March/April 2009

Economic Geology

Butte, Montana (Part 1)

By R. J. Cathro

The miners of Idaho were like quicksilver. A mass of them dropped in any locality, broke up into individual globules, and ran off after any atom of gold in their vicinity. They stayed nowhere longer than the gold attracted them” (Bancroft, 1890). Although Bancroft was describing the Boise camp in Idaho, 400 km southwest of Butte, in 1862, it applied equally well to every gold rush between California and Alaska.

At each new point of promising discovery, camps of tents and ‘wikiups’ (brush shelters) were quickly replaced by towns of log cabins, frame buildings, and the few brick structures of which each community boasted so inordinately. At first logs and whip-sawed lumber served all purposes, for rockers, sluices, and houses, but soon sawmills were brought in and were run literally all day and night. Men waited in line to buy the green lumber as fast as it was cut.

~Paul, 1963

Although the colourful history of Butte has resulted in an extensive bibliography, this chapter is restricted to the people and events that led to the discovery and investigation of the copper deposits, and what Butte taught geologists about the origin of metals and ore deposit models.

The copper market was quite small until the 1870s, which marked the transition between the period when it was used primarily for roofing, alloys, and pots and pans, and the emerging age of electricity. The potential of electricity for general usage, including Alexander Graham Bell’s telephone, was demonstrated at the Centennial Exposition in Philadelphia in 1876. The first electrical generating plant for street lighting was built in New York in 1882, coincident with the invention of hard-drawn copper wire and installation of interior electric lights in Wanamakers’s store in Philadelphia. By 1880, Thomas Edison and others had received patents for incandescent lighting and began to experiment with the trolley car. The invention of transformers and the development of electrical transmission also created an enormous demand for copper wire.

Beginning in 1844, copper mines on the Keewenaw Peninsula of Michigan, on the shore of Lake Superior, produced most of the modest U.S. copper requirements. Even after the discovery of the huge Calumet & Hecla ore body in 1864, this copper district was unable to satisfy the growing market and the price of copper steadily increased from 50 to 75 cents per pound by 1875. Impressive as the Michigan copper district was, its geology was relatively simple and it didn’t make a major contribution to the study of economic geology.

Rapid industrialization in the 1880s and 1890s required a reliable supply of low-cost copper that was far beyond what could be supplied by mines in Europe and elsewhere. Much of that supply was destined to come from the ‘The Richest Hill on Earth’ at Butte, Montana, which was situated at the northwestern frontier, far from the nearest railhead or seaport. In addition to its national and international economic contribution, Butte was also a unique and complex mineral deposit that would expand the boundaries of the science as geologists studied its origin. At the same time, it would demonstrate to the world how a mining camp and a frontier society should not be governed. In spite of technical and human obstacles, Butte would eventually live up to its bold slogan and become the foundation of one of the first international mining companies, The Anaconda Company.

Anaconda is generally considered to be the first mining company that created an effective mining geology department. As we will see later, that did not happen just because mine managers developed an interest in the origin and geochemistry of ore fluids. It was partly a response to the very costly legal challenges that were spawned by the Apex Law, which were argued in court by well-paid experts who were familiar (or not) with the geology of the ore bodies. The complex vein systems at Butte were not what the German mining engineers had in mind when they developed the Apex rules back in the 16th century.

In common with many mining camps, the discovery of the Butte copper deposits began with the discovery of gold. As the army of newly trained prospectors dispersed from the California and Comstock rushes, several placer discoveries were made in Montana: at Bannack, about 50 kilometres south of Butte, in 1862; Virginia City in 1863; and Butte and Helena in 1864. More prospectors flocked in from the gold camps of Coeur d’Alene and Boise, Idaho, to the west, came up the Missouri River Valley from the east, or made their way northward from California and Nevada. Among the early arrivals were men from Cornwall, Ireland, and England and a good many Canadians. The Butte district was difficult to reach because it was situated in an isolated mountainous region between the western flanks of the Rocky Mountains and the Continental Divide.

The Bannack discovery, made on Grasshopper Creek by a party led by John White, soon resulted in a settlement of 500 people. Lode mining commenced the same year when two miners named Allen and Arnold began to treat quartz ore with a six-stamp mill built with iron salvaged from old wagons. A steam-powered, 12-stamp mill was brought from St. Louis in 1864.

The Butte discovery occurred on Silver Bow Creek, in the valley below the copper deposits, and sparked the usual stampede. Following experience gained in California and at Comstock, prospectors worked their way upstream to the future site of the city and the copper mines but only about 75,000 ounces of gold were recovered by 1867.

Some prospectors noticed that native silver was mixed with the gold and Butte soon entered a new phase of lode silver mining. The silver-rich area, situated at an elevation of about 1,500 metres, was variously described as “a long yellowish granite hogback… a wind-swept ridge” (Joralemon, 1934), and as “a conical peak… bare of vegetation, for chemical reasons”… with a “network of big veins,” some of which “contained rich silver ore right at the surface… and a little copper carbonate” (Rickard (1932). Today, exploration geologists would describe this as a ‘kill zone’ or ‘vegetation anomaly’ caused by the oxidation of sulphide minerals.

