Chapter XXI: The Training, Opportunities, and Ethics of the Economic Geologist

Economic geology is now an established and well-recognized profession, but there is yet nothing approaching a standardized course of study leading to a degree in economic geology. There are as many different kinds of training as there are institutions in which geology is taught. Within an institution, also, it is seldom that any two persons take exactly the same groups of geologic studies. This situation allows wide latitude of training to meet ever changing requirements, but in other respects it is not so desirable.

PURE VERSUS APPLIED SCIENCE

In no institution are all the applied branches of geology taught. There is constant pressure for the introduction of more applied courses; this seems to be the tendency of the times. The economic geologist, fresh from vivid experiences in his special field, is often insistent that a new course be introduced to cover his particular specialty. Any attempt, however, to put into a college course a considerable fraction of the applied phases of geology would mean the crowding out of more essential basic studies. To yield wholly to such pressure would in fact soon develop an impossible situation; for, on the basis of time alone, it would be quite impossible to give courses on all of the applied subjects in a training period of reasonable length.

On the other hand, the failure to introduce a fair proportion of applied geology, on the ground that the function of the college is to teach pure science and that in some way economic applications are non-scientific, seems to the writer an equally objectionable procedure,--because it does not take into account the unavoidable human relations of the science, which vivify and give point and direction to scientific work. The development of science in economic directions does not necessarily mean incursion into less scientific or non-scientific fields. It is true that many of the economic applications of geology are so new and so constantly changing that they are not yet fully organized on a scientific basis; but this fact is merely an indication of the lag of science, and not of the absence of possibilities of developing science in such directions. There is today a considerable tendency among geologists of an academic type, whose lives have been spent in purely scientific investigation and teaching, to assume that anything different from the field of their activities is in some manner non-scientific, and therefore less worthy. Many economic geologists have been made to feel this criticism, even though seldom expressed openly. For the good of geologic science, this tendency seems to the writer extremely unfortunate. The young man entering the field of economic geology should be made to understand that his is the highest scientific opportunity; and that if parts of his field are not yet fully organized, the greater is his own opportunity to participate in the constructive work to be done.

Under war requirements many geologists were called upon to extend their efforts to bordering fields of endeavor. In some quarters these activities were regarded as non-scientific, and as subtracting from efficiency in purely geological work,--and yet out of this combined effort came a wider comprehension of new scientific fields, between the established sciences and between sciences and human needs. It is inevitable that in the future these fields, now imperfectly charted, will be occupied and developed, perhaps not by the men who are already well established in their particular fields of endeavor, but by coming scientists. In this light, it was a privilege for geologists to participate in the discovery and charting activities of the war.

Still another attempt to discriminate between scientific and non-scientific phases of geologic effort has been the assumption by certain scientific organizations with reference to standards of admission,--that work done for practical purposes may be regarded as scientific only if it leads to advancement of the science through the publication of the results. There is by no means any general agreement as to the validity of this distinction. On this basis, some of the most effective scientific work which is translated directly into use for the benefit of civilization is ruled out as science, because it is expressed on a typewritten rather than on a printed page.

While applied phases of the geologist's work may be truly scientific in the broader sense, it is undoubtedly easy in this field to drift into empirical methods, and to emphasize facility and skill at the expense of original scientific thought. The practice of geology then becomes an art rather than a science. This remark is pertinent also to much of non-applied geologic work in recent years. A considerable proportion of this empirical facility is desirable and necessary in the routine collection of data and in their description; but where, as is often the case, the geologist's absorption in such work minimizes the use of his constructive faculties, it does not aid greatly in the advancement of science.

Geology is by no means the only science in which there has been controversy as to the relative merits of the so-called pure and applied phases; but as one of the youngest sciences, which heretofore has been pursued mainly from the standpoint of "pure science," it is now, perhaps more than any other science, in the transition stage to a wider viewpoint. In the past there was doubt about the extension of chemistry toward the fields of physics and engineering, and of physics toward the fields of chemistry and engineering, and of both physics and chemistry toward purely economic applications; but out of these fields have grown the great sciences of physical chemistry, chemical engineering, and others,--and few would be rash enough to attempt to draw a line between the pure and applied science, or between the scientific and non-scientific phases of this work. This general tendency means a broadening of science and not its deterioration.

COURSE OF STUDY SUGGESTED

There are almost as many opinions on desirable training for economic geology as there are geologists, and the writer's view cannot be taken as representing any widely accepted standard. On the basis of his own experience, however, both in teaching and in field practice, he would lay emphasis on the fundamental branches both of geology and of the allied sciences,--general geology, stratigraphy, paleontology, physiography, sedimentation, mineralogy, petrology, structural and metamorphic geology, physics, chemistry, mathematics, and biology. After these are covered, as much attention should be given to economic applications as time permits. The time allowance for training, at a maximum, is not sufficient to cover both pure and applied science. Subsequent experience will supply the deficiencies in applied knowledge, but will not make up for lack of study of basic principles.

It is safe advice to a student wishing to prepare for economic geology that there is no royal road to success; that his best chance lies in the effort to make himself a scientist, even though he cover only a narrow field; that if he is successful in this, opportunities for economic applications will almost inevitably follow. To devote attention from the start merely to practical and commercial features, rather than to scientific principles, brings the student at once into competition with mining engineers, business men, accountants, and others, who are often able to handle the purely empirical features of an economic or practical kind better than the geologist. In the long run the economic geologist succeeds because he knows the fundamentals of his science, and not because he has mere facility in the empirical economic phases of his work. Of course there are exceptions to this statement,--there are men with a highly developed business sense who are successful in spite of inadequate scientific training, but such success should be regarded as a business and not a professional success.

Geology is sometimes described as the application of other sciences to the earth. This statement might be made even broader, and geology described as the application of all knowledge to the earth. In the writer's experience, the best results on the whole have been obtained from students who, before entering geology, have had a broad general education or have followed intensively some other line of study. Whether this study has been the ancient languages, law, engineering, economics, or other sciences, the results have usually been good if the early training has been sound. To start in geology without some such background, and without the resulting power of a well-trained mind, is to start with a handicap in the long race to the highest professional success. It follows, then, that intensive study of geology should in most cases not begin until late in the undergraduate course, and preferably not until the graduate years. Two or three years of graduate work may then suffice to launch the geologist on his career, but so great is the field, and so rapid the growth of knowledge within it, that there is no termination to his study. It is not enough to settle back comfortably on empirical practice based solely on previously acquired knowledge. Each problem develops new scientific aspects. It is this ever renewing interest which is one of the great charms of the science.

However, whether the student has a general training in geology, a specialized knowledge of certain branches, or takes it up incidentally in connection with engineering and other sciences, he will find opportunities for economic applications. The frequent success of the mining engineer in the geological phases of his work is an indication that even a comparatively small amount of geological knowledge is useful.

The writer is inclined to emphasize also the desirability of what might be called the quantitative approach to the subject,--that is, of training in mathematics and laboratory practice, which gives the student facility in treating geologic problems concretely and in quantitative terms. Geology is passing from the descriptive and qualitative stages to a more precise basis. For this reason the combination of geology with engineering often proves a desirable one. It is not uncommon for the student trained solely in the humanities and other non-quantitative subjects to have difficulty in acquiring habits of mind which lead to sufficient precision in the application of his science. He may have a good grasp of general principles and be able to express himself well, but he is handicapped in securing definite results. This does not necessarily mean that a large amount of time should be given to study of quantitative methods; exact habit of mind is more important in the early stages than expert facility with methods.

The teacher of economic geology finds his data so voluminous that it is difficult to present all the essential facts and yet leave sufficient time for discussion of general principles or for drill in their constructive application. It is difficult to lay down any rule as a guide to the proper division of effort; but from the writer's point of view, it is a mistake to attempt to crowd into a course too many facts. At best they cannot all be given; and in the attempt to do so, the student is brought into a passive and receptive attitude, requiring maximum use of his memory and minimum use of his reasoning power. Presentation of a few fundamental facts, combined with vigorous discussion tending to develop the student's ability to use these facts, and particularly tending to develop a constructive habit of investigation, seems to be the most profitable use of time during the course of training. The acquirement of facts and details will come fast enough in actual practice.

The variety, amount, and complexity of the data available in geology tend in themselves toward generalizations in teaching--toward the deductive rather than the inductive method. A certain amount of generalization is desirable, but its over-emphasis develops bad habits of mind on the part of the student, and requires radical readjustment of his ideas in subsequent field investigations. To retain a proper emphasis on inductive methods, it is necessary to limit the amount of data presented. Good results have been obtained by using the "case system," now common in the teaching of law--that is, by starting with a specific fact or situation as a basis for developing principles.

Another advantage in the restriction of data is the opportunity thus afforded for spending more time in the study of original reports rather than of the short textbook summaries. The student thus learns where the best primary sources of information are, how to find them, and how to extract essentials from them.

FIELD WORK

Field work is an essential part of any course of geologic training. Not only should it be taken at every opportunity during the regular school year, but no summer should be allowed to pass without geologic practice in the field. Opportunities for such work are offered in the summer field courses given by various institutions. In recent years it has usually been possible, also, for the student with elementary training to take part in summer geological survey work for state, national, or private organizations. In fact, after two or three years of geologic training, it is comparatively easy for the student to earn at such intervals during the year a fair fraction of his year's expenses.

The ideal arrangement, from the writer's viewpoint, would be about an equal division of time between indoor and outdoor study. The alternation from one to the other supplies a much needed corrective to clear thinking. It is impossible to bring all the subject materials into the classroom and laboratory; such study must inevitably be more or less deductive and generalized. If the student at frequent intervals is not able to acquire and renew a mental picture of field conditions, there is likely to be a faulty perspective even in regard to principles, and a considerable gap between the theoretical and applied phases of his knowledge. It may be possible in the classroom, for instance, to discuss faults in great detail with the aid of maps, diagrams, and pictures; and yet it is extremely difficult to get a real three-dimensional conception of the problems without actually standing on the ground.

