The southern Arizona mining town of Bisbee once had more than 20,000 residents and in a century of mining produced some 8 billion — with a “b” — pounds of copper metal, but to many people, it’s best known for the few hundred tons of turquoise that were uncovered here in that last quarter century of mining.
This is a typical photo of Bisbee turquoise offered on eBay. It generally brings a premium price.
Bisbee turquoise was encountered in great quantities in the late 1950s and 1960s, about the same time that Arizona Highways magazine started publicizing the gemstone,which at the time was being set in silver by Navajo craftsmen. The fame of Native American jewelry and of Bisbee turquoise soon went worldwide, along with the magazine.
Because the best Bisbee turquoise was a deep blue, with a matrix of chocolate brown, it often was the gemstone of choice for Native craftsmen, and as their fame increased, so did that of the stone they were using. Good turquoise is relatively hard (6.5 on the Mohs scale, with talc being 1 and diamond being 10, vs. only 5.5 for lesser turquoise), it polishes to a brilliant, deep blue color and will maintain its color over a long period.
While some small quantity of turquoise were found in Bisbee underground mines, which began operation in 1880, it wasn’t until a major pocket of the material was hit in the Lavender open-pit mine in the mid-20th century that it was available in large enough quantities to become a commercial success, rivaling the best Persian for millennia past.
Bisbee’s copper was almost entirely mined by underground methods, with thousands of workers, around the clock, going each day deep into the bowels of the Mule Mountains, for the first 70 years of operations. A small surface operations was conducted as a break-even project in the 1920s, but it wasn’t until the early 1950s that a significant surface, or open-pit, operation got under way. It was named not for a color, but for the executive who engineered its development, Harrison Lavender. Bisbee mines also continued to be worked underground during that period.
Truckloads of turquoise
Large (by the standards of the day) haulage trucks, capable of carrying up to 65 tons of broken ore, or metal-containing rocks, were loaded by large electric shovels. They carried the low-grade ore to a crusher, where it was further reduced in size and fed into a concentrator, where grinding and chemicals made it possible to capture most of the metal. An ore concentrate was then shipped to a nearby smelter, where 2,000-degree temperatures melted the material, allowing the metals (which included gold and silver) to be separated from other less-valuable materials.
As mining progressed in the ever-deepening pit, it frequently encountered boulders of Bisbee turquoise, its beauty making it easy to pick out from the gray and brownish rock that hosted it. Miners frequently grabbed as much of the turquoise as they could and it left the jobsite with them.
Throughout the history of the mines, the company had a policy of letting miners take away whatever attractive minerals they could find. (That is fortunate, became many of those “rocks” are today’s fine museum-quality minerals and show the beauty of Bisbee to the entire world.)
And Bisbee offered lots of minerals. With more than 330 species of minerals found in the Bisbee mines, it’s one of the richest, most diverse ore bodies in the world. (Some of that mineral diversity can be seen today at the Bisbee Mining & Historical Museum, which hosts an extensive exhibit developed in affiliation with the Smithsonian Institution.)
The mining company eventually halted the collection of Bisbee turquoise because some miners were taking great safety risks to get to it.
Today many jewelers in Bisbee actively seek local turquoise from families of miners who collected it decades ago. One company, Bisbee Blue, has the rights to mine turquoise from the old dumps and offers local material, set by Native American silversmiths, at its store at the Lavender Pit viewpoint.
Bisbee turquoise is a souvenir of local mining heritage that a visitor to the historic mining camp can take home and be proud to show off for years to come.
Loading ...