902

Metallic Copper: Quick Silver & Gold Assay Method

Under the above title it is desired to bring to the attention of assayers a short-cut method which has been perfected by Mr. A. S. Warren, of Buffalo, and the writer; has been used several years at three “ Lake copper ” refineries in occasional alternation with the regular “ combination,” or “ wet and … Read more

Mine Timbering

So many emergencies that crop up in mining necessitate a departure from ordinary methods that the writer has been led to illustrate a few of the examples that have come under his notice during a somewhat lengthy career; and as most of the methods illustrated are certainly outside the ordinary, it may be hoped that … Read more

Klein Jig & Classifier

Concentrating-Machinery has been wonderfully improved during the past few years both in technical efficiency and in economy of power; and, in the writer’s opinion, the prosperity which the mining industry has of late enjoyed is due in large part to this improvement. Many properties are yielding handsome profits at the present time which were considered, … Read more

What Factors Control the Depth of Ore Deposits

When asked to lecture at Bendigo on the geological factors that determine the depths of ore deposits, I hesitated for a little before agreeing to lecture on the theory of deep ores in the city world-famous as the pioneer of deep gold mining. If there be one place, wherein the conditions of deep-seated ore deposits … Read more

How to Measure & Detect Gold & Silver in Trace Amounts

For a number of years I have, at odd times, tried to perfect a method of assay sufficiently delicate to find and estimate very small/trace quantities of gold and silver. The object in view was to examine rocks remote from veins or mineral areas, in order to test the probability of the lateral-secretion theory. Having succeeded … Read more

Building a Reverberatory Furnace in Adobe, Stone & Wood

The building of reverberatory furnaces (Fortschaufelungsofen) where ordinary brick, fire-brick and iron are comparatively cheap, is quite a different matter from the building of such furnaces in isolated camps, where proper material is only to be obtained at high cost and with long delays. Time is always a large factor in metallurgical operations, and the … Read more

Gold Mercury Amalgamation Methods

I was manager of a mining enterprise where the ores were composed principally of iron pyrites (much decomposed), in a quartz matrix, with native gold in very irregular grains. Some portions, however, carried their metallic value in a matrix of calcite and siderite. The mill in which the ores were treated consisted of two 800-lb. stamps, … Read more

Antimony and Tellurium Alloys

The study of an entirely new series of alloys may be undertaken from a desire to obtain knowledge applicable to the perfection of industrial alloys, or merely to test certain theoretical considerations. In the case of antimony & tellurium alloys, the theoretical side only is at present important; but it is hoped that the results … Read more