Vanning Buddle Concentrator

I tested an ore, which was peculiarly difficult to treat, on several concentrators then in general use, including the Frue-vanner, the Luhrig table and the Cornish buddle. Owing to the character of the ore it had to be crushed- to a very fine state of division, and the results obtained were far from satisfactory; a … Read more

Refining Zinc Precipitates: Cyanide Leaching of Gold & Silver Extraction

Attempts to discover, for the cyanide process, a better precipitant than zinc have been unsuccessful. Hydrogen sulphide, sulphurous acid, ferrous sulphate, etc., precipitate gold and silver from cyanide solutions either not all or incompletely. Aluminum has been tried, but it costs too much, and cannot be used in solutions containing lime. Charcoal has been used … Read more

Copper Refining: Explained Step-by-Step

In refining copper, the metal is melted down in a reverberatory furnace in a more or less oxidizing atmosphere and then further subjected to an oxidizing smelting in order to eliminate the common impurities, most of which have a stronger affinity for oxygen than has copper. In these operations some of the copper is oxidized … Read more

Ore Sampling

This paper is intended partly as a summary of the conclusions that have been arrived at by various authorities on this matter, and also with a view to initiate some discussion on the subject, especially as most of the quartz gold mines in Victoria are operated without having any proper assay plans or any idea … Read more

DIY Portable Fire Assay Furnace

In the early stages of opening up a mine, when there is some uncertainty as to its future career, necessitating caution in laying out works of a permanent character, the want is often felt of an assay furnace, easily built and easy, of transportation, should the “ mine ’’ prove to be “ no mine.” … Read more

Free Milling Gold Laboratory Testing

Friends often ask how accurate the work of our little stamp-mill is, or express the opinion that a little mill cannot do good work. As a reply we would like to place on record the results of a few tests. There are two periods of work in our laboratory; the fall term, when the class … Read more

Lead Refining by Electrolysis

A solution of lead-fluosilicate, containing an excess of fluosilicic acid, has been found to work very satisfactorily as an electrolyte for refining lead. It conducts the current well, is easily handled and stored, non-volatile and stable under electrolysis, may be made to contain a considerable amount of dissolved lead, and is easily prepared from inexpensive … Read more

Electric Rock Drill

Electric power in mining-operations is now successfully applied to haulage, hoisting, lighting and pumping; and until lately, drilling was the one department of mining in which an electric source of energy had not been introduced. Drilling by electric power has been the field for much investigation and several forms of electric-drills have been tried; but … Read more

Silver Lead Ore Processing by Roll Crushing & Jigging

The following brief paper is intended, to apply to the concentration of the silver-lead ores at Broken Hill, New South Wales, generally, but more particularly to the process as applied to the ores in the Block 10 mine. The attached plans are similar in many respects to those prepared recently for the Block 10 Company. … Read more

Centrifugal Elevator: Gold Dredge Tailings Transportation

The centrifugal elevator invented and patented by the writer is designed for the purpose of conveying the tailings of a gold dredge to such a distance that they shall not impede the dredging operations. Formerly this was usually accomplished by means of a belt of buckets travelling round a ladder set at an angle of … Read more