The first lode claims on what became the Anaconda copper mine were staked in 1864 and explored with a 25-metre shaft that intersected a two metre-thick vein of copper ore, but the results were considered disappointing because the gold values were low. Joseph Ramsdell and Dennis Leary discovered the first body of commercial copper ore on the nearby Parrot claims in 1866 and made a shipment to Swansea, Wales. Because it proved uneconomic to ship the raw ore so far, an unsuccessful attempt was made to treat it in a crude smelter on the site.

Butte enjoyed another brief silver boom after W.L. Farlin discovered some rich silver ore on the Travona claim. Although it was not amenable to treatment with an arrastra or crude smelter, five mills with 290 stamps were in operation by 1887 treating about 400 tonnes per day. Although silver and copper remained unattractive targets because Butte was over 650 kilometres from the nearest railway in Utah, the  exploration of the copper potential by men of vision continued.

To quote Rickard, “Butte produced three chromatic characters, Clark, Daly, and Heinze.” Clarke and Daly, who can be considered the fathers of Butte, couldn't have been more different. Their mutual dislike threatened to disrupt the economic and political life of the state, and historians agree that their feud debauched the political life of Montana from 1890 to 1900. Heinze will not be discussed until later because his role did not begin until copper production had been established for over a decade.

William Andrews Clark (1839-1925) was the more successful and influential of the two because he was more ruthless than Daly and outlived him by a quarter century. He was born in 1839 to Irish immigrants in Pennsylvania, moved with his family to Iowa, attended private academies, worked for a time as a schoolmaster, and studied law at Iowa Weslayan College. After gaining his first mining experience at Gilpin County, Colorado, he began to display entrepreneurial talent soon after gold was discovered at Bannack.  After opening stores and banks at Virginia City, Helena and Butte, he was well on his way to becoming a wealthy businessman when he made a major career change. Deciding that the future lay in mining and that he needed to know much more about it, he attended the Columbia University School of Mines in New York for a year before returning to Butte to build the Old Dexter silver mill and organize the Colorado & Montana Smelting Co.

Unlike most Western mining barons, Clark was fastidious, always neatly dressed and refined. He appeared to be mild-mannered, reserved and ingratiating, and prided himself on his sophistication, his appreciation of fine wines and his excellent art collection. Physically diminutive in size, he was also vain and liked flattery. Although he was acknowledged to be an astute businessman, he was generally considered to be vindictive, jealous, arrogant, obsessive, uncompromising and ruthless, with a reputation for treachery and selfishness — a man who considered any means justified to achieve success in business or politics.

Marcus Daly (1841-1900) shared only two characteristics with Clark: his Irish heritage and his vision and belief in the potential of Butte. Born of poor and illiterate parents in Ireland, he immigrated to New York at the age of 15, worked on the docks until he could arrange passage to Panama, and then made his way to California. He proceeded to learn mining the hard way in the Grass Valley gold mines and the Comstock silver mines, where he stood out for his natural talent as a foreman and his ability to follow and find ore. Daly was described as short and ruddy, affable and gregarious, profane, generous, modest and courageous — a born leader with simple habits and a large circle of friends, a man who inspired loyalty.

Daly first met George Hearst either at the Comstock camp or at Mineral Hill, Nevada, a mine that was controlled by Hearst and his partners in the Hearst Syndicate, James Haggin and Lloyd Tevis (see CIM Magazine, Vol. 3, No. 5, August 2008, p. 71). From there, he moved to Utah to manage a mine for the Walker Brothers, based in Salt Lake City, until he was sent to Butte in 1876 to find them a silver project. Daly had earned a reputation as a shrewd judge of mineral potential at a time when practical miners with a nose for ore like Hearst and Daly were held in higher esteem than graduates of the new mining schools in the United States or Europe. Daly proceeded to acquire the Alice mine, a small silver producer, and managed it for the Walkers in return for a small interest.

After examining the neighbouring prospect, Daly became convinced that Butte held great copper potential so he sold his interest in the Alice for $30,000 in 1881 and used it to acquire the Anaconda claim from the owners, Charles Larabie and Michael Hickey. A Civil War veteran, Hickey had staked it and named it after a Horace Greeley editorial in the New York Tribune that described how the Union army would encircle the Confederate forces ‘like a giant anaconda.’ He had staked his claim on a wide frost-shattered structure in 1875 or 1876 after earlier miners looking for gold and silver had abandoned their claims.

The year of the purchase, 1881, was an important milestone for Butte because it marked the arrival of the Union Pacific Railway from Omaha, Nebraska. After 1884, another shorter connection became available to the Pacific Coast via the Northern Pacific Railway. Daly invited the Walkers to participate when he realized that he couldn’t afford to sink a shaft and develop the Anaconda by himself. When they declined, he turned to the Hearst Syndicate, which was fresh from its success at the Homestake mine in South Dakota. Hearst had held Daly in very high regard ever since he had acted on a Daly tip and purchased the Ontario gold and silver mine in Utah for $30,000 on behalf the syndicate. Between 1872 and 1883, the Ontario mine had yielded a profit of $17 million.
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