SPECIALIZATION IN STUDIES

With the increasing size and efficiency of human operations has come an inevitable tendency to specialization. Where, in the past, the necessary geologic work might be passably done by the mining engineer, the local superintendent or operator, it is now being intrusted to specialists. Even within the more strictly engineering phases of the mining engineer's work, there is the same tendency toward specialization; his work is being divided up among the electrical engineers, the mechanical engineers, the hydraulic engineers, and others. The opportunities for geologic work, therefore, are distinctly in the direction of specialization. The student in determining the field he shall enter needs to take this fact into account and to prepare accordingly, but not at the sacrifice of the broad basal training. Only a small part of the specialization can be accomplished in college. The remainder will come with experience.

In the future there is likely to be increasing specialization among the different educational institutions in the phases of applied geology which are taught. Geographic location has a good deal to do with this tendency. Where an institution is located near a coal or oil field, it is likely, as a matter of course, to specialize to some extent in the application of geology to these resources. Or, the specialization may arise from the fact that the teachers have had special training in certain phases of applied geology, and such training naturally and properly determines the emphasis to be placed. Courses in engineering geology are finding a natural development in the leading engineering colleges.

In view of the fact that it is impossible for any one institution to cover all phases of applied geology, because of lack of time, and in view of the fact that even if this were attempted the results would be very unequal, because of the varied experience of teachers or because of geographic location, it would seem wise definitely to recognize these limitations and for each institution to play up the work it can do best. With freedom of migration among universities, a student by moving from place to place can thus secure any combination of specialized courses which best fits his requirements.

A DEGREE OF ECONOMIC GEOLOGY

There has been some agitation in recent years for standardization of courses in economic geology, and for the granting of a special degree in evidence of the completion of such a course. The principal argument for this procedure is that it would tend to insure a better average of training and would draw a line between worthy geologists and a host of ill-trained pseudo-geologists. The earth is so accessible, and its use so varied, that geology is handicapped perhaps more than any other science by persons who really have no valid claim to a scientific title.

The writer doubts whether a special degree in economic geology would go far toward improving this situation. Even if the courses were the same in different institutions, the manner of treatment and the ability of the teachers would be so varied that in the future, as in the past, anyone inquiring into the real standing of a geologist would be likely to consider his individual training rather than the degree attached to his name. There would be no guarantee that institutions not qualified to give the degree might not do so. However, the principal objection in the writer's mind to a degree of economic geology is the assumption that it is possible for anybody, in the present stage of knowledge, to formulate a standardized course adequate or best to meet the varied requirements. Considering the breadth and the variety of the field, any such attempt at standardization would have to be highly arbitrary. Once established, it would be a hindrance to the natural development of new courses to meet the ever changing requirements. When, if ever, the science of economic geology becomes fully organized, a standardized course may be possible. In the present stage of the science, more elasticity is required than seems to be possible in any of the courses proposed.

One of the purposes of the introduction of a degree of economic geology, to separate the sheep from the goats, may be accomplished in another way,--namely, by the establishment and maintenance of high standards of admission and high aims on the part of the various professional societies having to do with geology and mining. If this is done, membership in such societies may be regarded as evidence of sound training and achievement. To some extent this procedure may relieve the pressure on universities for uniformity of courses and degrees, leaving them free to develop in such manner as seems best. Scientific organizations, overlooking the entire field, are in a position to take into account the greatest variety of factors of training and experience in selecting their members. Failure of any university course to make men eligible for such recognition will obviously react on the course in a desirable way.

THE OPPORTUNITIES OF THE ECONOMIC GEOLOGIST

It has been the aim in this book to present a general view of the fields of activity of the economic geologist; and the list of chapter headings in itself summarizes the variety of his opportunities. The rapidly increasing use of earth materials promises far greater calls for geologic aid in the future than in the past. The profession is in its infancy.

Opportunities for employment are ordinarily found in three main directions--in educational institutions, in the federal and state geological surveys, and in private organizations. Connection with the United States Geological Survey excludes participation in private work, and in recent years even in teaching. In the state surveys there is ordinarily more latitude in this regard. In the educational institutions, it is rather the common procedure for the instructor to secure his field practice and experience through private agencies, or through part time connection with state surveys,--an arrangement with advantages to all concerned. The educational institution secures the benefit of the field experience which it cannot afford to provide, and is enabled to hold geologists at salaries far below their earning capacity. The geologist gains by the opportunity to alternate between office and field study, and to correct his perspective by the constant checking of theory with field conditions. The combination tends to keep the clearly scientific and the applied phases in a proper relative proportion; it minimizes the danger of drifting into purely empirical field methods on the one hand, and of losing touch with actualities on the other. Geologists devoting their attention solely to field work often complain that they do not have time to digest and correlate their results, nor to keep up with what others are doing. On the other hand, geologists without current field practice are likely to develop too strongly along subjective, deductive, and theoretical lines. The teacher gains in freshness and force in the presentation of his subject in the classroom, and the very effort necessary for presentation requires better analysis and coordination of his field observations. The private or state organization gains in this combination by drawing on the general and varied knowledge which has necessarily been accumulated for teaching and investigative purposes.

Temperament and circumstances will determine in which of these directions the student will turn. However, in view of the present natural tendency to be attracted by the large financial rewards in the commercial field, it may not be out of place to emphasize the fact that these rewards are perhaps more likely to be gained through perfected training and experience in state and national surveys and in educational institutions, than through early concentration in the commercial field. In any case, the financial side will take care of itself when sufficient knowledge and proficiency have been attained in any branch of the science.

The world is the geologist's laboratory; it is the only limit to his activities. The frontiers are near at hand, both physically and intellectually. There are few fields so attractive from the scientific standpoint. There are few in which the successful prosecution of the science can be of so much direct benefit to civilization and can yield such large financial rewards. If, in addition, the opportunities for travel and adventure are taken into account, what profession promises a more interesting and useful life?

So far we have discussed geology as a profession. It has proved its value also as a training for administrative and other public careers. The profession contributes its full share of men to these activities. The practice of geology deals with a wide variety of factors, and requires the constant exercise of judgment in balancing, correlating, and integrating these factors in order to reach sound conclusions. This objective treatment of complex situations is valuable training for the handling of human affairs.

ETHICS OF THE ECONOMIC GEOLOGIST

Ethical questions involved in the practice of economic geology have called out much discussion, and, in some cases, marked differences of opinion among men equally desirous of doing the right thing. In the plain choice between right and wrong, there is of course no difference of opinion. Unfortunately in many of the questions which arise the alternatives are not so clearly labeled.

The lure of discovery and quick returns always has, and doubtless always will, draw into the field large numbers of persons without sound ethical anchorage or standards. Fortunately, these are not the persons in control of the mineral industries; they are mere incidents in the great and stable business built up by legitimate demands for raw materials.

The view is sometimes expressed that the geologist should hold himself aloof from the business or applied phases of his profession, because of the danger of being tainted with commercialism. This argument would apply to the engineer as well as to the geologist. To carry such a procedure through to its logical conclusion would mean substantially the withdrawal of scientific aid from industry,--which, to the writer, is hardly a debatable question. Circumstances are trending inevitably to the larger use of geologic science in the commercial field. The problems of ethics cannot be solved by staying out. The economic geologist is rather called upon to do his part in raising the standards of ethics in that part of the field in which he has influence. This he can do by careful appraisal of all the conditions relating to a problem which he is asked to take up, and by refusing to act where questionable ethical standards are apparent or suspected. He must understand fully the purposes for which his report is to be used; merely as a matter of professional self-interest, there is no other course open to him. In a field in which there is so much danger from loose ethical conceptions, the premium on rigid honesty and nice appreciation of professional ethics is proportionately higher. The extreme care taken in this matter by acknowledged leaders in the profession of economic geology should be carefully considered by the young man entering the profession. There is a reason.

In other chapters reference is made to certain special ethical questions, such as the use of geology in mining litigation (pp. 349-355), and the necessity of the geologist's recognizing his own limitations (pp. 92-94), but no attempt has been made to cover the variety of such questions that may come up. It is safe to assume that no special ethical code can be made sufficiently comprehensive, detailed, and elastic to cover all the contingencies which are likely to be met in the practice of economic geology; nor is it likely that any such code, if attempted, would be any improvement on the spirit of the Golden Rule. Simple decency and common sense in their broader implications are essential to the practice of the profession.

INDEX

Abrasives, 267-270, 397

Abyssinia, potash, 112

Adams, Frank D., 367

Adirondacks, New York, graphite, 282
iron ores, 160, 162, 163, 171
phosphate from magnetic ores, 105-106
use of magnetic surveys in tracing iron rocks, 317

Ad valorem method of valuation of mineral deposits, 331-335

Africa, bauxite, 242
coal, 116
cobalt, 255
copper, 197-198, 205
tin, 260
_See also_ South Africa; North Africa; East Africa; West Africa.
Alabama, bauxite, 243, 245
graphite, 281
iron, 52-53, 160, 162, 163, 166-167

Alaska, antimony, 248
copper, 36, 41, 47, 49, 199, 200-201
gold, 222, 224, 229
silver, 234
tin, 261, 262

Algeria, antimony, 247, 248
gypsum, 283
iron, 156, 160, 161, 194
petroleum, 128
phosphates, 104, 105, 106
_See also_ North Africa.

Almaden, Spain, mercury ores, 256-257, 259

Alsace, potash, 111-113

Alsace-Lorraine, coal and iron of, under Peace Treaty, 401-402

Aluminum Company of America, 243

Aluminum ores, 241-246, 397
_See also_ Bauxite.

