New Mexico Mineral Symposium — Abstracts

The first road to traverse the continental United States from the east coast to the west coast was the Lincoln Highway. Conceived in 1911 and dedicated in 1913, it stretched across 13 states from Times Square in New York City to Lincoln Park in San Francisco. But the first paved road was Route 66, also known by such colorful names as the Will Rogers Highway, the Mother Road, and Main Street America. Route 66's eastern end was in downtown Chicago, with its western terminus in Los Angeles. Completed in 1938, Route 66 not only provided a relatively smooth ride for motorized vehicles, it was also a means for migrant workers of the 1930s Dust Bowl era to safely travel west in search of better lives.

Our mineralogical journey along Route 66 will start at the western end just east of where the Arizona and California state lines meet and end in the east before crossing into New Mexico on Route 40. First to consider are the mines and minerals in the mountains and canyons surrounding Oatman. The Oatman mining district in the Black Mountains is also known as the San Francisco and Union Pass districts. Of note is the Moss mine. In 1863 it was the first located in the district, and also the first and oldest patented claim in Arizona. The Moss was followed shortly thereafter by the Hardy and the Homestake. The district is known for lode gold, which occurs in quartz-monzonite porphyry veins. Mining will resume at the Moss mine through the efforts of current owners, Patriot Gold Corporation of Canada. In February 2013, the company announced a three-phase operation on the property. The open pit, heap leach operation is scheduled to begin commercial production of gold by mid-2014 and continue through 2017.

Mining at the Hardy and Homestake mines began in the mid- to late-1800s and continued to the 1920s. Of late, these mines and other claims in the Oatman district are most notable for occurrences of green fluorite.

Gold Road joins the Moss mine as another lode gold occurrence in the Oatman district. It produced intermittently from 1902 to 1949. Gold and silver with trace beryllium occur in a vein in Tertiary volcanics. Current owners conduct public tours of the mine. Other tourist attractions along the western beginnings of Arizona’s Route 66 include historic Oatman. Oatman started as a gold mining camp in 1906. Centrally located in the Oatman mining district on the western flanks of the Black Mountains, the town served as a supply distribution point for mines in the area and residential area for its burgeoning population. At its peak, Oatman had a population of nearly 3,500. Currently, the town’s permanent residents number about 150. The town caters to tourists traveling historic Route 66 and those seeking some of the early mining history of northwestern Arizona. Nearby Bullhead City, Arizona, and Laughlin, Nevada, along the Colorado River, are also places of interest for visitors to the area.

The next localities of note are north of Kingman, and a side trip in that direction takes one first to the mines and copper minerals found at Mineral Park. Mineral Park is considered the oldest camp/town in Arizona. The post office operated from 1872 to 1912.

Copper was the first mineral of choice mined at Mineral Park, but silver, gold, molybdenum, and lead were also recovered from the Precambrian crystalline rocks. Mining peaked between 1876 and 1892. Modern open pit mining began with Duval in 1963, followed by Cyprus in 1986, and Equatorial Mining of Australia in 1997. In 2003, Canada’s Mercator Minerals, LTD. acquired the property from Equatorial. In 2012, Mercator announced that the ore reserves provided for a 22-year mine life.

Continuing north of Mineral Park and one comes to Chloride, the oldest continuously inhabited town in Arizona. It was originally a silver camp founded in 1863 but mining in the area did not commence until the 1870s, even though mineral resources were first located in the 1840s.

And finally, the northernmost mineral locality to consider is in Gold Basin east of Highway 93. Wulfenite, vanadinite, and mottramite with micro gold crystals occur at several of the mines in the area. Gold Basin is also the site of a meteorite fall and numerous specimens of the nickel/iron meteorite can still be found in scattered localities.

The longest and best-preserved sections of the original Route 66 stretch easterly out of Kingman and at Ash Fork, it lies under Interstate 40. But at Flagstaff, we will take another mineralogical jaunt north to the Grand Canyon. While the Grand Canyon is a bit off the beaten track, trappers, prospectors, and miners were drawn to the canyon area in the mid- to late-1800s. In the late 1880s, John Hance attempted to mine asbestos in the canyon. Louis Boucher, who arrived in northern Arizona and the Grand Canyon about 1889, mined copper until 1912. And in the 1890s to early 1900s, Ralph Cameron opposed the Grand Canyon’s national park consideration in an attempt to open a platinum mine near the south rim. Some notable mines on the South Rim include the Cameron, the Grand View, and the (Old) Orphan. A recent contribution to Arizona’s type mineral specimens, grandviewite, was discovered at the Grand View mine.

One cannot leave the Grand Canyon without a nod to John Wesley Powell. He was the first to traverse the Grand Canyon by way of the Colorado River in 1869. During his tenure at the Smithsonian in Washington, D.C., he led three river expeditions through the Grand Canyon. Powell served as director of the U.S. Geological Survey from 1881 to 1894.

We pick up Route 66 once again at Flagstaff where it continues to underlie I-40. East of Winslow and south of I-40 is Barringer Crater. Also known as Meteor Crater and Canyon Diablo, it was named after Daniel Barringer, who was the first to recognize it as a meteor impact. About 50 thousand years old, the impact formed in Pleistocene rocks. The crater is 4,000 feet in diameter, 570 feet deep, with a 150-foot rim. In 1903, Standard Iron Company staked claims on 640 acres around the center of the crater, estimating iron reserves up to 100 million tons. While the mining operation did not progress as hoped, remnants of the nickel/iron meteorite have made their way into collections worldwide.

Route 66, still underlying I-40, forms the boundary between the Painted Desert in the north, and Petrified Forest in the south. Petrified Forest is about 146 square miles. It was named a national monument in 1906 and a national park in 1962. The rocks of Petrified Forest, the Chinle Formation, are about 225 million years old. Nine different species of trees, all extinct, have been identified at Petrified Forest, but the most common are of the species Araucarioxylon arizonacum, Woodworthia arizonica, and Schilderia adamanica. Other fossil flora includes ferns, cycads, and gingkoes. Phytosaurs (fossil crocodiles), Buttneria(fossil amphibians), and early dinosaurs have also been found along with the fossilized flora. Silica, in the form of agates with some crystallized quartz permeated the fallen trees, the result of volcanic eruptions, thus preserving them in the form of petrified wood. Iron, manganese, and copper stained the silica in some instances resulting in the rainbow of colors in the fossilized wood.

Painted Desert lies at the southern end of Monument Valley. It gets its name from early Spanish colonialists who called it El Desierto Pintado. The rocks are siltstones, mudstones, and shales of the Triassic age Chinle Formation, the same rocks that occur in Petrified Forest. Iron and manganese stain the rocks various hues that give the Painted Desert its name. This approximately 7,500-square-mile area was named a national landmark in 1906, and later raised to national park status. Mineralization and fossilization in the Painted Desert are similar to that found in Petrified Forest.

As we approach the eastern boundary of northern Arizona at the New Mexico line, the original Route 66 is broken into bits and pieces in the populated areas off I-40. But a few miles remain under the interstate. So our last look at mineralization will be to the north in Monument Valley on the Navajo Indian Reservation. The Navajo call Monument Valley Tse Bii’ Ndzisgaii or Valley of the Rocks. Buttes, very popular in early western movies out of Hollywood, rise about 1,000 feet off the valley floor. The rocks are shales and sandstones stained with iron oxide. From 1948 to 1967 mining activities in Monument Valley recovered uranium, copper, and vanadium.