Face sampling is the cutting of pieces of ore and rock from exposed faces of ore and waste. The faces may be natural outcrops or
Before assaying, original samples must be cut down, often in several stages. Each cut involves, in effect, the sampling of a sample, the final portion
At the beginning of the use of the electric furnace, for the manufacture of calcium carbide and ferro-alloys, experimental work was conducted in it upon
In the preceding pages some unit costs of sinking, drifting, cross-cutting, and drilling have been presented, together with a few costs covering entire churn-drilling campaigns.
Drilling is employed extensively, either as the principal exploratory method or to supplement exploration by underground and surface workings. Three principal types of drills are
Prospecting for lode deposits begins with a search for mineralized outcrops, the key to the existence of which may often be found in mineralized float
Prospecting for placer gold, except perhaps in the case of buried placers, is the simplest form of prospecting. Gold, platinum, and tin are the principal
A brief summary of the methods employed and the costs of prospecting and exploration has been presented in the preceding pages. The primary object of
This report summarizes mining practices of a large number of metal mines in the United States and foreign countries. The adaptation of mining methods best suited
Of the treatment of the slime-pulp of gold- and silver-ores by cyanidation, agitation is an essential part. When prepared for treatment, this pulp, consisting of