Alunite, 39, 41-42, 112, 114, 230

Anaconda, Montana, arsenic production, 250

Anaconda Copper Mining Company, manufacture of phosphate, 105
use of geology in development and exploration, 326-327

Anamorphism, defined, 27, 57

Anamorphism of mineral deposits, 26, 57-58

Anhydrite, occurrence in gypsum deposits, 284-285

Anticlines, occurrence of oil in, 141-142, 147-148

Antimonial lead, 246

Antimony ores, 246-249, 398

Apex law, 349-350, 353

Aplites, 35

Appalachians, barite, 274
bauxite, 245
graphite, 282-283
petroleum, 132, 135
pitchblende, 266
pyrite, 108
tin, 262
_See also_ under individual states.

Argentina, borax, 275
mica, 286
petroleum, 128
tungsten, 183

Arizona, asbestos, 271, 272
copper, 33, 38, 41, 47, 48, 198-199, 203, 204-205, 208, 314, 316
gold, 222
manganese, 175
molybdenum, 186,187
silver, 234
tungsten, 183
turquoise, 293

Arkansas, bauxite, 96, 243, 244-245, 246
diamonds, 292
fuller's earth, 279
hones, oilstones and whetstones, 269
phosphates, 105
zinc, 215

Arnold, Ralph, 134, 136, 149-150

Arsenic ores, 249-251, 397

Artesian wells, 73

Asbestos, 270-272, 398

Asphalt and bitumen, 56, 151-153, 397

Atolia, California, tungsten ores, 185

Atwood, W. W., 414

Australasia, cement, 87
coal, 116
gold, 222

Australia, antimony, 247
arsenic, 250
asbestos, 271, 272
bauxite, 242
bismuth, 252
coal, 115
copper, 197-198
gold, 41, 222, 224
iron, 154, 164, 165
lead, 210-211, 212
molybdenum, 186
phosphates, 105
silver, 232
tin, 260
tungsten, 183
zinc, 214-215, 216

Australia, laws relating to ownership of mineral resources, 343, 345

Austria, cement, 87
graphite, 280
mercury, 256, 257
molybdenum, 186
talc, 299
uranium and radium, 264
zinc, 214

Austria-Hungary, barite, 272
coal, 115, 116
iron, 160, 161
magnesite, 191-193
manganese, 174
silver, 232
_See also_ Hungary.

Austria-Hungary, commercial and political control of various
minerals, 64

Ball clay, 85, 398

"Bar" theory of formation of thick salt beds, 297

Baraboo, Wisconsin, quartzites of, 82

Barite, 272-274, 397

Basalt, 17, 19, 82, 90

Bauxite, 9, 50, 96, 241-246, 397

Bavaria, graphite, 280

Bawdwin Mines, Burma, lead and zinc, 209, 214

Beaumont Field, Texas, occurrence of oil, 148

Belgian Congo, cobalt, 255
copper, 205

Belgium, barite, 272
cement, 87
coal, 115-117, 127, 401
flint linings, 269
iron, 160-161
lead, 54-55, 210
millstones and buhrstones, 269
phosphates, 104
zinc, 54-55, 214

Belgium, commercial and political control of various minerals, 64, 280

Belle Isle, Newfoundland, iron ores, 52-53, 160, 166

Bergholm, Carl, 319

Bergstrom, Gunnar, 319

Bessemer processes of steel making, 158, 161

Bilbao, Spain; iron ores, 160, 170

Billingsley, Paul, and Grimes, J. A., 44

Bingham, Utah, copper and lead ores, 37, 42, 47, 199, 203, 204, 207,
208, 212, 314

Birmingham, Alabama, iron ores, 160, 162, 163, 166-167
_See also_ Clinton iron ores.

Bisbee, Arizona, copper ores, 47, 198, 204, 314, 316

Bismuth ores, 252-253, 397

Bitumen and asphalt, 56, 151-153, 397

Black Hills, South Dakota, gold ores, 228, 229
tin ores, 262

"Blue ground," occurrence of diamonds in, 291

"Bluestone," 84

Bohemia, uranium and radium ores, 265

Boise Basin, Idaho, monazite deposits, 289

Boleo, Lower California, copper ores, 201

Bolivia, antimony, 247
bismuth, 252, 253
borax, 275
copper, 206
nitrates, 103
petroleum, 128
silver, 232
tin, 261, 262-263
tungsten, 183, 184

Bolivia, commercial and political control of various minerals, 64

Bonne Terre limestone, Missouri, zinc ores, 217

Boone formation, Missouri, zinc ores, 217

Borax, 274-277, 397

Borax Lake, California, borax deposits, 276

Borneo, diamond dust, 268
platinum, 238

Bort, 267, 268, 398

Boulder batholith, Montana, ore-deposits of, 44

Boulder County, Colorado, tungsten ores, 184

Braden copper ores, Chile, 199

Brazil, chromite, 179
coal, 116
diamonds and diamond dust, 268, 292
graphite, 280
iron, 52-53, 162, 165, 167, 313
manganese, 174-175, 176
mica, 286
monazite, 288, 289
oil shales, 151
zirconium, 189-190

Brazil, commercial and political control of various minerals, 64

Briey district, France, iron ores, 161, 163
vanadium, 187

Brinton, Virginia, arsenic ores, 251

British Coal Commission, 367

British Columbia, laws relating to mineral resources, 344

British Empire. _See_ Great Britain.

British Guiana, bauxite, 242, 243

British South Africa, coal, 116

Broken Hill, New South Wales, lead and zinc ores, 209, 212

Bromine, 277-278, 397

Brooks, Alfred H., 404, 408

Brooks, Alfred H., and LaCroix, Morris F., 404

Buhrstones, 269

Building stone, 80-84, 88-90, 397

Bureau of Mines, 403, 406

Burma, lead, 209, 210, 212
rubies, 289, 292
silver, 233
tungsten, 183, 185
zinc, 214, 216

Burrows, J. S., 367

Butler, B. S., Loughlin, G. F., and Heikes, V. C., 44, 55, 230

Butte, Montana, arsenic in copper ores, 251
copper ores, 40, 47, 49, 198-199, 201-203, 207, 208
manganese ores, 177, 314
silver ores, 234, 314
use of placers in locating ores, 316
zinc ores, 215-216
zonal arrangement of minerals, 42, 44

Cadmium ores, 253-254, 397

California, antimony, 248
asbestos, 271
asphalt and bitumen, 152
basalt, 82
borax, 275, 276-277
chromite, 179
copper, 199, 204
diatomaceous earth, 269
fuller's earth, 279
gold, 222, 224, 227, 229, 308, 316, 342
granite, 82
graphite, 281
grinding pebbles, 268
magnesite, 191-193
manganese, 175
mercury, 40, 256, 257, 259
natural gas, 151
petroleum, 132, 133, 135, 137
potash, 112, 113-114
pyrite, 108
serpentine, 83
silver, 234, 308
tourmaline, 293
tungsten, 183

Campbell, J. Morrow, 185

Campbell, M. R., 121, 122, 366

Campbell, M. R., and Parker, E. W., 367, 370-371

Canada, arsenic, 250
asbestos, 270-271, 272
cement, 87
chromite, 179
coal, 115, 116
cobalt, 255
copper, 197-198
corundum, 268, 270
feldspar, 86
fluorspar, 193, 194
gold, 222
graphite, 280-281
grindstones and pulpstones, 269
gypsum, 283-284
iron, 52-53, 155, 156, 160, 165
magnesite, 191-193
mica, 286, 287
molybdenum, 186
natural gas, 151
nickel, 180-182
petroleum, 128
phosphates, 105, 106
platinum, 238
pyrite, 107-108
salt, 294
silver, 232, 234-235
talc, 299, 300
titanium, 190
zinc, 214, 215

Canada, laws relating to ownership to mineral resources, 343
use of magnetic surveys in tracing iron rocks, 317

Cananea, Sonora, Mexico, copper ores, 203

Cannel coal, 125

Cape Colony, South Africa, asbestos, 272

Capillarity, effect on ground-water level, 70
effect on petroleum migration, 142-143

Capital value of mineral resources, 64, 328

"Capping," of copper ores, 47

Carbonado, 268

Carey Act, classification of public lands under, 310

Carmel, New York, arsenic ores, 251

Casing-head gasoline, 139, 151

Caucasus region, Russia, manganese ores, 174, 176

Cement, 86-88, 397

Cementation, mineral products resulting from, 24

Cementing materials, source of, 25

Central America, cement, 87, 88
silver, 232
_See also_ Costa Rica, Guatemala, Panama.

Central Powers. _See_ Germany, Austria-Hungary.

Cerium ores, _See_ Monazite.

Ceylon, graphite, 280-283 mica, 286

Chalk, 83, 398

Chamberlin, T. C., 217

Chamberlin, T. C., and Salisbury, R. D., 415

Chance, H. M., 367, 368

Chert, use for abrasives, 267, 268, 270

Chile, borax, 275, 276
bromine, 277
coal, 116
copper, 197-199, 203
iron, 155, 161, 162, 164, 171
manganese, 176
nitrates, 100, 101-104
phosphates, 105, 106
potash, 112
silver, 232
sulphur, 109-110

Chile, commercial and political control of various minerals, 64, 261

China, antimony, 247-248, 249
arsenic, 250, 251
bismuth, 252
coal, 115, 116, 127, 154
iron, 154, 160, 164, 165, 171
petroleum, 128
salt, 294
silver, 232
tin, 260
tungsten, 183, 184

China, commercial and political control of various minerals, 64

"Chloriding" for silver ores, 314

Chrome (or chromite) ores, 178-180, 307, 365-366, 398

Clarke, F. W., 13, 17, 18

Classification of mineral deposits, 27-59
of mineral lands, 309-311
of mineral materials, adjustment of scientific to commercial names,
356

Clays, 18, 85, 91-92, 398

Cle Elum, Washington, iron ores, 58

Cleavage, 26

Cleveland district, England, iron ores, 161

Clifton-Morenci district, Arizona, copper ores, 38, 198

Climate, as a factor in exploration, 315
effect of in formation of bauxites, 246

Clinton iron ores, 9, 52-53, 163, 166-167, 218, 313, 317

Coal, conservation of, 365, 366-382
European international situation, 116-117, 386, 387, 393, 400-403
general economic and geologic features, 56, 115-127, 309, 397
reserves, 116, 360-361, 366-367

Cobalt district, Ontario, arsenic, 251
cobalt, 255
silver ores, 232, 234-235, 308, 316
use of coefficient to estimate future output, 322

Cobalt ores, 254-255, 398

Coeur d'Alene district, Idaho, lead-silver ores, 39, 45, 211, 212-213,
216, 234

Coke, 118-119

Colloids, content of in clays, 92

Colombia, coal, 116
emeralds, 289, 293
gold, 222
platinum, 238

Colombia, commercial and political control of various minerals, 64

"Colorado," 313

Colorado, arsenic, 250
asphalt and bitumen, 152
bismuth, 253
coal, 117
fluorspar, 194
gold, 222, 230
graphite, 281
lead, 211, 212
molybdenum, 186
oil shales, 150
petroleum, 133
silver, 234
tungsten, 183, 184
turquoise, 293
uranium and radium, 264-265, 266
vanadium, 187-188
zinc, 216, 219-220

Commercial and political control of mineral resources, 65, 387, 388
_See also_ under individual resources.

