not rare in thu
qualtZ.
The assuring force was. therefore, after tn.
Shearing force.
The fissures through which the veins as
cends in the Little Noun tain section acts a,
wonderful reservoirs for water which is ar
evidence Of their continuance downwards il
compactness of the formation below vale,
level is evident that when the precious NJ etal!
were arrested the letters were permanent.
LII the strata were as permeable from wate
downwards as II is from the surface to water
the water which falls upon the surface woult
gradually SETTLE through them TO the level 0
the sea, or If the strata were impermea bl,
above water as that below, the water from TIT
fissure would rise and pass over the surface
and be collected In the creeks below.
The strata above water is nearly as porous
as sandstone, with quartz tissure out.crops
Such formation holds very little gold, AM
nothing short OF underwater mining In hi
section will return the outlay of miuin
venture. /. w. Hutchison.