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Mining interests in this country have long attracted considerable attention, and, at the present day, instead of showing any signs of abating, the interest manifested is greater than ever before.
Men of every age, character and social condition hurry to the mining districts in search of fortunes, sanguine of success, but wholly unprovided with the means of attaining it; without any knowledge of mining enterprise; without any guide or assistance from the experience of others-trusting only in their own judgment, which is in these matters entirely uneducated and practically worthless, or in luck, as much a superstitious fancy in this business as in any other.
Any business, to be successful, requires special knowledge and skill, and this is peculiarly true of mining, since it is based upon a correct understanding of several of the most difficult of the sci
Fortunes have been wasted in the senseless search for mineral veins in places where they could not by any possibility exist, and many valuable mines have brought nothing to their discoverers because they did not know how to make good use of their property after they had found it.
A thorough knowledge of geology, mineralogy, metallurgy and chemistry would require a long course of study; but as very much of these is not important to the prospector or miner, it is proposed in this small volume to bring together in a convenient shape so much of them as is directly valuable to him, that he may have an opportunity of learning to recognize the metalliferous rocks, the precious ores and their simple tests and assays, as well as their (vi)
differences from deceptive and worthless minerals, and the proper methods of proceeding in prospecting for mineral veins or deposits.
Without such knowledge it is as impossible to succeed, as for a lawyer who has no knowledge of law, or the physician who is ignorant of medicine. Many ignorant men who enter the mining districts pretend to despise science-forgetting that science is the recorded experience of those who have worked most earnestly and most successfully. It is a very common experience that these selfsufficient men, after wasting their time in the search for ore in impossible places, and exhausting all their money in utterly useless undertakings, return home on foot sad and dejected, bitterly denouncing the country and the mines, while they alone are to blame. If this volume shall prove to be of assistance to the prospector and investor, it will have accomplished the purpose of the author. Should the reader desire to push his study further in this direction, he will find the following books to be authoritative:
In this book great pains have been taken to avoid the use of scientific terms as far as was possible, as it was thought best to present the subject in the form most useful for practical use.
No attempt has been made to teach accurate assaying for the simple reason that no man can well be both an assayer and a prospector, and this book is written for the latter.
Since, however, it often happens that a prospector, or any individual, desires to learn whether an ore carries any metal, and
whether there is much or little probably present, a number of blowpipe, chemical and special tests have been described, which will be found useful. In case the reader desires to learn assaying, he should make up his mind to devote his time and attention to it alone, provide himself with good books and good apparatus, and remember that accuracy and success will result only from patient and careful application.
Under this head it is proposed to present a brief, classified description of the minerals found most abundantly in the rocks, also of the most important metallic ores and other minerals ordinarily met with in prospecting and mining.
In the examinations of a mineral it is specially necessary to notice accurately its lustre, color, streak, hardness, tenacity, crystal form, cleavage, specific gravity, and any other peculiarites which will enable us to recognize it another time, or to distinguish it from similar minerals.
The chemical composition of a mineral is important, but as the prospector will at first probably have no means of determining this for himself, he will learn to recognize the minerals by their other properties, and to find its constituent elements by reference to the book.
The LUSTRE of a mineral may conveniently be described as being metallic, like the polished surface of a metal, vitreous or glassy, waxy, resinous, or dull.
COLOR is exceedingly various even in the same mineral, but nearly all minerals have some one or few prevalent colors, these will be given.
STREAK is the mark made by rubbing or scratching the mineral over a hard white substance, such as unglazed china or stoneware, the rough edge of a broken plate, a piece of white rock, or any substance of light color which is harder than the mineral to be tested. In case no such substance is handy, powder a little of the mineral with a hammer, and rub it with a knife blade on a white piece of paper. The streak shows the color of the powdered mineral which is often characteristic and very different from the color of the mineral. Thus iron pyrites has a brass-yellow color and a black streak, while copper pyrites scarcely to be distinguished from it in appearance has a greenish streak.
HARDNESS is the ability of a mineral to scratch other substances, and is determined by this means. The hardest substance known is the diamond, and it is therefore called ten or the highest in the scale. It will be easy to collect from the rocks a scale of hardness sufficient for all practical use.
Thus Tale may be taken as the first of the scale, and its hardness is called 1. The others easily secured are
Gypsum 2. Calcite 3. Fluor Spar 4. Feldspar 6. Quartz 7. Topaz 8. Corundum 9. Diamond 10.
Substances harder than quartz are not commonly met with. If any of the foregoing substances are not easily obtained others of similar degree of hardness may be substituted for them-thus roll sulphur (brim