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The Lost Dupont Mine


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Rising up between the Rio Grande valley to the east and the San Juan Basin to the west, is a chain of rugged mountains that comprise one of the southernmost prongs of the Rocky Mountains. Part of the southern Rocky Mountain physiographic province, this chain of uplifted and buckled peaks extends for nearly a hundred miles through north-central New Mexico. Rising up from north to south are the Tusas Mountains, San Pedro Mountains, and Sierra Nacimientos.

This southern spur of the Rocky Mountains has been the scene of sporadic prospecting for over 200 years. Some areas were prospected during the early 1800's by Mexican miners. They discovered a few deposits including the "Copper City" site in the San Pedro Mountains (also known as the Gallina Mountains), near present-day Cuba, and the Rio Chama gold placers, located in the Abiquiu District.

A few areas may have been prospected during the 1700's by the early Spanish. A number of legends exist concerning lost Spanish gold mines in these mountains. The San Pedro Peaks region is said to harbor a hidden gold mine worked by Spanish miners.

During the 1880's, American prospectors swarmed into the area and made several strikes. The Abiquiu District was revisited as was the old "Copper City" site. A mining camp sprang up near the latter site complete with a 30-ton copper smelter. Sometime around 1880, rich placer deposits of gold were discovered in the Tusas Mountains, near Hopewell Lake. Nearly 10,000 ounces of gold were recovered from the gravels along Placer Creek, most of it during the first 3 years of operation.

In 1883, another discovery of gold was made in the San Pedro Mountains. Located some 60 miles southwest of Hopewell Lake, the deposit lies in the general vicinity of the lost Spanish mine of San Pedro Parks. The two deposits have much in common. Both are comprised of rich gold-bearing quartz and both are lost!

The 1883 discovery was made by two prospectors named Harris Dupont and F.D. Thompson. The two partners were working in the "Copper City" mines during the week and prospecting the San Pedro Mountains in their spare time. Eventually they stumbled on a rich deposit of gold-bearing quartz somewhere on the western flanks of the range. Some accounts place it near the San Pedro Parks area. Dupont and Thompson worked the deposit for some time, selling their ore in Cuba and Lagunitas. The partners came to a parting of the ways in 1884 when Thompson killed Harris Dupont and hid his body. Filled with remorse, Thompson abandoned the mine and left the mountains. Some say he returned to the San Pedros to rework the mine but was unable to find it. Like the lost Spanish mine of San Pedro Park, the Dupont Mine remains hidden today.


The history of mining in the southern Rocky Mountains of north-central New Mexico must surely begin with the early Spanish explorers and prospectors who penetrated the area in the 1700's. By the early 1800's, Mexican prospectors had replaced the Spaniards. The Mexicans discovered placer gold along the Rio Chama River near Abiquiu and copper deposits in the San Pedro Mountains, near present-day Cuba.

But it wasn't until the 1880's that serious mining began in the Tusas, San Pedro, and Nacimiento Mountains of New Mexico. Sometime around 1880, rich placer gold deposits were discovered in the

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Tusas Mountains, near Hopewell Lake. By 1910, the Hopewell District had produced over a quarter of a million dollars worth of gold, mostly from the gravels along Placer Creek. In 1881, the "Copper City" site was revisited by American prospectors who began to develop the rich copper and silver deposits first worked by Mexican miners years before. Eventually, over a million dollars worth of precious and base metals were extracted from the mines southeast of Cuba. The Rio Chama placers near Abiquiu were also reworked by American and Mexican prospectors during the 1880's.