Turquoise Hill: a Profile of the Cerrillos Turquoise Mines
Turquoise Hill in New Mexico is the oldest turquoise mine in North America. Learn the history of this amazing site and tour it through photos.
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Where is Turquoise Hill?
Turquoise Hill sits within an 80-acre patch of land owned by Douglas Magnus. A highly respected silversmith and jeweler, he helped design and construct the official gavel of the State of New Mexico. Oddly enough, my discussions with him and his wife, Wendy, revealed an unexpected personal connection. Decades ago, to my mother's dismay, my grandfather would drop in at Douglas' showroom before heading to our home from the airport!
Douglas acquired the land in the 1980s, a purchase prompted by his love of the native gemstone. Turquoise permeates this patch of land, which holds six turquoise mines, all now considered commercially mined out. However, this doesn't mean the land has no treasures left. Vibrant blue and green turquoise pieces cover the ground, and Douglas and Wendy collect them by hand. Douglas sets this turquoise in his hand-made silver items without introducing additives or treatments to the gem. He donates all extra inventory to the Native American descendants of the original miners, members of the modern-day Kewa Pueblo (previously known as the Santo Domingo Pueblo), for their jewelry designs.
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This article is also a part of our Turquoise Specialist Mini Course, in the unit Introduction to Turquoise.
The Millennium Mine
Wendy met me at Turquoise Hill on a brisk December day. An expert on the land and its long history, she said the most ancient of the Turquoise Hill mines has known several names. Many locals call it the "Tiffany Mine" out of habit. In the later part of the 19th and early 20th centuries, the owners sent its beautiful blue and matrix-free turquoise to Tiffany & Co. in New York. However, the mine itself has no affiliation with Tiffany & Co. Thus, Douglas renamed it the "Millennium Mine" to eliminate any confusion.
Native American Mining at Turquoise Hill
Wendy began our private tour by explaining the deep history of the land. The Native Americans have been mining turquoise here for at least the last thousand years and consider the ground sacred. Using only handheld hammers and chisels, they cut down into the turquoise-rich volcanic mafic rhyolite rock. It's impossible to know the exact depth of the original mine as the Native Americans filled in their shafts with tightly pressed soil, but it's at least 50 ft. Some estimates say it may have been more than twice that deep.
Having personally excavated one of these repacked shafts, Douglas describes how the Native Americans clearly took great care to accomplish this. He found ancient mining tools placed around the perimeter of the shaft. They considered this place so holy that they buried some individuals here with their tools. The interred were likely affiliated with the mine.
Into the Mine
The Native American workers mined this land by cutting directly into the turquoise deposit. They created a deep pit accessible only from the top. As the mine grew deeper, they placed sturdy logs horizontally across the shaft.
Spanish Mining at Turquoise Hill
Unfortunately, a detailed history of mining activity through the centuries is impossible to reconstruct since Native Americans didn't leave behind any written records. However, Douglas says evidence indicates the mine was used throughout the 14th century CE. By the time the Spaniards arrived in the mid-16th century, mining had apparently ceased, and the shafts were filled. While the original shafts were blocked, the knowledge that this land held turquoise was never lost. The Spaniards made their own, albeit somewhat clumsy, attempts to extract turquoise here.
James McNulty and Turquoise Hill
The story then jumps to the early 1890s, when James Patrick McNulty became the manager and supervisor of the American Turquoise Company holdings located just north of Los Cerrillos, New Mexico. This location included Turquoise Hill. Wendy gifted me Tiffany Blue, a book recounting McNulty's activities written by Patricia McGraw, McNulty's great-granddaughter. McNulty brought modern mining techniques, specifically dynamite, which he used to blast into the existing Native American shafts from the side. By cutting in horizontally, he eliminated the difficult task of hauling the heavy product vertically. Mr. McNulty deepened the mine to approximately 200 ft.
Cerillos Turquoise and Tiffany & Co.
During this time, McNulty sent the best pure blue material from Turquoise Hill to Tiffany & Co. in New York. In fact, the glowing assessment of this turquoise by the famous George F. Kunz, one of Tiffany's expert gemologists, helped popularize "Cerrillos turquoise," as the turquoise from the Los Cerrillos region came to be known. These gems gained the reputation of being among the most beautiful turquoise in the world. Tiffany & Co. bought all the Turquoise Hill inventory. The turquoise-blue color of Tiffany's packaging, still used today, reflects the influence of the turquoise from this place.
McNulty successfully mined the deposit until 1933. However, Wendy explains that he and his men left behind a lot of green turquoise with dark matrix. Although not valued then, this darker variety now has its connoisseurs.
More Mines at Turquoise Hill
Currently, none of the mines on Turquoise Hill can operate on a large scale. Thus, for safety reasons, fences seal off their entrances. The Millennium Mine now has two separate entrances that no longer connect underground. Just a few hundred yards from the Millennium, you can find the Upper and Lower Castilian mines as well as another known as the Alicia.
Roads Paved with Turquoise
As Wendy and I hiked back to our cars after a two-hour excursion, she pointed out various large mounds of broken and crushed rock scattered around the property. She asked if I could guess what they were. My first thought was that they were waste from the mining activity. She laughed and said that there was a much more amusing explanation.
At one point in the early 1980s, the state began to improve rural roads. To minimize construction costs, they used whatever local rock they could scavenge. One day, the previous landowners returned to find a pristine, brand-new, seven-mile stretch of road paved with their turquoise-bearing stone! Naturally, they were quite miffed that the state used their stone, which contained salable gems and historically significant artifacts. They demanded that the state dismantle the roads and return all the material. This is the origin of the piles.
Emily Frontiere is a GIA Graduate Gemologist. She is particularly experienced working with estate/antique jewelry.
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