Bituminous Coal
Occurrence of Carbon combined with Hydrogen: Blende and galena have been deposited in coal in the outlying basins of the Coal Measures, scattered along the broad, northern marginal belt of the Ozark Uplift. Near the reservoir at Sedalia, Mo., a basin in the Second Magnesian Limestone carries a little coal of fair quality, in which dark […]
Bituminous Shales
Rich deposits of blende, formed in great part by the secondary enrichment of smaller, or less mineralized, primary ore- bodies, are found near the surface in the Joplin, Mo., district, in the vicinity of Carthage, Lehigh, Central City and Reding’s Mill. At these localities the ore occurs in two ways: in the beds of soft, […]
Organic Matters of Limestones
In mining-regions where the ores occur in limestone, it is observed that in most instances the largest and most productive mines are in belts or zones of crystalline limestones which are either exceptionally pure lime-carbonates or, more frequently, dolomites with only a small amount of insoluble matter. Such formations, peculiarly favorable for ore, are rocks […]
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 […]
Prospector Survival Equipment List
The engineer has often to penetrate difficult or unknown regions. Mineral, irrigation, boundary and railway problems frequently necessitate journeys through, or long residence in, localities whence sustenance cannot be drawn. The selection and conveyance of provisions, outfit and implements thus become a matter of the first importance. Scientific skill, even of the highest order, is […]
Method for Calculating Volume of Small Mine Drifts
In the Engineering and Mining Journal there appeared an article by Fred T. Greene, describing a method of measuring stopes by the use of strings, a clinometer and a tape. I had occasion to use a somewhat similar method, for the purpose of accurately ascertaining the volume of a very irregular drift connecting two mines. This […]
Alluvial Mining Methods
As it is my opinion that deep alluvial mining methods in Victoria and in the Murray Flats in New South Wales are practically in their infancy, and considering that we, the old school, of alluvial miners, who have thirty or forty years’ experience to guide us, must in the natural order of things hand over the management […]
How to Measure the Density SG of Rock: A DIY Prospector Tool Rule
The determination of specific gravity dates from such antiquity, and the various published methods of determining it are so numerous, that one may well be skeptical as to the value of a new means of obtaining so well-known a quantity. I make no claim to any great novelty for the little device here described, the […]
Gold in Granite & Plutonic Rocks
A recent paper by Prof. George P. Merrill, Curator of the Department of Geology of the U. S. National Museum, Washington, upon ” An Occurrence of Free Gold in Granite,” describes an interesting instance of the dissemination of this noble metal in the substance of granite of normal composition believed to be from Sonora, Mexico. […]
Plans How to Make a Hanging Compass
In working brown iron-ore mines on the system employed at Longdale, namely, stoping from the top down, the usual procedure is to drive a succession of upraises from the lowest adit to the highest, or to the top of the deposit, as the case may be. These upraises are usually driven 120 feet apart, along […]