History of the Carlin Trend (Elko Daily Free Press – May 1, 2015)

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CARLIN — On May 4, 1965, with little fanfare, Newmont poured its first bar of gold from the Carlin Mine. The pomp and circumstance of the official commissioning of the mine would have to wait a few more weeks. That first bar marked the start of one of the largest and longest-lived mining districts in the world.

In summer 1961, geologists John Livermore and Alan Coope arrived in Carlin to visit the Blue Star mine and the Gold Quarry prospect. Livermore had recently heard a talk by U.S. Geological Survey geologist Ralph Roberts about an area in northern Eureka County that had the potential for hosting gold deposits.

The type of deposit they were searching for was similar to Getchell, Gold Acres and Bootstrap, deposits in which the gold was dispersed as microscopic particles that could not be found using a gold pan. After visiting and examining the local deposits, Livermore and Coope began exploring an area approximately 2¾ miles south of Blue Star on Popovich Hill. They postulated that gold would be found in the limestone rocks below a regional fault known as the Roberts Mountains Thrust.

Drilling on the project began in 1962 and on the third hole intersected 100 feet of mineralization averaging 1.03 ounces of gold per ton, marking the discovery of what would become the Carlin Mine. Drilling to outline the orebody progressed quickly and by the end of 1963 had identified 11 million tons of ore averaging 0.300 ounces of gold per ton, a grade sufficient for mining when gold was selling for $35 per ounce. Construction of the mine and mill began in 1964.

Production ramped up quickly, peaking at 337,000 ounces in 1967 and delivering the millionth ounce in 1968. Between 1968 and 1980, production from Carlin began a slow decline, reaching a low in 1980 of 110,000 ounces — the same year that gold hit a high price of $800 per ounce. In 1971, the government had quit fixing the price of gold, allowing it to rise based on market conditions. This higher gold price allowed Newmont to acquire the Blue Star and Bootstrap mines in 1972.

Early mining in the Carlin pit focused on the oxide ore, all of which was fed to the Carlin Mill, now referred to as Mill No. 1. Early drilling, however, had shown that gold also occurred in refractory ore containing carbon, which had the undesired tendency to “rob” the gold particles out of the cyanide solution used to leach the oxide ore. In 1971, Newmont added a flash chlorination process to Mill No. 1 to treat the carbon-laden ore.

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