Common rocks, as mineral resources, 80-94

Comstock Lode, Nevada, silver ores, 235-236, 308

Congo. See Belgian Congo

Connecticut, basalt, 82
diatomaceous earth, 269
tourmaline, 293

Conover, Julian D., 12

Conservation, 359-382, 393-395
application of economic geology to, 1-2
of coal, 366-382
of common rocks, 81
of human energy, 362
international aspects, 362-363, 375, 376-377, 393-395
of petroleum, 137-139

Conservation Commission of Canada, 367

Contact metamorphism, 20, 24, 25-27, 36-37
_See also_ Igneous after-effects.

Contracts, classification of earth materials in, 356-357

Copper ores, 9, 36-50, 51-52, 55, 197, 209, 307, 308-309, 313-314, 318,
396

Cornwall, England, tin ores, 42, 260, 262, 263
uranium and radium ores, 264

Corocoro, Bolivia, copper ores, 206

Corundum, 267-268, 270, 398

Costa Rica, manganese, 176

"Cracking" processes for refining petroleum, 137, 139

Cripple Creek district, Colorado, gold ores, 230

Cuba, chromite, 179
copper, 197
iron, 8-9, 50, 58, 96, 155, 160, 163, 171-173, 313, 349
manganese, 175
nickel, 181
petroleum, 128

Cuyuna Range, Minnesota, manganese ores, 175, 177

Cycle, erosion or topographic, 6-7

Cyclic nature of ore concentration, 7-8, 47-48, 56, 169, 201, 205, 208,
325

Cyprus, asbestos, 271, 272

Dams, geologic problems involved in construction, 414

Davis, W. M., 408

Death Valley, California, borax deposits, 276

Degree of economic geology, 427-428

Denmark, cement, 87
chalk, 83
grinding pebbles, 268

Depletion of mineral deposits, as factor in valuation and taxation,
331, 337, 339

Depth as a factor in mineral deposition, 43, 49, 58-59

Diamond dust, 267, 268, 398

Diamonds, 289-292, 316, 317

Diatomaceous earth, 267, 269, 398

Diorite, 82

Dolomite, 23, 192

Domes, occurrence of oil in. _See_ Anticlines.

Domes, salt and sulphur, Gulf Coast, 110, 298

Drilling, exploration of mineral deposits by, 320-321

Drilling records, public registration of, 305-306

Ducktown, Tennessee, copper ores, 204

Dutch East Indies, natural gas, 151
petroleum, 128, 129
tin, 260
use of coefficient to estimate tin reserves, 322

Dutch Guiana, bauxite, 243

Dutch West Indies, phosphates, 105, 106

Dynamic metamorphism, 25-26

East Africa, mica, 286

East Indies. See Dutch East Indies.

Eckel, E. C., 404

Economic Liaison Committee, 406

Egypt, petroleum, 128
phosphates, 104

Eiserner Hut, 313

Electrical conductivity, use in exploration of mineral deposits, 319

Ely, Nevada, copper ores, 41, 203

Emeralds, 289, 291, 293

Emery, 267-268, 270, 397, 398

Emmons, W. H., 43

Empire, Colorado, molybdenum ores, 186

Energy resources, 115-153
accelerating production of, 64, 130-131, 361, 366-367

Engineering, application of economic geology to, 2, 413-419

England. _See_ Great Britain

Enrichment, secondary, 7-8, 25, 46-50.
_See also_ under Copper ores, silver ores, etc.

Epigenetic ore deposits, use of term, 32, 36

"Equated Income" method of taxation, 335-336

Erosion, relation to oxide zones, 47-48

Erosion cycle, description of, 6-7

Ethics, questions of, 430-431

Europe, coal and iron situation under terms of Peace Treaty, 400-403

Expert witnesses, use of geologists as, 349-355, 357-358

Exploitation of mineral deposits, functions of geologist, 326-327

Exploration of mineral deposits, 301-327
effect of ownership laws on, 347-349
effect of taxation on, 339-341
quantitative aspects of, 321-322, 324-326
relation to international conditions, 395-396

Extralateral rights, litigation affecting, 349-355

Extrusive rocks, formation of, 19

Federated Malay States. _See_ Malay States.

Feldspar, 16, 86, 268-269, 397

Ferro-alloy minerals, 156-158, 173-196, 307, 362-363, 365-366, 393-394,
397-398

Ferroboron, 275

Ferrocerium, 288

Ferrochrome, 178

Ferromanganese, 173-174

Ferromolybdenum, 186

Ferrosilicon, 195

Ferrotitanium, 190

Ferrotungsten, 182-183

Ferrovanadium, 187

Ferrozirconium, 189

Ferruginous chert, 167

Fertilizer minerals, 99-114

Field work for students of economic geology, 425-426

Flint linings for tube mills, 269

Florida, fuller's earth, 279
phosphates, 105, 107
titanium, 190, 191
zirconium, 189

Flowage, rock, 25, 26

Fluorspar, 193-194, 397

Foothill district, California, copper ores, 204

Formosa, petroleum, 128

Foundations, application of geology to, 413

France, antimony, 247, 249
arsenic, 250-251
asphalt and bitumen, 152
barite, 272
bauxite, 242, 245
cement, 87
chalk, 83
coal, 115-117, 127
coal and iron situation under Peace Treaty, 400-403
fluorspar, 194
grinding pebbles, 268
gypsum, 283
iron, 154, 160-162, 163, 166-167, 402-403
manganese, 176
millstones and buhrstones, 269
molding sand, 84
oil shales, 150
phosphates, 104, 105
potash, 111-113
salt, 294
talc, 299
vanadium, 187
zinc, 214

France, control of various minerals in other countries, 64, 104-105,
178, 180, 210, 215, 222, 238, 247, 261, 280
laws relating to ownership of mineral resources, 343
relative position in regard to supplies of minerals, 399

Franklin Furnace, New Jersey, zinc ores, 215-216, 220

"Freestone," 84

French Guiana, bauxite, 242

Fuel ratio of coal, defined, 120

Fuller's earth, 278-279, 397

Gabbro, 19, 82

Gale, Hoyt S., 111

Galena dolomite, Wisconsin, zinc ores, 217

Galicia, petroleum, 128, 129
potash, 112

Ganister, 84, 91, 195

Garnet, 267, 268, 270, 398

Gas, natural, 57, 151

Georgia, asbestos, 271, 272
barite, 273
bauxite, 243, 245
corundum, 270
fuller's earth, 279
marble, 83

Georgia granite, volume change in weathering of, 21

Germany, arsenic, 250-251
barite, 272-273
bismuth, 252
borax, 275, 277
bromine, 277, 278
cadmium, 253, 254
cement, 87
coal, 115-117, 127, 400-403
copper, 9, 52, 197-198, 206
fluorspar, 194
gypsum, 283
iron, 154, 160-162, 402-403
lead, 54-55, 210-211
lignites, 379, 402
millstones and buhrstones, 269
nitrates, manufactured, 101-102
petroleum, 128
potash, 111-112
salt, 294, 297
silver, 232
tripoli and rottenstone, 269
uranium and radium, 264
zinc, 54-55, 214-215, 216
zirconium, 189

Germany, control of various minerals in other countries, 64, 174, 183,
189, 198, 211, 215, 222, 232, 257, 261, 271, 288, 387
participation of government in mineral trade, 388
relative position in regard to supplies of minerals, 399

Geysers, 72

Gilbert, Chester G., 123

Gilbert, Chester G., and Pogue, Joseph E., 119, 134, 138

Gilpin County, Colorado, uranium ores, 266

Glacial geology, application to railroad building, 418
application to road materials, 91, 418

Glacial soils, 95

Globe, Arizona, copper ores, 198

Gneissic structure, 26

Gogebic district, Michigan, iron ores, 312, 318, 325-326

Gold, monetary reserves, 223

Gold Coast, West Africa, manganese, 176

Gold ores, 36-50, 51, 221-230, 308-309, 313-314, 397

Goldfield, Nevada, alunite, 41-42, 114
bismuth, 253
gold-silver ores, 36, 39, 230, 308

Gossan, 47, 109, 173, 313

Government ownership and control. _See_ Nationalization.

