Two Montana Cities Part II Butte
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Quartz locations were made on and near the present site of Butte as early as 1864. In 1867 the town site was laid out, and Butte had a populations of nearly 500 souls. The early comers were only moderately successful in their ventures, however, and in time the placer claims were exhausted.
In 1875 came the startling discovery that the “black ledges of Butte” were rich with silver. The news spread rapidly. Old claims were relocated, and smelteries and mills erected. The camp grew readily. In a year the Utah and Northern road reached the place, and the present era of wealth and progress was fully inaugurated. This, in brief, is the history of Butte. All its trails and disappointments came at an early day, and when once overcome, never returned. Today the Utah and Northern furnishes its southern outlet, and the Montana, Union, and Northern Pacific its eastern and western. Before another year passes the Manitoba will give it still another direct connection with the outside world, and with other local lines will bring it into closer communication with Helena and the various districts of Montana.
The mines of Butte are of two classes-one silver, the other copper-bearing. The silver ores vary in richness from fifteen to eighty ounces of silver per tone. Most of the silver veins also contain from $4 to $12 per ton gold. Some of the copper mines carry silver, but the percentage is small. The principal copper ores are copper glance, erubescite,a nd pyrites. The rough ore assays from 8 to 60 per cent copper, and most of it bears a concentration from two to two and one-half tons into one, with a small loss in lastings.
The process of mining as practiced at Butte is of too complicated a nature to be properly described by a layman, and I therefore quote from an expert. “The silver ores,” he says, “are either free or base. In the first the silver contents are extracted after the ore has been stamped by simply mixing it with mercury in water, the precious metal amalgamating readily with the quicksilver. In base ores, however, the process is more expensive and complex. After the ore had been hoisted from the mine, it is conveyed in handcars to the upper part of the mill, where it is put through large iron crushers, which reduce it to about the size of walnuts. From the crushers it drops to the drying floor, where all the moisture it contains is evaporated, and where it is mixed with proportion of salt varying from 8 to 10 per cent. of its weight, the amount of salt depending on the baseness of the ore. When thoroughly dried it is shoveled under the stamps-large perpendicular iron bars weighing 900 pounds-which are raised by machinery and permitted to drop on the ore below at the rate of about fifty strokes per minute. The effect, of course, is to crush the ore to powder, in which condition it is taken automatically to the roasters. These are huge hollow cylinders, revolving slowly, and filled with flames of intense heat, conveyed from the furnaces below by means of a draught. As the cylinders revolve, the actions of the heat drives off the sulphur in the ore, liberated the chlorine in the salt, and a chemical change takes place in he nature of the silver in the ore, making a chloride of what was formerly a sulphide of silver, and rendering it susceptible of amalgamation with quick silver, just like the silver in the ‘free’ ore mentioned. From thh roasters the pulp is then conveyed by tramway to the pans-large tubes filled with water, in which quicksilver is placed with the pulp. The mass is then violently agitated, so that every particle of the sliver chloride comes in contact without eh quicksilver, by which it is taken up. The whole is then conveyed to the settlers-another series of tubs in which the water settles, and from which the metal is drawn in eh form of amalgam. This is afterward subjected to heat, volatilizing the quicksilver, which is afterward condensed for use again by means of cold-water pipes, leaving the silver in a pure metallic state, to be melted into bars and shipped for coinage.”