Geology and Mines of the Upper Blackfoot Valley, Montana

The purchase and continued operation of the Mike Horse mine in the Heddleston district, by the American Smelting and Re­fining Company, gives the Blackfoot Valley a renewed promise of a prosperous future in its role as a mining district. In the past, large amounts of placer gold were recovered from the gulches of the area, however, because of the transporta­tion facilities, only the upper portions of a few lodes were exploited by the early miners.

Oxygen Enriched Atmosphere Roasting

The possible benefits of oxygen enriched atmosphere roasting have been known to metallurgists for many years, but only since the development of equipment and processes to produce cheap oxygen in very large amounts has much ser­ious consideration been given this matter.