Governments, participation in mineral ownership and international
trade, 388-390

Granite, 17, 19, 82, 90

Graphite, 279-283, 398

Graphite Association, Southern, 405

Gravel, sand and, 84-85

Gray, F. W., 368

Great Basin, Nevada, covering of mineral deposits by lavas, 311-312
gold-silver ores, occurrence in a metallogenic province, 308
tungsten ores, 185

Great Britain, arsenic, 250
barite, 272
cadmium, 253
cement, 78
chalk, 83
clay, 85
coal, 115-117, 126, 127
fluorspar, 193-194
fuller's earth, 278-279
grindstones and pulpstones, 269
gypsum, 283
iron, 154, 160-161, 163
manganese, 176
salt, 294
tripoli and rottenstone, 269
uranium and radium, 264

Great Britain, control of various minerals outside of British Isles,
64, 101, 104-105, 132, 152, 165, 178, 181, 183, 198, 210, 214,
222, 225, 232, 242, 247, 252, 256-257, 260, 275, 280
income taxes on mineral properties, 337, 339
laws relating to ownership of mineral resources, 343
participation of government in mineral trade, 388
relative position, in regard to supplies of minerals, 399
tendencies toward nationalization, 346

Great Plains, lignite, 118
pumice, 268

Greece, chromite, 178-179
emery, 268, 270
magnesite, 191-193
zinc, 214

Greenland, graphite, 280

Gregory, Herbert, 407, 413

Grimes, J. A., and Billingsley, Paul, 44

Grinding pebbles, 267, 268, 270, 398

Grindstones, 269

Ground-waters, composition of and relation to commercial use, 73-75
distribution and movement of, 68-72
influence in deposition of ore deposits, 41-42
relation to military operations, 78-79, 408, 410-411
relation to rock slides, 78, 416-417
source of, 68

Ground-water level, description of, 70
relation to oxide zone, 48
relation to zone of weathering, 22

Ground-water supply, relation of geology to, 75-76

Guano, 104, 106

Guatemala, chromite, 179

Guiana, bauxite, 242-243

Gulf Coast region, lignite, 118
petroleum, 132, 135, 137
salt, 298
sulphur, 110
_See also_ Louisiana, Texas, etc.

Gypsum, 100, 283-285, 397

Haas, Frank, 367, 369

"Head" of underground water, 71-73

Heikes, V. C., Butler, B. S., and Loughlin, G. F., 44, 55, 230

Highway building, application of geology to, 90-91

Holland, cement, 87
commercial and political control of various minerals, 64
_See also_ Dutch East Indies, etc.

Homestake Mine, South Dakota, gold ores, 229

Hones, 269

Hoover, Herbert C., 322

Hot springs, relation to ore-deposits, 40, 258-259

Hot waters, evidence of formation of ores by, 37-41

Huancavelica district, Peru, mercury ores, 258

Hudson River, physiographic problems in tunneling under, 415

Hudson's Bay, possible diamond field, 317

Humus, 94

Hunan Province, China, antimony ores, 249

Hungary, antimony, 247
natural gas, 151
_See also_ Austria-Hungary.

Hydrosphere, 18

Hypogene ores, use of term, 32-33

Idaho, coal, 117
lead, 39, 45, 209, 211, 212-213
monazite, 289
phosphates, 105
silver, 234
zinc, 214, 216

Idria, Austria-Hungary, mercury ores, 257

Igneous after-effects, ore-deposits formed as, 19-20, 36-46

Igneous rocks, formation of, 19
mineral deposits associated with, 19-20, 34-46
principal minerals of, 14-16
proportions of principal types, 17
relative abundance of, 17
weathering of, 20

Illinois, clay, 85
coal, 115, 117, 126
fluorspar, 194
limestone, 83
petroleum, 132, 133, 135
pyrite, 109
sand and gravel, 85
tripoli and rottenstone, 269
zinc, 216

Illinois Geological Survey, cooperative exploration for oil, 147, 306

Income tax, application to mineral properties, 336-339

India, bauxite, 242

India, bromine, 277
chromite, 178-179
coal, 115, 116
corundum, 268
diamond dust, 268
gypsum, 283
iron, 154, 164, 165
manganese, 174-176
mica, 286
monazite, 288, 289
petroleum, 128, 129
platinum, 238
salt, 294
zirconium, 189

Indiana, coal, 117, 126
hones, oilstones and whetstones, 269
limestones, 83
petroleum, 133, 135

Interest rate, as a guide in conservation, 364
choice of for valuation purposes, 233
limiting effect on acquirement of reserves, 334

International aspects of mineral resources, 2, 383-404

International Coal Commission, 387, 393, 402

International trade, in common rocks, 80
in minerals, 383-388
participation of governments, 388-390

Intrusive rocks, formation of, 19

Iowa, flint linings, 269
grinding pebbles, 268
gypsum, 284
zinc, 216

Ireland, bauxite, 242

Iron and coal, situation of western Europe under terms of Peace
Treaty, 400-403

Iron and steel, metallurgical processes, 158-159

Iron and steel industry, possible establishment on west coast of
United States, 155, 165

Iron cap, of sulphide deposits, 47, 109, 313

Iron ores, anti-conservational effect of war, 365
attempt to estimate reserves of continents, 322
exploration of in Lake Superior region, 323-326
general geologic and economic features, 8-9, 28, 34, 36, 47, 50,
52-53, 55-56, 58, 96, 153-156, 158-173, 397
litigation concerning Cuban, 349
metallogenic provinces and epochs, 308-309
outcrops, 312-313
taxation of in Lake Superior region, 335
use of magnetic surveys, 317-318
world reserves, 162-165, 360-361

Itabirite, 167

Italy, asbestos, 271, 272
asphalt and bitumen, 152
barite, 272
bauxite, 242
borax, 275
cement, 87
graphite, 280
manganese, 176
marble, 83
mercury, 256-257
natural gas, 151
petroleum, 128
pumice, 268
salt, 294
sulphur, 109-110
talc, 299
zinc, 214-215

Italy, coal situation under Peace Treaty, 401
commercial and political control of various minerals, 64
relative position in regard to supplies of minerals, 399

Japan, arsenic, 250
cement, 87
chromite, 178-179
coal, 115, 117
copper, 197-198
gold, 222
graphite, 280
iron, 154, 160
manganese, 174
natural gas, 151
petroleum, 128
silver, 232
sulphur, 109-110
tungsten, 183, 185
zinc, 214

Japan, control of various minerals in other countries, 64, 105, 154, 247

Jasper, 167

Java, manganese, 176

Jerome, Arizona, copper ores, 41, 47, 198, 204-205, 314

Joachimsthal, Bohemia, uranium and radium ores, 265

Joint Mineral Information Board, 406

Joplin district, Missouri, cadmium, 254
lead and zinc ores, 54-55, 209, 211, 214, 215, 216-219

Juneau, Alaska, gold ores, 229

Kansas, gypsite, 284
natural gas, 151
petroleum, 132, 133, 135
salt, 294
zinc, 215

Kaolin, 85, 398

Katamorphism, defined, 27, 57

Katanga, Belgian Congo, cobalt, 255
copper ores, 205

Kennecott, Alaska, copper ores, 36, 41, 47, 49, 200-201

Kentucky, asphalt and bitumen, 152, 153
coal, 117
fluorspar, 194
marble, 83
petroleum, 133
sandstone, 84

Kimberley, South Africa, diamonds, 291-292

Knox dolomite, Tennessee, zinc ores, 219

Korea, gold, 222
graphite, 280, 282
iron, 160
molybdenum, 186
tungsten, 183

Lacroix, Morris F., and Brooks, Alfred H., 404

Lake Superior copper ores, 36, 52, 200, 206

Lake Superior copper, silver, gold ores, occurrence in a metallogenic
province, 308

Lake Superior iron ores, 8, 47, 55-56, 160, 162, 163, 167-170, 309,
312-313

Lake Superior region, iron ore exploration in, 317-318, 323-326

Land grants in United States, retarding effect on exploration, 349

"Land-plaster", 100

Laterites, 172-173

Laws relating to mineral resources, 342-358

Lawton region, Pennsylvania, coal, 117

Lead and zinc, Wisconsin, equated income method of taxation, 335-336

Lead ores, 36-50, 54-55, 209-213, 307, 308, 313-314, 361, 397

Leadville, Colorado, bismuth, 253
lead and zinc ores, 212, 216, 219-220

Leasing law, on public lands in western United States, 348

Leith, C. K., 323

Leith, C. K., and Mead, W. J., 45

Leith, C. K., and Van Hise, C. R., 56, 324

Lesher, C. E., and Smith, George Otis, 371, 372, 373, 375

Lignite, 118, 120, 122, 124
German development of, 379, 402

Lime, 82, 99-100, 397

Limestone, 15, 17, 23, 82-83, 89-90, 91

Lincolnshire district, England, iron ores, 161

Lindgren, W., 43

Lipari Islands, Italy, pumice, 268

Lithosphere, principal elements of, 13
principal minerals of, 14-16
principal rocks of, 16-17

Litigation, use of geologists in, 349-355, 357-358

Lode, application of legal term to diverse mineral deposits, 350

Long-wall system of coal mining, conservational aspect, 368
subsidence of overlying ground and resulting litigation, 357, 417

Longwy, France, iron ores, 161

Lorraine, iron ores, 52-53, 161-162, 163, 166, 364, 402-403
phosphate from Thomas slag, 104

Loughlin, G. F., Butler, B. S., and Heikes, V. C., 44, 55, 230

Louisiana, natural gas, 151
petroleum, 132, 133, 135
salt, 298
sulphur, 110

Lower California, copper, 201
magnesite, 191-192

Luxemburg, coal situation under Peace Treaty, 401
iron ores, 160-162, 163
_See also_ under Lorraine, iron ores

Madagascar, corundum, 268
graphite, 280-282

Magmatic segregation, mineral deposits thus formed, 34-35, 59

Magmatic waters, evidence of formation of ores by, 37-41

Magnesite, 191-193, 397

Magnetic surveys in tracing mineral ledges, 317-318

Magnetite deposits, 34, 171, 191, 317-318

Maine, feldspar, 86
granite, 82
tourmaline, 293

Malay States, tin, 260-261
tungsten, 183

Manchuria, iron, 160

Mandatory countries, exploitation of minerals in, 390-391

Manganese ores, 47, 55, 173-178, 314, 386, 398

Mansfield shales, Germany, copper ores, 9, 52, 206

Mantle rock, 22

Mapimi, Mexico, arsenic production, 250

Marble, 83, 89-90

Marbut, Curtis F., 95

Marl, 83

Marquette district, Michigan, iron ore outcrops, 312

Maryland, diatomaceous earth, 269
serpentine, 83

Marysville, Utah, alunite deposits, 114

Mashing, 25-26

Massachusetts, granite, 82
serpentine, 83

McCoy, A. W., 142

Mead, Daniel W., 69, 77-78

Mead, W. J., 245

Mead, W. J., and Leith, C. K., 45

Mehl, M. G., 144

Menominee district, Michigan, iron ore outcrops, 312

Mercury ores, 40, 255-260, 398

Mesabi district, Minnesota, concentration of siliceous iron ores, 156
exploration for iron ores, 313, 318, 324, 325

Mesopotamia, petroleum, 128-130, 137, 391

Mesothorium, 288

Metallogenic provinces and epochs, 308-309

Metamorphic cycle and its relation to classification of mineral
deposits, 27-28

"Metamorphic rocks," defined, 27

Metamorphism, relation to economic geology, 10
use of principles of in exploration
for mineral deposits, 319-320
_See also_ Katamorphism, Anamorphism, Contact metamorphism,
Dynamic metamorphism, Weathering, etc.

