172 CONTRIBUTIONS TO ECONOMIC GEOLOGY, 1902. [bull.21i1 
few inches wide. Mr. George Hearst, visiting the district about 1S82, 
selected the site of the present Anaconda shaft as the most suitable 
place for future development. At a depth of 300 feet a crosscut run 
from the shaft encountered 5 feet of copper glance, and the ore was 
extracted and shipped to Swansea. During these early years the cop- 
per ores showing on the surface of several of the claims were receiving 
attention, and in 1867 an effort was made to smelt some of the ore from 
the Uarrot lode. 
To Senator W. A. Clark is due the first successful development of 
the copper veins of the district. In 1872 and the succeeding two years 
he began development work on the original Colusa, Mining Chief, an 
Gambetta claims. The ore extracted was shipped 400 miles in wagon 
to Corrine, Utah, thence by rail to the East, some of it going to 
Swansea, Wales. 
One of the purchasers was the Boston and Colorado Smelting Com- 
pany, located at Black Hawk, Colo., and in 1879, at Mr. Clark's sug- 
gestion, this company formed the Colorado and Montana Smelting 
Company and erected reduction works on the present site of the 
Colorado Smelter, thus furnishing a local market for the copper as 
well as the silver ore of the district. This smelter gave a great 
impetus to copper mining in the district, as previously shipments con- 
taining 35 per cent of copper from the Green Mountain claim gave no 
profit to the shipper after the cost was paid, although the gross value 
of the ore was $130 per ton in copper, the average price of that ore 
being 18f cents per pound. In silver the ore carried not less than $50 
per ton, but the works charged a high price for treatment, owing to ' 
the presence of arsenic, which made the metal brittle. 
Soon after the erection of the Colorado Smelter the Parrot, Montana 
Copper, Clark's Colusa, and the Bell Company began smelting opera- 
tions. The matte produced by these works was shipped to Eastern 
markets for refining. In 1884 the Anaconda Smelter began operal 
tions, followed rapidtyby the formation of the Butte Reduction Works, 
Boston and Montana, Butte and Boston, and Montana Ore Purchasing 
companies. The completion of the Utah Northern Railway from 
Ogden to Butte in December, 1881, and the connection of this railroad 
with the Northern Pacific at Garrison in 1893, and the coming of the 
Montana Central, part of the Great Northern system, in 1888, and of 
the local branch of the Northern Pacific in 1889 — all added to the 
prosperity of the camp. 
In the history of Butte the metallurgical advance in the treatment 
of the ores has been very steady; the free-milling silver plants gave 
place to chlorination and roasting, and these in turn to other improve- 
ments, so that the ores which could be profitabl} 7 treated became lower 
and lower in grade. With the great decline in silver of 1892-93 the 
silver-mining industry of the district became less and less important, 
until in 1890 all the large plants were closed down, and since that time 
