100 Years of Arizona’s Best: The Minerals that Made the State
- Historic Mining Towns
- Arizona's Mineral History
- The Union Struggle
- Bisbee’s Crystal Caves
- Tucson Gem and Mineral Society
Before air conditioning turned Arizona into a “sun belt” destination, life in the rugged remote desert was difficult. Heat and drought drove many early settlers and ranchers to ruin. But dreams of mineral wealth lured prospectors, then miners, to brave the heat, thirst, and Apache attacks so they could stake claims and dig for precious metals.
The discovery of large silver deposits around Globe, Superior, and Tombstone drew thousands of fortune seekers to the territory in the 1870s and 1880s.
Just as some silver deposits were drying up in the 1880s, a bonanza of copper discoveries started mines that built towns, railroads, and fortunes around the state. More than any other resource it was copper, and the workers that came to mine it, that pushed Arizona to become the 48th state, the last of the contiguous United States, in 1912.
Many of the wondrous colors and forms of Arizona minerals developed from the chemistry of copper. As soon as discoveries were made in the late 1800s, Arizona specimens attracted wealthy collectors and thrilled visitors at the World’s Columbian Exposition in Chicago in 1893, and the St. Louis World’s Fair in 1904.
Featured Exhibit: The Minerals that Made the State
Historic Mining Towns
Mines and miners built many of the towns in Arizona. Some of the mines are still producing, and the towns have survived with them. But most of the mines closed when the ore gave out, then the jobs vanished and the people left, leaving only ghost towns.
Some towns where the mines closed were able to attract tourists or retirees and survive as Arizona's economy shifted from extraction to attraction. No matter where they stand today, all these towns are on the map thanks to the metal in the ground and the jobs the mines provided.
Arizona’s Mineral History
The unique geology of Arizona not only gives the state some of the most gorgeous vistas in the nation, it also gave the state its copper riches.
Copper Formation: A Scientific Mystery
In the language of geologists, the “Copper Province” of the American Southwest, centered on Arizona, has few counterparts in the world, and none in North America. These deposits are called Porphyry Copper Deposits because they appear in a type of rock called “porphyries.” More than a century of mining and discovery in this region, and a century of geological study, have yet to provide a conclusive answer about the reasons for this unusual concentration of the red metal. However, geologists continue to grow and refine our understanding of the geology and origin or Arizona’s copper deposits.
UA Expert on the Case
Dr. Spencer Titley, Professor Emeritus in the UA Department of Geosciences, has spent his career trying to answer the geologic mystery of Arizona’s copper deposits. He explains what we know like this: most of the deposits formed in a narrow interval of geologic time, between 60 and 65 million years ago. They formed along a continental margin during a period when, in terms of plate tectonics, oceanic and continental plates were converging rapidly, and they are closely related to ancient volcanoes.
Previously, geologists believed that the copper came from the mantle (a hot layer of rock below the Earth’s surface crust), and mid-century ideas involved rock from the ocean crust. However, evidence from Dr. Titley’s research using isotope analysis now reveals that there is a significant contribution to the deposits from local rocks in the Earth’s crust, and that evidence points to a different, yet still uncertain, origin story.
The final story remains to be discovered. But we know that it took millions of years of geologic transformation to create Arizona’s great copper wealth, a resource that humans have mined for about 140 years.
Many of the same geologic forces that created copper ore deposits created the wondrous mineral specimens that we see in this exhibit. Water, heat, pressure, and minerals combined over millions of years to form incredible colors and crystals when chemical elements met the right conditions. Most of the minerals formed in regions where water and air from the surface could seep in.
In much of North and South America, this surface zone was scraped bare by glaciers during the last ice age, a mere 15,000 years ago, so whatever mineral specimens formed were destroyed, but the glaciers did not reach Arizona. Arizona’s underground copper mines were also crucial to the discovery of many amazing Arizona mineral specimens—if miners had not gone deep underground to dig copper ore, many of these incredible specimens would never have been discovered.