Metasomatic replacement, 24

Metcalf-Morenci district, Arizona, copper ores, 38, 198

Meteoric waters, influence of in deposition of ore deposits, 25, 41-42

Mexico,
antimony, 247-248
arsenic, 250
cement, 87
copper, 197-198, 201, 203
gold, 222
graphite, 280-282, 283
lead, 210-211
magnesite, 191-192
mercury, 256, 258
molybdenum, 186
natural gas, 151
petroleum, 128, 129, 137, 144
silver, 231-232, 233
vanadium, 188
zinc, 214-215

Mexico, commercial and political control of various minerals, 64

Miami, Arizona, copper ores, 33, 47, 48, 198, 203, 208

Mica, 285-288, 398

Michigan,
bromine, 277
copper, 199
grindstones and pulpstones, 269
gypsum, 284
iron. _See_ Lake Superior iron ores, Gogebic district, etc.
limestone, 83
salt, 294, 297

Michigan, taxation of iron ores, 335

Midcontinent field, petroleum, 132, 135, 137, 141, 146

Military geology, preparation of textbook, 407

Military operations, relation of ground-waters to, 78-79

Millstones, 269

Minas Geraes, Brazil, iron ores, 52-53, 162, 165, 167, 313

Mineral deposits,
classification and general features of origin, 27-59
exploration and development, 301-327
origin as a factor in economic problems, 29-31, 322-323
outcrops, 311-317
secondary concentration, 46-50, 54-57
_See also_ under Iron ores, Copper ores, etc.
zonal arrangement, 42-45

Mineral industry,
basis for popular interest in, 328
"social surplus" of, 330

Mineral lands, classification, 309-311

Mineral paints, relative position of United States, 397

Mineral provinces and epochs, 308-309

Mineral resources,
conservation, 359-382
general quantitative considerations, 60-66
international aspects, 383-404
laws relating to, 342-358
nationalization, 345-347, 375-376, 377-378, 382
political and commercial control, 65
relative position of the United States in regard to supplies, 396-400
valuation and taxation, 328-341
world movement, 383-388
world reserves, 65-66

Mineralogy, relation to economic geology, 3

"Minette" iron ores, 158, 161, 166

Mining law, 342-358

Mining methods, control of by government or owners in interests of
conservation, 355

Minnesota,
granite, 82
iron. _See_ Lake Superior iron ores, Mesabi district, etc.
manganese, 175, 177

Minnesota, taxation of iron ores, 335

Mississippi Valley, cadmium, 254
lead and zinc ores, 54-55, 108, 211-212, 214, 215-219, 308, 313

Missouri, barite, 273-274
cadmium, 254
lead, 209, 211
silica for refractories, 195
tripoli and rottenstone, 269
zinc, 214, 215, 217-218

Molybdenum ores, 185-187, 397

Monazite, 288-289, 398

Montana, arsenic, 250-251
copper, 40, 42, 47, 49, 198-199, 201-203, 207, 208
gold, 222
graphite, 281, 283
manganese, 175, 176-177
petroleum, 133
phosphates, 105
sapphires, 293
silver, 42, 234, 237, 314
zinc, 42, 216, 219

Monte Amiata district, Italy, mercury ores, 257

Morenci-Metcalf district, Arizona, copper ores, 38, 198

Mother Lode district, California, gold ores, 229, 308, 316

Munitions Resources Commission of Canada, 404

Nancy, France, iron ores, 161

National Academy of Sciences, 407

National Conservation Commission, 367

National district, Nevada, antimony ores, 249

Nationalization of mineral resources 345-347, 375-376, 377-378, 382, 388

Natural abrasives, 267-270, 397

Natural gas, 57, 151

Nebraska, potash, 112, 114

Netherlands. _See_ Holland, Dutch East Indies, etc.

Nevada, alunite, 39, 41-42, 114
antimony, 247, 249
bismuth, 253
borax, 275, 276
copper, 41, 199, 203
diatomaceous earth, 269
gold, 36, 222, 230, 308, 311-312
graphite, 281
grinding pebbles, 268
mercury, 357
oil shales, 151
platinum, 239-240
silver, 36, 38, 234, 235-237, 308, 311-312
tungsten, 183
turquoise, 293
zinc, 216

New Almaden, California, mercury ores, 259

New Brunswick, gypsum, 283-284

New Caledonia, chromite, 178-179 nickel, 180-182

New Cornelia, Arizona, copper ores, 203

Newfoundland, iron ores, 52-53, 160, 166
laws relating to ownership of mineral resources, 344

New Hampshire, fluorspar, 194
garnet, 268
mica, 287

New Idria, California, mercury ores, 259

New Jersey, arsenic, 250
basalt, 82
clay, 85
iron, 171
sand and gravel, 85
zinc, 215, 220

New Mexico, copper, 199, 203
fluorspar, 194
silver, 234
uranium and radium, 265-266
zinc, 216

New South Wales, Australia, bismuth, 252-253
coal, 115, 116
lead, 209, 210, 212
platinum, 238
zinc, 214, 216

New York,
arsenic, 250, 251
emery, 268, 270
garnet, 268
graphite, 281, 282
gypsum, 284
iron, 160, 162, 163, 171
limestone, 83
millstones and buhrstones, 269
petroleum, 132, 133
pyrite, 108
salt, 294, 297
sandstone, 84
talc, 299

New Zealand,
bismuth, 252
phosphates, 105
platinum, 238
tungsten, 183

New Zealand, laws relating to ownership of mineral resources, 343

Nickel ores, 34-35, 180-182, 307, 308, 318, 398

Nitrates, 99-100, 101-104, 386, 392, 398

Nonesuch beds, Michigan, copper ores, 52, 206

North Africa,
iron, 156, 160, 161, 164
lead, 210
phosphates, 104, 105, 106
potash, 112
zinc, 214-215

North Carolina,
coal, 117
corundum, 268, 270
emeralds, 293
feldspar, 86
garnet, 268
granite, 82
mica, 287
monazite, 288, 289
rubies, 292
sand and gravel, 85
sapphires, 293

Northern Plains, coal, 118

Norway,
copper, 197-198
molybdenum, 186
nickel, 180
titanium, 190
zinc, 214
_See also_ Scandinavia.

Nova Scotia,
gypsum, 283-284
saddle-reef gold ores, 41

Oceania,
mercury, 258
phosphates, 105, 106
tin, 261

Ohio,
bromine, 277
clay, 85
coal, 117
grindstones and pulpstones, 269
gypsum, 284
hones, oilstones and whetstones, 269
limestone, 83
natural gas, 151
petroleum, 133
salt, 294
sand and gravel, 85
sandstone, 84

Oil. _See_ Petroleum.

Oil shales, 56, 139, 150-151

Oilstones, 269

Oklahoma,
asphalt, and bitumen, 152
gypsum, 284
lead, 211
natural gas, 151
petroleum, 132, 133, 135
tripoli and rottenstone, 269
zinc, 215

Ontario, Canada,
arsenic, 251
cobalt, 255
corundum, 270
mica, 286
nickel, 34-35, 180-182, 308, 312, 318
platinum, 238, 239
silver, 232, 234-235, 308, 316
talc, 299, 300

Ontario, Canada, laws relating to ownership of mineral resources, 344

Onyx marble, 83

Open-hearth process of steel making, 158-159

Ore deposits. _See_ Mineral deposits.

Oregon, borax, 275, 276
chromite, 179
mercury, 257

Origin of mineral deposits, as a factor in economic problems, 29-31,
322-323

Outcrops of mineral deposits, 311-316

Ownership laws, effect on exploration of mineral deposits, 347-349
relation of geology to, 349-355

Oxide zones, 22, 46-50, 313-314
_See also_ under Copper ores, Silver ores, etc.

