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The Lost Diamond Mine of the McCullough Mountains


The year was 1872. It was the year of the Great Diamond Hoax and the beginning of the end for one of the most powerful men in California. William C. Ralston, financial wizard and head of the prestigious Bank of California would see his empire collapse around him as a result of the Great Diamond Hoax. Ralston was only one of several prominent men duped by the two con artists, John Slack and Philip Arnold. By the time it was over, a number of fortunes had been lost, the reputations of a geologist and famous jeweler had been compromised, and William C. Ralston would be dead of an apparent suicide.

It all started when two prospectors named Philip Arnold and John Slack showed up at Ralston's bank with a sack full diamonds and rubies. The stones seemed to be real enough. They were appraised by the famous Charles Lewis Tiffany at $150,000! Arnold and Slack told the banker they had discovered a fabulous gem deposit near a small mountain along the Colorado/Wyoming border. Ralston's interest was piqued, but his suspicions were aroused when the two miners offered to sell him their mine. Ralston hired a geologist named Henry Janin to investigate the deposit and he pronounced it both rich and genuine. As a result of Tiffany's appraisal and Janin's geologic assessment, Arnold and Slack collected $660,000 from various investors. They then promptly disappeared. Meanwhile, it was soon discovered that the stones were actually inferior-grade and nearly worthless. Worse still, the deposit itself was suspect. It turned out that Arnold and Slack had salted the mountainside with cheap, industrial-grade African diamonds and flawed Burmese rubies. When the bubble finally burst, Ralston's bank closed down and he apparently committed suicide.

A number of geologists and mining men had looked on with dismay and amusement at the antics of Ralston and his cronies. They could have told him there were no diamonds in Colorado.

Everybody knew that. But then the Stateline kimberlites were discovered in the mountains near the Colorado/Wyoming border. Since its discovery in 1986, the famous Kelsey Lake kimberlite has produced many gem-quality diamonds, some of them up to 28 carats in size!

The state of Nevada has always been mining country. It is one of the world's great repositories of gold, silver, and copper. Nearly every mountain range in the state is home to some mining district. Although rich in metallic deposits, Nevada is not known as a producer of diamonds. Indeed, the general lack of deposits led mining men to conclude that there were no diamonds in Nevada. And then a man named E.L. Hews proved them wrong again. In 1905, Hews discovered a small diamond-bearing deposit a few miles southeast of Tonopah, near the Tonopah-Silver Bow road. A small diamond rush ensued and suddenly men began to recall an old story told of a lost diamond mine somewhere in the McCullough Mountains of southern Nevada.

It was 1872, the year of the great Diamond Hoax in Colorado. An unknown prospector wandering the McCullough Mountains stumbled upon a small patch of weathered, bluish-gray rock which seemed to be volcanic in origin. The prospector noticed a number of small lustrous crystals mixed in with the decomposed blue rock. He collected a few of them and continued on with his search for precious metals. A few years later, the prospector got the shock of his lifetime when he discovered that the crystals were actually diamonds. He had nearly forgotten all about them but he was sure he could find the diamond patch again. But when the prospector returned to the McCullough Mountains, he was unable to find the deposit of blue rock. It still remains hidden today.


The history of mining in southern Nevada extends back at least two centuries before the coming of the white man. Crescent Peak is a case in point. Located near the southern end of the McCullough Mountains, Crescent Peak was a source of turquoise for a number of Pre-Columbian Indian tribes. Their ancient workings were rediscovered by white prospectors during the 19th Century.

Spanish prospectors penetrated the southern part of Nevada sometime during the late 1770's. They were followed by Mexicans in the early 1800's and then by Americans shortly thereafter. American prospectors arrived in force during the 1850's. In 1856, a party of Mormons discovered outcrops of lead ore in the mountains near present-day Las Vegas. They later learned that the ore was rich in silver. In 1863, Mexican prospectors discovered a swarm of small gold-bearing veins near Crescent Peak. The Mexicans worked these deposits for many years, using crude arrastres to separate the gold.

The 1890's were dismal years in Nevada's mining history. Except for a small area in the south, the state was in a mining slump. The only bright spot was southern Nevada where two major strikes were made. The largest and most important discovery of the 1890's took place in the Delamar Mountains, 50 miles southwest of Pioche. The Delamar ore bodies would eventually produce

nearly $15 million worth of precious metal. The Delamar strike was followed up by the discovery of rich gold deposits in the hills of southern Clark County. The mining town of Searchlight quickly sprang up nearby. Searchlight turned out to be the largest and most important gold-mining district in Clark County. It produced nearly 250,000 ounces of the yellow metal.

During the 1900's, Nevada's mining industry was reborn. The state's second major boom began with the discovery of the Tonopah ore bodies in the spring of 1900. A succession of incredible strikes followed including Goldfield in 1902, Manhattan in 1906, and Round Mountain later that same year. In southern Nevada, several smaller strikes occurred in the years following the Tonopah discovery. In 1904, rich silver deposits were discovered on the slopes of Crescent Peak. A small silver boom brought scores of prospectors to the mountains of southern Clark County and a mining town called Crescent sprang up near the silver veins. The town quickly faded when the ores ran out.

In 1905, the richest deposit in the Sunset District was discovered by a solitary prospector. The mine became known as the Lucy Grey. In 1908, alunite deposits similar to those at Goldfield were found on the northeastern fringe of the McCullough Mountains. Unfortunately, they contained very little gold.