The copper era and Morenci leader. [volume] (Clifton, Ariz.) 1911-1929, 1920-01-30
HISTORY OF THE AJO
COPPER MINING
DISTRICT.
An Interesting and illustrated Pamph.
let On The District Which Lays
Claim To Being The First Of
The Southwest
(By E. Jacobs)

+ Inc following is the Introductory
History of the Ajo District printed
in an illustrated pamphlet on the
Property, Plant, and process of the
New Cornelia Copper Company, which
pamphlet was distributed gratuitousIy
among those who attended the meet
ing of the Arizona Section of the Am
rican Institute of Mining and Metal
lurgical Engineers held at Ajo on Jan.
8 and g. 1t was reprinted from a con-
tribution by Ira B. Jeralemon to the
A. l. M. E. Transactions, Vol XIX,
1914, entitled "The Ajo Copper Min
ing District"
''The Ajo, next to Santa Rita, New
Mexico, is >claimed to have been the
first copper district in the Southwest
worked by Americans In the sixties
or even earlier, high-grade native
copper and cuprite ore was mined
from shallow surface workings and
hauled by bull-teams 400 miles across
the desert to San Diego, California
From there it was carried in sailing
ships to Swansea, Wales Later, the
ore was hauled to Yuma, fioated down
the Colorado river to the Gulf of Cal
ifornia and shipped to Swansea But
| infested old workings and the mas
sive axles of the bull-carts are shown
to prove the truth of the stories.
hi vi ird Jna In
ginning of the present century the
Ajo district was worked in casual
and intermittent way. With the in
creased interest in copper mining dur
ing the past decade, the brilliant sur
ee-@showing at Ajo furnihsed an
ideal basis for stock companies. A
succession of reorganizations and
new stock issues resulted in little un-
derground development, and the great
est depth reached in the two or three
years of activity was hardly more
than 100 feet. Rich bornite and chal-
cocite ore was shipped from several
small veins, and stamp mills with
concentrators tables were installed to
treat lower-grade ores. But the long
dry haul to the railroad made the
shipment even of rich ore and concen-
trates hardly profitable. In an effort
one of the companies fell a prey to
the promoters of patent processes.
The McGann vacuum smelter and
complicated hydromuoric acid teaching
plant still stand as monuments to the
hopes of disappointed stockholders.
The end of this period in the life of
the district came with the panic of
1907, when the final products of the
reorganizations-the New Cornelia
Copper Company, and the Kendall Ore
Reduction Company-were forced to
close down.
The Ajo camp enjoyed shOrt-iived
boom in the winter of 1909-1910. The
on the New Cornelia Copper Com
pany, and Seeley w. Mudd and asso-
ciates optioned the Kendall Ore Re-
duction Company. Demonstrating
| and underground work were started
on the New Cornelia property, and
churn drilling and underground work
on the Kendall. Many engineers
| came to examine or buy smaller pro-
| perties, and claims were located for
miles in all directions. Since the
drilling did not give satisfactory re-
suits, both options were soon given
up. The camp returned to a NOR
bid condition, and until the Fall of
1911 no work was carried on save for
a little leasing on small high-grade
surface veins
Nearly all of this early work was
in the lower ground surrounding the
hard silicified outcrope of Copper
mountain A few shallow holes on
Copper mountain had developed low
grade, very siliceous malachite ore,
and three or four deeper holes had
penetrated below the carbonate zone
to a disseminated chalcopyrite and
bornite ore assaying from to 4 per
cent copper. Both the carbonate and
sulphide ores were so unusual in
character that it was doubtful if they
could be treated with profit by pro-
cesses in common use even if large
ore bodies existed.
'In the fall of 1911 the Calumet E.