Pablo Beach, Florida, titanium ores, 190-191
zirconium ores, 189

Pacific coast, possible establishment of iron and steel industry, 155,
165

Pacific coast province, coal, 117

Palegeography, relation to economic geology, 4

Paleontology, relation to economic geology, 4

Palestine campaign, use of geologic data, 409

Panama, manganese, 176

Panama Canal, slides, 416-417

Parker, E. W., and Campbell, M. R., 367, 370-371

Peace Conference, use of geologists in advisory capacity, 356, 406

Peace Treaty, coal and iron situation of western Europe under terms of,
117, 400-403
effect of terms on valuation problems, 335
Silesian lead and zinc ores, 210, 214

Pearls, 289-292

Peat, formation of, 123-124

Pegmatites, 19-20, 35, 39

Peneplains, formation of, 6

Pennsylvania, basalt, 82
clay, 85
coal, 115, 117, 126
flint linings, 269
graphite, 281
iron, 171
limestone, 83
natural gas, 151
petroleum, 133
sand and gravel, 85
sandstone, 84
serpentine, 83
silica for refractories, 195
slate, 85

Persia, petroleum 128-130, 137, 391

Peru, bismuth, 252
borax, 275
coal, 116
copper, 197-198
mercury, 258
molybdenum, 186
nitrates, 103
petroleum, 128, 137
phosphates, 106
silver, 232
tungsten, 183
vanadium, 187, 188

Petroleum, 57, 127-150, 307, 310, 386, 396, 398

Petroliferous provinces, 149, 308

Petrology, relation to economic geology, 3

Philipsburg, Montana, manganese and silver ores, 37, 175, 176-177, 237

Phosphates, 99-100, 104-107, 397

Physiography, general discussion and relations to economic geology, 6-10
_See also_ Topography.

Physiography, relation to bridge building, 413
relation to Hudson River tunnels, 415
relation to railway construction, 418
relation to river and harbor improvements, 414

Pisolites, 172

Pitch. _See_ Asphalt.

Pittman Silver Act, 233

Placers, formation of, 51
gold deposits in, 227
_See also_ Monazite, Platinum, Tin, Tungsten, and other minerals.
use in tracing mineral outcrops, 316-317

Plasticity of clay, 92

Platinum ores, 51, 237-240, 386, 398

Plumbago. _See_ Graphite.

Pogue, Joseph E., 100

Pogue, Joseph E., and Gilbert, Chester G., 119, 134, 138

Poland, lead and zinc, 210, 214

Political and commercial control of mineral resources, 65, 387-388
_See also_ under individual resources.

Porosity of rocks, 69, 141

Porphyry copper ores, 197, 199, 203

Portland cement. See Cement.

Portugal, arsenic, 250
copper, 197-198, 204
pyrite, 107-108
salt, 294
tungsten, 183

Potash, 86, 99-100, 111-114, 386, 398

Precious stones, 289-293, 398

Primary ore deposits, use of term, 32

Primary ores, relation to depth, 49

Propylitic alteration, 39, 236

Protore, use of term, 33, 48

"Proximate" analyses of coal, 120

Public domain, laws relating to ownership of mineral resources on,
343-344

Pulpstones, 269

Pumice, 267, 268, 270, 398

Puzzolan cement. See Cement.

Pyrite, 100, 107-109, 307, 386, 397

Pyrophyllite, 299

Quartz, as geologic thermometer, 38
geologic occurrence, 16, 38-39, 43, 45, 47, 168-169, 196
production and use, 84, 267, 269

Quartzite, 84, 91

Quebec, Canada, asbestos, 270-272
magnesite, 193
mica, 286

Quebec, laws relating to ownership of mineral resources, 344

Queensland, Australia, arsenic, 250

Quicksilver ores. _See_ Mercury ores.

Radium ores, 55, 263-266, 397

Railway construction, application of geology to, 417-418

Rambler, Wyoming, occurrence of platinum, 239

Ransome, F. L., 33, 208, 230

Ray, Arizona, copper ores, 33, 47, 48, 198, 203, 208

"Red Beds" copper ores, 9, 206

Registration, public, of drilling records, 305-306

Regulus, 247

Reparations Committee, 387, 393, 402

Replacement, metasomatic, 24

Reserves of mineral resources, 65-66, 359-363, 393-395
_See also_ under individual resources.

"Resource cost" of coal, reduction of in interests of conservation,
334, 375

Rhode Island, coal, 117
graphite, 281

Rhodesia, asbestos, 272
chromite, 178-179

Ries, H., and Watson, T. L., 413

Rio Tinto, Spain, copper ores, 204
pyrite, 108

Road building, application of geology to, 90-91, 418

"Rock flour," defined, 95

Rock slides, 78, 415-417

Rocks, common, as mineral resources, 80-84

Rocky Mountain region, coal, 117
petroleum, 132, 135

Room-and-pillar system of coal mining, modification for conservational
purposes, 368-369

Rottenstone, 267, 269

Roumania, graphite, 280
petroleum, 128, 129

Royal Ontario Nickel Commission, 181

Royalties on coal, reduction of in interests of conservation, 334, 375

Rubies, 289, 291-292

Russia, asbestos, 270-271, 272
cement, 87
chromite, 178-179
coal, 115, 127
copper, 197-198
gold, 222
iron, 155, 160-161, 163
manganese, 174-176
mercury, 256, 258
oil shales, 151
petroleum, 128-120, 137
phosphates, 104, 106
platinum, 238, 239
potash, 112
salt, 294
zinc, 214

Russia, commercial and political control of various minerals, 64
laws relating to ownership of mineral resources, 343

Russia, Asiatic, vanadium, 187
_See also_ Siberia.

Saar Basin, coal of, under Peace Treaty, 401

Salisbury, R. D., and Chamberlin, T. C., 415

Salt, 294-298, 397

Salt domes of Gulf Coast, 298

Sand, 15, 84, 267

Sand and gravel, 84-85

Sandstone, 15, 17, 23, 84, 90, 267, 269

Santa Rita, New Mexico, copper ores, 203

Sapphires, 289, 291, 293

Sargasso Sea theory, of deposition of lead and zinc sulphides, 217

Saxony, bismuth, 252
tin, 262

Scandinavia, molybdenum, 386
nitrogen-fixation plants, 102

Schistose structure, 26

Schlumberger, C., 319

Schuchert, Charles, 144

Schultz, Robert S., Jr., 417

Scotland, magnesite, 191
oil shales, 150

Searles Lake California, borax deposits, 276
potash deposits, 112, 113-114

Secondary enrichment, 7-8, 25, 46-50
_See also_ under Copper ores, Silver ores, etc.

Secondary ore deposits, use of term, 32

Sedigenetic deposits, use of term, 51

Sedimentary mineral deposits, unsolved problems, 9, 53, 56

Sedimentary rocks, formation of, 22-24, 96
mineral deposits associated with, 23, 51-57
principal minerals of, 15-16
proportions of principal types, 17
relative abundance of, 16
weathering of, 23

Sedimentation, relation to economic geology, 2

Segregation, magmatic, 34-35, 59

Sericitic alteration, 39

Serpentine, 83

Seward Peninsula, Alaska, tin ores, 261, 262

Shale, 15, 17, 23, 85, 90

Shasta County, California, copper ores, 204

Shipping Board, 356, 406

Siam, sapphires, 289, 293
tin, 260
tungsten, 183, 184

Siberia, emeralds, 293
gold, 222, 226
lead, 210
vanadium, 187
zinc, 214

Silesia, cadmium, 254
coal, under Peace Treaty, 401
lead and zinc ores, 54-55, 210, 211-212, 214-215, 216-218

Silica, 195-196, 267, 269
_See also_ Quartz, Quartzite, Sand, Sandstone, etc.

"Silt" (fine coal), use of, 370, 371

Silver ores, 36-50, 55, 231-237, 308, 313-314, 397

Silver Reef, Utah, deposits, 55

Slate, 85, 89

Slides, earth and rock, 78, 357, 415-417

Smelting capacity of world, 61

Smith, George Otis, 310, 367, 403

Smith, George Otis and Lesher, C. E., 371, 373, 373, 375

Smyrna, Turkey, emery, 268

Soapstone, 299-300

Societies, professional, standards of admission, 421-422, 428

Soils, classification, 97
composition, 96-97, 99
origin, 94-96
use of fertilizer minerals on, 99-101
use of geology in study of, 95-98

Sound waves, possible use in exploration, 319

South Africa, asbestos, 271, 272
cement, 87
coal, 116
cobalt, 255
copper, 197-198, 205
corundum, 268
diamond dust, 268
diamonds, 289, 291-292, 316
gold, 222-226, 228
iron, 154,164
mica, 286
tin, 260
vanadium, 187

South Africa, laws relating to ownership of mineral resources, 343, 345

South America, cement, 87-88
coal, 116
lead, 210, 211
mercury, 258
zinc, 214
_See also_ under individual countries.

South America, laws relating to ownership of mineral resources,
343-344, 345

South Carolina, coal, 117
monazite, 288, 289
phosphates, 105, 107

South Dakota, gold, 222, 228, 229
quartzite, 84
tin, 262
tungsten, 183

Southern Graphite Association, 405

Southern Pacific Railway, litigation in regard to oil lands, 348

Spain, arsenic, 250
barite, 272
cement, 87
copper, 197-198, 204
garnet, 268, 270
iron, 154, 156, 160-161, 162, 163
lead, 210, 211-212
manganese, 174
mercury, 256-257, 259
phosphates, 104, 106
platinum, 238
potash, 111-113
pyrite, 107-108
salt, 294
silver, 232
sulphur, 109-110
zinc, 214-215

Spain, commercial and political control of various minerals, 64

Spiegeleisen, 173-174

Springs, 72

Spurr, J. E., 43, 64, 403

Stassfurt, Germany, borax, 277
bromine, 278
potash, 111-112, 113, 296-297
salt, common, 296-297

Steel. _See_ Iron and steel

Stone. _See_ Building stone, Common rocks.

Storage of coal, 376

Stratigraphy, relation to economic geology, 4

Structural geology, relation to economic geology, 5
use of principles of in exploration for mineral deposits, 319-320

Structures of rocks, relation to earth stresses, 5
relation to topography, 7

Subsidence of ground over mining operations, geologic study of, 357, 417

Sudbury, Ontario, cobalt, 255
nickel ores, 34-35, 180-182, 308, 312, 318
platinum, 238, 239

Sulphide enrichment. _See_ Secondary enrichment.

Sulphur, 99-100, 109-111, 397

Sulphur Bank Springs, California, deposition of mercury by hot waters,
259

Supergene ores, use of term, 32, 33, 48

Surface water supplies, 76-78

Surface waters, application of geology to use of, 414
relation to excavation and construction, 78-79

Sweden, cement, 87
iron, 154, 155, 156, 158, 160, 162, 163, 171
manganese, 176
phosphate from Thomas slag, 104
zinc, 214
_See also_ Scandinavia.