The Union Struggle
Although few Arizona mines are still unionized, the struggle between labor and management is a central part of the story of copper in Arizona.
The Fight for Equal Pay
Underground mining was a tough job, but it paid well. Skilled miners could make a good living, and most of them loved the camaraderie underground. But in many Arizona mines from the 1880s up through the 1940s, Mexican-American miners were paid at a lower wage scale than Anglo miners. In addition to the push for better pay, benefits, and improved safety conditions, it was this wage disparity that drove miners to organize. After Mexican-Americans returned from fighting in World War II, they refused to accept second-class status. Miners soon won equal pay, and all the mines in Arizona were unionized.
The Bisbee Deportation
On July 12, 1917, nearly 1200 Industrial Workers of the World (IWW) strikers were rounded up and deported from Bisbee by county officials and citizen posses. Strikers were held at the ballpark in Bisbee until a special train of 24 cattle cars arrived from Douglas to pick them up. Over the next 16 hours, they were transported 200 miles through the desert without food or water. The deportees were unloaded at Hermanas, New Mexico, without money or transportation, and were warned not to return to Bisbee.
The Union Era
Starting in the mid 1940s and for roughly forty years, Arizona copper companies negotiated conditions and contracts with the International Union of Mine Mill and Smelter Workers (IUMMSW), and most contracts lasted three years. At the end of three years, new contracts were sometimes resolved quickly and other times they prompted strikes that dragged on for months. The strength of the unions was finally broken in the infamous 1983 strike, most visibly in Morenci, when copper giant Phelps Dodge purged the unions from its mines. It was a turning point in the history of the United States labor movement.
San Manuel Success Story
The giant San Manuel underground mine north of Tucson remained a union mine, but relations between management and labor deteriorated until 1991 when the company hired consultants who brought the two sides together. The workers and management developed trust, and the company engaged employees in mine design and decisions. The new solidarity resulted in an unprecedented ten year contract and astonishing gains in productivity that made headlines in the business world.
Can you find all eight miners in the cave photo?
Pull the bar back and forth to compare.
Bisbee’s Crystal Caves
Imagine the dim, grimy, back-breaking labor of an underground miner in the late 1800s.
Your only light source is a candle, and your eyes have adjusted to the gloom. When the smoke clears from the last dynamite blast, you see an opening in the solid rock ahead of you. You stick your candle into the crevice and peer inside. A vast and wondrous cavern opens in the flickering light—one of Bisbee’s magnificent crystal caves. Crystalline white stalactites hang from above, the walls molded in rich blues and greens of azurite and malachite, it is a sight to inspire fables.
Alas, most of the caves were destroyed as the miners removed the rich copper ore around them, and the caves that survived are no longer accessible, but some of the gorgeous mineral specimens from the caves still inspire awe.
Tucson Gem and Mineral Society
Arizona has been blessed with an abundance of copper, and its amazing mineral specimens rank among the best anywhere. Yet Arizona’s minerals and the passions they inspire would not have captivated millions and nurtured the greatest gathering of gem and mineral collectors in the world if not for the Tucson Gem and Mineral Society, a non-profit, wholly volunteer organization. When the Society began in 1946 as a local association of rockhounds, collectors, and mineral professionals, the members just wanted to share their excitement, their specimens, and their stories. They had no notion of how they would inspire and unite an international audience of mineral collectors. The first “Tucson Gem and Mineral Show,” organized by the Society in 1955, was a humble affair hosted at an elementary school—and it was a hit from the very beginning.
Over the years the show grew to become the first and largest international showcase for gems, rocks, and minerals in the world, a gathering where the best gems and minerals come together with the knowledge and passion of top collectors and dealers from around the globe. The contribution of the Tucson Gem and Mineral Society to the study, appreciation, and popularity of minerals is profound, and it all started in Tucson, Arizona.