Weekly national intelligencer. [volume] (Washington [D.C.]) 1841-1869, 1845-06-14
COPPER MINES OF LAKE SUPERIOR.

CorrEh MINES OF LAKE SUPERIOR,
AT a meeting of American Geolooists and Natu-
raliss at New Haven lately, the following commu-
nicaton OF interesting facts relative to the recently
discovered copper mines Of Lake Superior was
made by DR.. G. 7. JACKSON, of Boston:
Professor JACKSON had said in his statement that The islands
between Lake Huron and Sau st. Marie were Of the same
fossiferous character the limestone Of Niagara Al the
Sau TO the red sandstone. Here the I,anIs ar
two three miles wide and nearly mile long do fl Il
about eighteen feet Il would be very easy make canal
round them, the excavation for the whole mile would lie IN
soft gray sandstone, easily blasted, and the sides which
would form good walls Tor the locks On the Hat ground be-
tween the Sau Village and the Lake there large quantity
Of boulders Of many weights of senite pohy, green
stone, trap rock with epdoe and sandstone These have
all been brought hher by drift ice and have abundant
proof Of this all along the shores Of the lake. There
wemaked old shores Of the lake. One is gravely beach,
short distance off, and another is at the base Of the hills
and there is large bog between the two. The soil on the
nus Is good and supports fine BIRCH larch,
and Norway pine True, there is limestone the bor
des OF the lake. but there veins Of cicareous
SPAR enough for all the purposes Of fuxng the copper
and The Old red sandstone which is found up the lake will just
do to build the smelling furnaces with The rocks dip all
round the lake towards the angle about eighteen
degrees, and run northeast and southwest The prevail
ing rock in the neghborhood of the copper il coarse con-
glomerac, with trapdykes ntersecting the hydro
scae OF "copper" and was known the old voyage as the
geenock Veins Of black oxide of copper have been open
ed Point Keweewenon that contain from sixy 10 seventy
per cent of copper Bluffs of conglomeraie trap dykes
ineseciing found la place between Agate harbor and
Eagle harbo with veins of cacarcous SPAR nterspersed
with daholiie and pieces of pure native copper these
have the evidences Of gneous origin the trap rock
There is also vein of phene four feet wide and every
CRYSTAL in which had crystal copper attached In
every vein that found opened in that region Ono matter
what the base less copper But the best
mine yet found the Eagle rivers the vein is from
to thirteen feet wde and the veins contain metallic cop
per and silver amygdy gobules, with crystals Of copper
pure silver in the gobue We also find leaf copper and
leaf silver and ocahedra crystals of silver DR. j. hercex
hbied fine specimens of all these minerals The great cop
rock found the Ontonagon had scpene attached
to il and the only copper find that is mixed up with
penne is Isle Royal whence thai great rock must have
been carried raft of ice, and landed above the RAPIDS
there is copper stu within miles Of where it found
In Nova Scotia the copper that is found just where the trap
through the sandstone and gneous action has probably
reduced the to native copper But the copper Lake
Superior confess think to have been part Of the primary
copper Of The globe, Gas Dr. Houghton also does brought up
from the molten by the trap rocks 1t is badly wrought
Stag if old Pluto had separated all the metal from the
Stag before he let the trap rock push for the service of
There is vein Of copper eleven feet wide and
mile long, that will reply all the outlay Of the company The
Cornish miners there have sunk four shafts the banks Of
the river intending TO work the mine under the river One
shaft already sixty feet another forty, another thirty feet
deepa done by hand power The deeper they the rich
the minerals and contains about fourth silver COL
Graot has the superintendent there. And in working
single exploration shaft at the Eagle River mine, the metallic
contents brought out by hand worth $780, 000 The rock
yoa and blasts very easily II does not take
than twenty minutes to make hole for blast There is no
the shafts all, although they have worked down
feet below the bed Of the river and instead Of the
of the river troubling them, when the dam built it
will be their greatest friend The water will raise the
from the mne pound it. blow the blast for the smelling fur
mace, and the wood for the buildings The prevailing
there the black oxide Of copper and the cae of cop
per there suphucts Of copper found in the whole
gion. One valuable large vein contains in the clean
twenty five per cent of "copper" besides ver and the deeper
they go the better il becomes.
DIR. Jackson warned people, however, against being
sanguina there wsu be good many poor mines opened
there and many bad spccuatons there in the
Maine timber lands. (Laushter.) The copper veins
easily found they south rs degrees west and wherever
find asne with the depression conformabe to that line
to find vein Of copper; wet place in
vine where the plants grow uxuany it is proof that sha
vein decays faster than the enclosing rock and that vein is
copper The best ux necessary to reduce copper ore is the
cacarcous SPAR and that is found in great abundance there
The great question il viii these copper veins hold out In
the West India copper mines the native copper changes to
suphures penetrate the mine The laws Of gravity are
vcr of the fact that the deeper the richer Will be
the vcn How shall down in the earth until we come
that spot where adle out the melted copper for
get how far Professor Roge.s said that would be.
Prof Rosers.--About ten miles !! (Laugher)
DR. Jackson.We have abundant proofs in specimens
that the copper and silver must have melted together we find
silver in the "copper" but find trace Of copper in the
silver We find also zszag veins Of silver running through
the copper. Now, if uy To make amalgam Of these
with it, part the silver viii unite with the copper and the
pure silver, ia mechanical with it
melt the silver and hiring the copper with IT, they
will thoroughly amalgamse And this singular segregation
find done by Nature in the copper veins Of the Lake SUI
peror region The plan proposed for separating the copper
and silver in these is TO make all the copper into blue
vto then make the silver chloride Of silver reduce IT,
and send TO the mint The copper will be broken up
at the mne carefully washed and picked aud then packed up
in kegs and sent down TO Boston be smeted. There il
also Of antimona silver found in these mines The
sandstone of this region has copper in il but the point
Of contact with the trap rocks there is little native copper
The rich vein Of black oxide Of copper opened at Fort Wi
kins Ia feet thick and contains 20 per ofcopper II
ton Of the rude asdeyercd by the miner at the pit banA
on Eagle river there is the following per ccntage
VI copper. W ~ t.tef
And In of the orc, delivered al Boston, there
s56s worth Of silver and $500 worth Of copper dat
il is properly silver mine than copper mie IL b.
olt, he If hor