Switzerland, cement, 87
nitrogen fixation plants, 102

Syngenetic ore deposits, use of term, 32, 34, 51

Taconite, 167

Talc and soapstone, 299-300, 397

Tankage, use of phosphate content, 104

Tariffs, proposed, on mineral resources, 175-176, 179, 184, 192, 248,
257-258

Tariffs and duties, anti-conservational effect of, 362-363, 366, 375,
376, 393-394

Tasmania, bismuth, 252
platinum, 238
zinc, 214

Taxation of mineral resources, 1, 335-341

Tennessee, barite, 273
bauxite, 243, 245
copper, 204
flint linings, 269
marble, 83
petroleum, 132, 133
phosphates, 105, 107
zinc, 54-55, 216, 219

Terlingua district, Texas, mercury, 257, 259

Texas, asphalt and bitumen, 152
coal, 117
fuller's earth, 279
graphite, 281
gypsum, 284
mercury, 256, 257, 259
natural gas, 151
petroleum, 132, 133, 135, 148
salt, 298
sulphur, 110

Thermal metamorphism. _See_ Contact metamorphism.

Thermal waters, 72

Thibet, borax, 275, 276

Thomas process of steel making, 158, 161
use of slag for phosphate content, 104, 106

Tin ores, 36-50, 51, 260-263, 307, 322, 386, 392, 398

Tintic, Utah, silver ores, 39, 42, 235, 251, 253

Titaniferous magnetites, 34, 171, 191

Titanium ores, 190-191, 398

Tonopah, Nevada, gold silver ores, 38, 234, 236-237, 308

Topographic cycle, description of, 6

Topography, relation to mineral deposits, 7-9, 314-315
relation to rock structures, 7

Tourmaline, 290, 293

Training in economic geology, 420-428

Transvaal, Africa, asbestos, 272
diamonds, 291
gold, 222, 223-225, 228

Trap-rock, 82

Travertine, 83

Treadwell Mine, Alaska, gold ores, 229

Trenches, military, application of geology to, 408, 410-411

Trinidad, asphalt, 152, 153
petroleum, 128

Tripoli, 267, 269, 398

Tungsten ores, 51, 182-185, 386, 398

Tunis, phosphates, 104-106
potash, 112
_See also_ North Africa.

Tunnels, application of geology to construction, 414-415

Turkey, borax, 275
chromite, 178-179
emery, 268, 270

Turquoise, 290, 293

Tuscany, Italy, borax deposits, 275

Umpleby, Joseph B., 383

Underground waters. See Ground-waters.

United Kingdom. See Great Britain.

United States, abrasives, natural, 267-270, 397, 398
aluminum, 242-245, 397
antimony, 247-248, 249, 398
arsenic, 250-251, 397
asbestos, 270-272, 398
asphalt and bitumen, 152, 397
barite, 273-274, 397
bauxite, 242-245, 397
bismuth, 252-253, 397
borax, 275, 276, 397
bromine, 277, 278, 397
cadmium, 253-254, 397
cement, 87-88, 397
chalk, 83, 398
chromite, 179, 398
coal, 115-118, 126, 127, 366-367, 397
common rocks, 82-88, 397
copper, 197-208, 396
corundum, 267-268, 270, 398
diatomaceous earth, 269, 398
emery, 267-268, 270, 397
feldspar, 86, 397
ferro-alloy minerals, general, 154-158
fertilizers, general, 100-101
fluorspar, 194, 397
fuller's earth, 278-279, 397
garnet, 268, 260, 398
gold, 222-230, 397
graphite, 279-283, 398
grinding pebbles, 268, 398
gypsum, 283-284, 397
iron, 158-163, 166-171, 397
lead, 209-213, 397
lime, 82-83, 397
magnesite, 191-193, 397
manganese, 174-177, 398
mercury, 256-259, 398
mica, 286-287, 398
mineral paints, 397
molybdenum ores, 186-187, 397
monazite, 288, 289, 398
natural abrasives, 267-270, 397, 398
natural gas, 151
nickel, 181, 398
nitrates, 102, 398
oil shales, 150-151
petroleum, 128-150, 396, 398
phosphates, 104-107, 397
platinum, 238-240, 398
potash, 112-114, 398
precious stones, 290, 292-293, 398
pumice, 268, 398
pyrite, 107-109, 397
salt, 294-298, 397
silica, 195-196
silver, 231-237, 397
stone, 82-88, 397
sulphur, 109-111, 397
talc, 299, 300, 397
tin, 261, 262, 398
titanium, 190-191, 398
tripoli, 269, 398
tungsten, 183-185, 398
uranium and radium, 264-266, 397
vanadium, 18, 188, 398
zinc, 214-220, 398
zirconium, 189, 398

United States, control of various minerals in other countries, 64, 102,
129, 152, 163-164, 165, 175, 180-181, 184, 187, 189, 191, 198,
222, 232, 238, 243, 261
laws relating to ownership of mineral resources, 343-345
quantitative feature of mineral production, 60-66
relative position in regard to supplies of minerals, 396-400
tendencies toward nationalization of mineral resources, 345-346

United States Bituminous Coal Commission, 376

United States Bureau of Mines, activities in the war, 406
literature or international mineral relations, 403

United States Geological Survey, activities in the war, 406, 407
classification of mineral lands, 310-311
employment by, 428
literature on international mineral relations, 403

United States Shipping Board, 356, 406

Uranium ores, 55, 263-264, 397

Utah, arsenic, 250, 251
asphalt and bitumen, 152
bismuth, 253
copper, 37, 42, 47, 55, 199, 203, 204, 207, 208, 314
gold, 222, 314
lead, 42, 211, 212
manganese, 55
oil shales, 151
phosphates, 105
potash, 112, 114
silver, 42, 55, 234, 235
uranium and radium, 55, 264, 265
vanadium, 55, 187-188

Utah, ore deposits, relation to intrusive stocks, 44

Vadose zone, 70

Valuation of Lorraine iron ores at Peace Conference, 364

Valuation of mineral resources, 81, 328-341, 396

Value, capital, of mineral resources, 64, 328

Value of United States mineral production and imports, 62

Value of world mineral production, 62-63

Vanadium ores, 55, 187-188, 398

Van Hise, C. R., 367, 374

Van Hise, C. R., and Leith, C. K., 56, 324

Vein, application of legal term to diverse mineral deposits, 350

Venezuela, asphalt, 152, 153
magnesite, 191-193
petroleum, 128
phosphates, 105

Verde district, Arizona. _See_ Jerome district.

Vermilion district, Minnesota, iron ore outcrops, 312

Vermont, granite, 82
marble, 83
serpentine, 83
slate, 85
talc, 299

Virginia, arsenic, 250, 251
emery, 268
manganese, 175
millstones and buhrstones, 269
pyrite, 108
talc and soapstone, 299, 300
titanium, 190
zinc, 54-55, 219

Virginia City, Nevada. _See_ Comstock Lode

Volcanic ash, use as abrasive, 270

Wabana, Newfoundland, iron ores, 52-53, 160, 166

Wales, coal, 126

War, anti-conservational effects of, 365-366
application of geology to, 405-412
effect on ad valorem valuations, 335

War Industries Board, 356, 406

War Minerals Committee, 406

War Trade Board, 356, 406

"Wash," use in tracing mineral outcrops, 316-317

Washington, arsenic, 250
chromite, 179
magnesite, 191-193

Water, applications of economic geology to, 68
as a mineral resource, 61, 62, 67-79
general geologic relations, 67-68
hygroscopic, defined, 68
of constitution, defined, 68
quantity absorbed by soils and rocks, 69
relative abundance of, 18
source of, 67
use of, litigation arising from, 357-358
_See also_ Ground-waters, Surface waters, Hot waters, Meteoric
waters, Magmatic waters.

Water power, possibilities of substituting for coal, 378-379

Water supplies, 72-78

Water supply maps for military use, 411-412

Water table, defined, 70
_See also_ Ground-water level.

Waters, thermal, 72

Watson, T. L., and Ries, H., 413

Weathering, of igneous rocks and veins, 20-22
of igneous rocks, formation of mineral deposits by, 50
of mineral deposits, 46-50
of sedimentary rocks, 23-24
production of clay by, 91
production of soils by, 94-96
zone of, 70

Welfare work, in interests of conservation, 372-373

Wells, 72-73

West Africa, gold, 222
manganese, 176

West Indies, cement, 87
phosphates, 105, 106
salt, 294

West Virginia, bromine, 277
coal, 117
grindstones and pulpstones, 269
natural gas, 151
petroleum, 132, 133

Whetstones, 269

White, David, 128, 129, 140, 143, 146

White Signal district, New Mexico, uranium and radium ores, 265-266

Wisconsin, artesian wells, 73
diamonds in glacial drift, 292, 317
granite, 82
iron. _See_ Lake Superior iron ores, Gogebic district, etc.
quartzite, 82, 84, 195
zinc, 216

Wisconsin, equated income method of taxation, 335-336
taxation of iron ores, 335

Witwatersrand, South Africa, gold ores, 228

Wolfram ores. _See_ Tungsten ores.

Woodward, H. B., 69

Wyoming, chromite, 179
oil shales, 151
petroleum, 133
phosphates, 105
platinum, 239
potash, 112
uranium and radium ores, 265

Yellow Pine district, Nevada, platinum ores, 239-240

Yellowstone Park, springs and geysers of, 72

Zinc and lead ores, Wisconsin, equated income method of taxation, 335-336

Zinc ores, 36-50, 54-55, 213-220, 308, 313-314, 398

Zinc Syndicate, German, 215

Zirconium ores, 189-190, 398

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End of Project Gutenberg's The Economic Aspect of Geology, by C. K. Leith