Part 1 Early Mineral Exploration

Mining in the Stillwater complex began not with the platinum group metals, but with chromite and copper nickel. Since the late 1800s, the Stillwater complex and adjacent rocks were known to contain copper, nickel and chromium.

Copper-nickel exploration

Sulfide rich rocks were discovered within the Basal series, the metasedimentary rocks immediately below the complex, in 1883. Jack Nye and brothers Jimmy and Jonas Hedges found the sulfide rich rocks in Mountain View, Benbow and Initial Creek areas. Nye traveled to Minneapolis and submitted his findings. On the basis of those findings, the Stillwater Mining Company was incorporated in the summer of 1884 and a mining project commenced in 1885.

On September 10, 1885, Nye sold to the Stillwater Mining Company his quartz claims in the Benbow and Initial Creek areas and a placer claim in the Stillwater River Valley. On October 2, 1885, he sold quartz claims in the Verdigris Creek area and additional placer claims to Stillwater. Two weeks later, Stillwater sold these claims to the Minneapolis Mining and Smelting Company. After the transaction, construction of Nye City began.

Nye City was located just west of the American Chrome Company hospital building. By 1887, a small smelter had been assembled and the town grew to a peak population of 300 to 400 people, and counted, at one time, six saloons, a store, a commissary, a boarding house, and an assay office.

A fly in the ointment of success brought things to an abrupt end. A government survey of the Stillwater basin revealed that Nye City was not part of the Federal domain included in Gallatin County, but was actually on Crow Indian Reservation lands. Because government laws prohibited such exploitation of tribal lands, the mining operation had to be dismantled and removed. The last official record of Nye City was a March 28, 1889 judgment deed for $12,255. In 1890, the Crow Indians ceded the land, which reopened the Stillwater basin to mining and claim staking.

In 1904, a group of prospectors banded together for a trial shipment of ore. A six-ton shipment representing 500- to 1,000-lb units from individual claims was sent to Omaha, Nebraska, for smelting. Unfortunately, recovery was substantially less than the assays indicated, and the value of the ore did not warrant production. Interest in the patented claims vanished.

Little more was done on the claims until Bill Mouat, a nephew of the president of the Minneapolis Mining and Smelting Company, became interested sometime around World War I. He hired Otto W. Miller, a Columbus, Montana, resident with some mining experience, to redeem the claims. This started a new episode of development.

The Mouat property was brought to the attention of the Anaconda Minerals Company in the early 1920s. In a 1925 report by Vincent D. Perry, later president of the Anaconda Minerals Company, preliminary sampling results included the first geologic maps of the property. On the basis of the assay results, further work was recommended. In 1937, 11 holes were drilled totaling 6,432 feet and adits in the Verdigris Creek area were assayed. The results showed lower grades than indicated by Perry’s sampling and determined that the massive ore stores had only limited continuity. In 1940 and 1941, the U.S. Bureau of Mines conducted exploration with 5,981 feet of drilling in eight holes, then sampling and metallurgic testing of the results. This provided data for the considerable mapping work was conducted throughout the 1940s, which was eventually published in 1954 as a geologic outcrop map of the Mountain View area. This plane-tabled map, at a scale of 1:1,200, covered the Verdigris Creek-Mouet nickel mine area and served as the fundamental source of information for this area for many years.

In 1966, the Anaconda Minerals Company began new evaluation reconnaissance of the low-grade, high-tonnage, copper-nickel resource in the lower margin of the Stillwater complex. Full scale project work began in 1967, including drilling in September.

The project focused on areas of known mineralization, i.e., Initial Creek, Mountain View, Nye Basin, and Benbow. Geochemical analysis for copper and nickel and a number of other techniques were used to define anomalies and drilling targets. Anomalies were most favorable in Mountain View, Nye Basin and Benbow areas. From 1967 to 1970, a total of 92, 041 feet of core from 95 holes were drilled in the Mouet Ni-Cu prospect in the Mountain View area, 9,626 feet from 15 holes in the Nye Basin and 5,564 feet from 9 holes in the Benbow area. Two adits were collared and driven during this period: the Mouet tunnel was begun in September 1970, and advanced 1,547 feet before work was stopped in July 1971; the Nye Basin adit was begun in October 1970, but only advanced 206 feet before stopping in January 1971.

Geochemical and geophysical surveys also suggested that significant anomalies existed in the Cathedral Creek-Bluebird Ridge area west of Initial Creek, in the Crescent Creek area and in the Gish Mine area. By 1970, four drill holes with a combined footage of 1,693 feet had been drilled in the Crescent Creek area.

Although this work indicated a moderate to large reserve containing 0.25 weight percent Cu and 0.25 weight percent Ni in the east third of complex, a combination of findings and events brought the project to a near standstill: Metallurgic problems with the ore were found; environmental concern over the area increased; in Chile, the newly elected Allende government expropriated Anaconda’s holdings there. As a result, work on the Stillwater complex was withdrawn to assessment work and very limited drilling.

Finally, in 1977, Anaconda initiated a re-evaluation of their properties. Geological mapping, compilation, evaluation and metallurgic testing were resumed. Additional holes were drilled and geophysical surveys were used to delineate and define anomalies. A helicopter-borne precision proton-magnetometer survey was completed over the entire Stillwater Complex in June, 1978.

Other companies were exploring the area for copper-nickel in the 1960s and 1970s as well. Under the authority of the Freeport Exploration Company, in 1965, a search for mineralizations of copper-nickel sulphide of economic concentrations, This geophysical survey delineated seven conductive zones, three of which coincided with known copper-nickel occurrences within the Basal series and a fourth with a major fault structure and post mineral diabase dike. Three geophysical anomalies were singled out for further study because they showed a potential association with as-yet-unrecognized copper-nickel mineralization. After further investigation, all three were secured with with unpatented lode claims in 1966.

After that discovery, prospectors further explored the lower part of the complex, among them William M. “Bill” Mouat and scientists from the Anaconda Minerals Company, Amax Exploration, Amoco Minerals Company, Cyprus Mines Corporation, Lindgren Exploration Company, Princeton University, University of California at Berkeley, the U.S. Geological Survey and the U.S. Bureau of Mines. Little of this early activity was recorded, but by the 1930s, sulfide occurrences at Benbow, Mountain View, Crescent Creek, Placer Basin and the Boulder River were well known.

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