The Arizona sentinel. [volume] (Arizona City [Yuma], Yuma County, A.T. [Ariz.]) 1872-1911, 1879-03-01
silver District.

forming high opinion of its future i'm
pOrtance and productiveness. We found
its characteristics greatly exaggerated in
some respects, and equally moderated in
others. The main ore-channel extends
for several miles, its groupings marked
by a striking uniformity in appearance
and material On the west side the
country rock appears to be protOgine or
talcose granite: on the east the formation
is essentially volcanic; basalt, lava and
scorie forming its hills, and in many
places everything the ore-veins. This ore
channel has the position of continual
ton of the mineral belt running through
the old Eureka District; but its gangue
and the composition of its ores mark it az
something different and distinct. At the
southern end of the ore channel are the
huge groupings of the Black Rock and
Pacific, forming tie southern, eastern
and northern sides of q great basin cut
| through by an arroyo or wash; while the
Engineer groupings form its western wall.
This basin is shaped somewhat like the
oblong crater of volcano, cut through on
two sides by some stream. On either side
of it the ore stands up, to heights reach
ing 100 feet and upwards, of thickness not
yet determined, though exposed in places
to width of ten to thirty feet. This huge
mass extends for nearly 5000 feet on the
two mines first named; and must COM
rrise several thousands of tons of ore
good enough to pay for reduction. Its
general character can only be determined
by breaking open boulders that have
rolled down from it, and from Inspection
of the small openings that have been
made into it. While nearly all of it yields
an appreciate assay in silver and lead, at
| least half of it is practically barren. The
richer ores are scattered in kidneys and
tortuous seams throughout the great
mass of spar and quartz. These ores are
chiefly lead-sulphates mot galena) rich in
silver Their great specific gravity indi-
Gates stamping and concentration by cur
rents OF water as their proper treatment
prior to reduction. At present the better
ores are laboriously separated from the
poorer ones by hand, and then shipped to
San Francisco for sale. The only ship
ment yet sold from this Ore-channul,
yielded over 800 ounces Of silver per ton
and about 50 per cent. lead; this ore was
| not well separated from its adherIng
ganguc. North from this basin the country
| is more covered with detritus; though the
ore-vein projects in nearly continuous
chain OF hills and reefs. In the Red
Cloud location the ore lies against a steep
hill rising to a height Of thirty or forty
| feet It is covered with crust Of earthly
and lime silicates, ranging from few
/ inches to few feet in thickness. This
crust has been stripped off from a. surface
eight or ten feet high and twice as long,
exposing a massive body Of ore, from
which were stripped ten or twelve tons,
forming the shipment already mentioned.
No attempt has yet been made to deter
mine the thickness of this Ore-bodyi but
from appearance Of the groupings it can
not well be guessed at less than ten, and
it may reach thirty feet. The ore is of the
same description as that of the Pacific and
| Black Rock, though more concentrated.
The peculiar crust of the groupings is
easily followed for several miles, over the
Nellie Kenyon, Friend and other loca-
tions; through the rugged heights of the
Rover, and to the lronsides. Here the
ore-channel rises higher, and in the Iron
sides are found more marked indications
of ali east wall, as well as the spar and
kidneys of ore of the other locations.
Excellent assays have been obtained from
this mine, and in many respects it prom
ises to equal anything yet found in the
District. In the Los Pilares, a mile
farther north, an body is being strip
ped which is said to rival that Of the Red
Cloud Rich samples have been brought
in from claims located one and two miles
still farther north, and which we had not
time to visit. At each side of the main
ore-vein are other locations on the same
channel, from which good ore is being
taken and high assays made. A late as
say from the Silver Glance gave 5,963
ounces silver per ton. Ore from the Iron
Cap gave S3S ounces. Ore from the En-
gineer is said to have given over $4,000
per ton. While these assays are undoubt-
edly exceptional, they are OF much value
in giving encouragement to miners and
prospectors. The present ores of this
District require concentration and smelt-
ing. But several intelligent experts have
expressed the opinion that they will be
found to be milling ores, of $50 to $3.50 per
ton, at no considerable depth. The note
worthy features of these new mines are
the massive character Of their groupings,
the general occurrence of metal in them,
the great length Of the Ore-channel on
which they are located, and its unusual
, breadth. The formation is pronounced
favorable to the permanence of ore de-
posts at any attainable depth.
These mines lie 81 miles north Of Yuma