Each February I try and return to Tucson, Arizona,
for the gem and mineral show (see numerous Blog postings) as well as to explore
the surrounding countryside. Of course,
one of the more interesting geological localities is the Santa Catalina
Mountains, the skyline-dominating range of north Tucson and Oro Valley. There are very few roads heading into the
western front and most travel is by foot.
However, the north end, and the “backside,” of the range have several
trails and roads to explore by using the small community of Oracle as a
base. The major road from Oracle heading directly
into the interior of the Range is known as the “Control Road” and leads to Mt.
Lemmon and the summer housing community of Summerhaven. However, there are many smaller roads weaving
in and out of the Range flanks and any traveler should obtain a good Forest
Service map and/or topographic map.
These maps, besides showing the roads and trails, delineate the parcels
of private land that are scattered throughout.
The Santa Catalinas have produced metallic ores such
as gold, silver and copper; however, the Range has not yielded the huge
deposits as at other nearby Arizona localities---for example, the Tiger/Mammoth/St. Anthony
mines to the northeast and their deposits of gold, molybdenum, vanadium, lead
and zinc and the San Manual copper deposits to the east.
It is not that gold is absent from the Catalinas for there have been
several local “gold rushes” in the area, mostly around Oracle and the
“backside” of the Range, but the yields generally have been low. Mines were first staked and claimed in ~1880
and a geologist told me that perhaps 70-80 (or more) claims were posted close
to Oracle. He also informed me that
shafts and holes are quite numerous but that many entrances are located on private
property. This trip I talked to some of
the local residents and it appears that every year “some company” is about to
reopen a gold mine, and plans on a big operation. This “reopening” may be happening in the near
future but the end product will be copper.
For several years Oracle Ridge Copper has been in the planning stages to
reopen the Oracle Ridge mine located on the backside of the Range west of San Manual. A February 2014 news release noted that core drilling
and evaluation indicated the feasibility of producing substantial amounts of
copper with some silver and less gold.
The company is progressing toward active mining.
The geology around Oracle is fairly complex---a big
hunk of the Oracle Granite of Precambrian age (~1.4 Ga) with Tertiary intrusions
and volcanics, much faulting, and evidently some Paleozoic limestones. It is tough to find out much about the
geology of the mining area but it seems as though the mineralization is related
to faulting and I suppose hydrothermal alteration. Interesting Cenozoic
features include the bajadas sloping off the range in all directions. They form
as alluvial fans accumulate sediments at the mouths of canyons, and then with time
these fans increase in size and coalesce into bajadas. The second feature to appear in the area are boulder inselbergs, small hills of fractured granite arising from the
bajadas. An inselberg is an isolated “hill”
and the Oracle inselbergs are in-place rounded boulders of the granite
dissected by numerous joints.
So, during my road trip I was driving around on the
various minor country roads looking at the rocks and trying to decide if I
wanted to explore since it appeared that much of the land was private/claimed. I was also sort of spooked since I did not
have on my gators and a couple of days before had seen a quite large
rattlesnake. I was hiking down a trail,
minding my own business, and had adopted the geology stroll---keeping your eyes
on the ground. All of a sudden I stopped
in my tracks after hearing a big buzzzzzzz, a sound that hikers and geologists never
forget. There it was, about 8-10 feet
down the trail, coiled and unhappy that I had disturbed his nap in the
sun. I tossed a couple of small rocks in
his direction, said something like “shoo snake”, and waited. Those actions only
ticked him off and made him really mad. I wisely decided that discretion is the better part of valor and took a wide detour.
In searching references it appears that many, many
stories are out there about the gold and other metallic ores near Oracle. Perhaps the most interesting are those associated
with William “Buffalo Bill” Cody. In a 1910
article in the Los Angles Times, BUFFALO BILL BEGINS MINING IN ARIZONA
Veteran Scout and Showman Takes Up New Life with Old Comrades: In partnership with his old cronies, John
Burgess, scout and prospector, and Colonel L. W. Getchell, mining engineer,
Colonel W. F. Cody has started to develop 100 claims in southeastern Arizona
(2000 acres) about 40 miles north of Tucson….The Cody-Getchell-Burges syndicate
has turned six claims at Campo Bonito [near Oracle] into a $600,000 corporation under the
style and title of the Campo Bonlto Mining and Milling company, and the first
development work will be made there.
The
mines at Campo Bonito contain gold, silver and tungsten and surface workings
yield about $30 a ton The ore runs nearly 3 per cent tungsten [mining scheelite], a mineral which
has come Into large use In the hardening of steel and in the manufacture of
lamps…Colonel Cody carries in his pocket a nugget of pure gold taken from one
of the Campo Bonito claims that is worth about $60, and he shows it with great
pride, says a New York exchange.
Mr. Robert Zucker Tucson, Arizona native, author,
former journalism instructor and newspaper publisher, is the CEO of Entertainment Magazine network, publisher of AZentertain.com. Zucker has researched and
explored the Santa Catalina Mountains and has written a number of articles on
the history of Oracle and the nearby mining districts. See http://azentertain.com/arizonagoldrush/
for other articles. In addition, a local
prospector, William “Flint” Carter, mines “Cody Stone” (gold in quartz) that the
lapidary then turns into design jewelry and cabs. Check out: http://emol.org/irondoor/codystone.html.
All in all, it was a good day. It had been a number
of years since I had visited Tiger/Mammoth so that was nice; however, a poor
ole traveler like me could not get near the actual mine (appears mostly
reclaimed). I did not locate the “lost” Iron Door Mine but did get to observe,
rather closely, a splendid Western Diamond Rattlesnake (Crotalus atrox). And in the evening the Arizona sunsets (with some dust and pollen in the air) are spectacular, just like the gold. Life is
good.