Underground Mining Methods of Zinc Ore

The varying physical character and large extent of the Broken Hill lode necessarily involve the employment of a variety of underground methods. The lode had its origin in an extensive fault plane traversing metamorphosed schists conformably, as a rule, with their beds of stratification. The underground waters carrying minerals in solution deposited their contents in … Read more

Underground Mining Methods of Copper

The system of stoping as practiced was eminently satisfactory to supplement the steam-shovel operations without injuring the ore reserves of the property through a mixing of capping with ore. It had the advantage that all ore produced was absolutely free from waste, since both stopes and development drifts were discontinued when capping was reached. The … Read more

Evaluate Metal Segregation in Gold Bullion

Several years ago the writer was connected with the Mint and Assay Service of the Federal Government as Assistant Assayer at the Salt Lake Assay Office. At that time cyanide bars formed approximately half of the bullion purchased by that office. Disagreement in valuation between the producer and the office was not infrequent and to … Read more

Copper Electrolytic Refining Process Explained

Experiments on a Porphyry Copper Ore: This research was done partly in the non-ferrous laboratory of the Department of Metallurgy of Columbia University, under the direction of Dr. Edward F. Kern, and completed elsewhere. Acknowledgment is due to Prof. Arthur L. Walker, Dr. Edward F. Kern and Dr. William Campbell of the Department of Metallurgy, for their … Read more

Platinum Alloys with Tungsten & Molybdenum

Metallurgical research has discovered many an alloy possessing properties not combined in any single metal, and progress still consists chiefly in the investigation and utilization of alloys. In the case of iron, the demands of automobiles, high-speed machines and high-duty engines have led to the production of special iron alloys which will meet any reasonable … Read more

Natural Flotation Reagents form Plants

The reagents now used in flotation consist of various acids or salts, which may be either electrolytes or nonelectrolytes, dissolved in water and some substance or combination of substances, which function as collecting or frothing agents. At times the only dissolved salts present are those naturally occurring in the water used. The general effect of … Read more

Drill Holes Assay Result Interpretation

In the exploration of a copper deposit by drilling, obvious advantages are to be gained from a distinction between primary and secondary ore. Perhaps the chief of these is the aid which such a distinction renders in determining where a given hole should stop. The copper assay, often a sufficient guide, cannot always be exclusively … Read more

Lighting Underground Mine & Illumination

In preparing this paper the object has been to set forth facts relating to lighting or illumination problems faced in underground mines, which, judging from the results realized in the iron and steel and other industries somewhat similar to mining, will tend toward furthering safety, production, and contentment of employees, as well as economy of … Read more

Miner’ Safety Lamps

While electric lamps both of the cap and hand type are being introduced into many mines requiring the use of safety lamps, the oil-burning safety lamp is still used in the great majority of cases, and even where the former are used the latter must continue to be employed when testing for gas. It is … Read more