The Richmond palladium., 1867-08-22

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% occupy the va.ys and foothills and are covered
with drft-cay. So CT as observed, they the pc
enar rspositori Of the stone. So thorough has
been tho dscompositon that, while il retains its cohe
renee, it ny be shoveled like sand crushed under
the hammer into grans and when It is pulver-
'sed and washed the residum gives traces of TN.
SYSTEMS OF VEINS. -,
Its impossible in the present state of the exporA-
tons to determne the different systems Of vens their
relative sven with precision their direction
much less the effects Of the passage Of the elvans
Porphyritic dykes through the GRANTEES. Even in
Cornwall where the tin mines have been worked from
the earliest historical PERIOD and where the surface
has been penetrated to the depth of two thousand
feet and with all the accumulated experience OF thou
sands Of miners the intrcaces Of that region yet
unrAvaled What Offer then, ~ to the mstaliiferous
lodes Of this region submit with extreme distrust,
confident that my views must be greatly modified by
subsequent explorations. 4+E4 siaa st
There this notable fact which at once strikes the
observer, that there has been displacement of the
veins in longitudinal direction, cutting off their
tinuity-to be resumed, however, when the amount
of that displacemsnt has been determined. That
there will be found all of the phenomena of fractures
dxplacements, cross-courses, eyan-courses, cross
Aucans, and slides, doubt not but the facts thus
far developed will allow OF their ineligible dis
cussion. af5 - 9u- R#T
Thus far, the of tin have been found in twelve
distinct veins Observations to their direction,
where they uncovered only for few lneal feet,
a Of course unreliable and such observations when
plated exhibit no marked parallelism. There ap-
pears, however, to be at least two systems bear
ing northwest and southeast, and another bearing
northeast and southwest. There are indicotions of
e
NORTH ntersected by another system at nearly right
angles. - ,g ala Sc. z-s,es4s,gr zs+ sl-, 4
These odes are true veins, being vertical assures
of indefinite length and depth, and filled with gan
que differing from the wallrock. za5Ef laeol
This wallrock, wherever observed, consists of the
decomposed granite heretofore described, and the
being Of less perishabe mater ia stand
! out in what Cornishmen call "combs."' ~
The veinstones may be classified under two heads:
/. Feldspar, often decomposed into kaolin and
times feldspar and quartz. Q. Sepentine, sometimes
with long 6laments of asbestus. The veins vary in
width from six inches to four feet.
The stone il not aggrega ted in crystals but like
that of Cornwall is mnutey dispersed through the
gangue, and under strong magnifer appears
brownish red delneaton the white ground of the
feldspar and hence is required that the gangue be
reduced to mpapabe powder, thatthe metallic par
tcles may all be liberated from the stony The
density of tinstone G.s) is such that the waste in
washing is much less than that of ordinary metals.
Besides unlike gold or native copper, which comes
out in scales and floats upon the water, tin-stone
maintains its granular form, that its richness may
be brought, by washing and dressing, up TO sxysix
and seventy per cent. and this manipulation is
accomplished in Cornwall which yield but two
and three per cent.
BLACK SAND.
Over the whole of this tract wherever the vegeta-
ton is removed in every road in every yard tramped
by CATTLE in every rl descending from the hillside, is
be black giistening sand, abundant that it
may be scraped up from the surface. From twenty
five to twenty per cent. of this sand is magnetic oxide
of iron, which may be removed by the magnet but
the residue consists of peroxide of ron oxides of tin
and silver in q form which has not been determined.
This sand is the debris of the subacent rocks which
nature has pulverized and washed and it is not i'm
probable that, when tested larger scale, those
rarer metals-platinum, iridium and osmiun will be
found. Some of the reactions indicate the presence
Of gold, metal which is known to exist in this vi
cnity.
ECONOMICAL RESULTS.
The black sand can be be collected in large quant-
ties and proftably reduced but yet quantative
analysis of any Of the vein stones has been made,
and therefore, withhold expression of opinion
to their richness. The specific gravity of tin is so
great that lean can be proftably washed up to
q nearly pure per centage. system Of well defined
veins such here exist, will justify the investment
of atital in their thorough exploration. So far
exposed the vein-stones, well as the enclosing
walls, are in state of decomposition, which, when
sunk upon to the depth OF two three hundred feet
NAV be found to be enriched. s#if ~