The Inhibitory Effects of Carbonaceous Materials on the Cyaniding of Gold Ores.

Carbon and carbonaceous material have been known to have a deleterious effect upon the cyanidation of gold and silver ores since the very beginning of the process. Organic matter is a common source of impu­rities in cyanide solution, its reducing effect being notorious.

A Study of a Carbonaceous Gold Ore

The presence of graphite in the ore of the Missouri-McKee Mine has made its treatment by the methods now used quite unsatisfactory. The study was undertaken to de­velop a new flow sheet which would give a high recovery and yet be economical enough to handle low grade material.

Conodonts from the Quadrant Shales of Montana

Conodonts have not been known to exist in Montana prior to the discovery of the specimens discussed and described in this paper. With this fact in mind, the author has endeavored to correlate the species of seven genera found in the Quadrant formation of Montana with similar micro-organisms from other North American areas.