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By AIME

Generally speaking, the mining industry had a good year in 1948 with most mineral products being produced in record quantities for peacetime standards. The big boys-iron and steel, coal, and petroleum-indicated the industry-wide trend by surpassing 1947 production figures. Although exploration and expansion are being pushed aggressively in all branches of the industry, there is a pronounced trend to engineering and research directed at cutting production costs, improving the product, and finding new markets. These improvement campaigns are making headway; in the bituminous coal industry, 5.43 tons per man employed is the new production record; 83 million tons of iron ore were unloaded at lower Lake ports, breaking another peacetime record; magnesium, due to improvement in manufacturing techniques, now competes on the market with aluminum.

Jan 1, 1949

By John V. Beall

Cutting costs and increasing safety with new ideas is the byword with The Cleveland-Cliffs Iron Co. on the Marquette Range in Michigan. Among the new ideas being tried out are mechanical shaft mucking, prefabricated lagging to replace timber poles, Carset bits in shaft sinking, and rubber tired guide wheels on the ore skips. Plans are being made to stockpile ore with conveyor belts during the winter. In sinking the Mather "B" Shaft a 3/8-yd clamshell-type bucket is used for mucking. The clamshell is opened and closed by means of a verticallymounted hydraulic ram actuated by 5000 psi oil pressure. An Ingersoll Rand-type hoist is used to raise and lower the clamshell. The hoist is controlled by one member of the crew on the floor of the shaft. When the bucket is raised, the men swing it over the muck pile to the desired position and then it is lowered on to the broken rock. The 1400-lb weight of the bucket causes it to sink into the broken rock and it digs as the ram closes the bucket. The hydraulic ram is operated by a man on the lowest shaft steel set who controls a specially designed oil pump which supplies oil pressure. The clamshell is emptied.

Jan 1, 1949

By John V. Beall

Let's start at the beginning, Mr. Turner. Where and when were you born? In Lansing, Mich., on July 31, 1880. And what was your education? I went to the University of Michigan, where I got an A.B. degree in 1902; then to the Michigan College of Mines at Houghton, graduating from there in 1904 with a B.S. and an E.M. What was your first job in the mining industry, Mr. Turner, and what were you paid? In the summer of 1902, 1 was a field assistant for the U. S. Geological Survey in southwestern Idaho and southeastern Oregon, working under Israel C. Russell, professor of geology at the University of Michigan, who incidentally, had just returned from an expedition to study the effects of the eruption of Mt. Pelee, on Martinique. I was paid $60 a month and found; in addition to doing geologic and hydrographic work, I cooked many of the meals for a party of four, and wrangled four horses. I slept for four months under the stars, without a tent.

Jan 1, 1949

By R. W. Diamond

Low-grade ores can be designated by two main classifications: (1) simple low-grade ores, and (2) complex low-grade ores. As a rule the first type has a relatively small metal content, although low- grade iron ores contain a rather high percentage of metal. As the simple type is the one that is ordinarily in mind when the term "low-grade ore" is used, the paper will be devoted mainly to ores in this general category. Cheap treatment is the prime requirement in utilizing low-grade ores of the simple type, although in some cases the value of nonmetallic by-products, such as limestone for fer- tilizer and silica for flux, allows a little more lati- tude than in the usual situation. When the costs are divided under the three headings-mining, milling, and smelting-it is apparent that the last group will not constitute an important factor as a rule because the high concentrating ratio makes the smelting cost per ton of ore fairly low.

Jan 1, 1949

By ALFRED T. BARR

In certain areas of the New Cornelia pit, considerable secondary blasting is necessary to reduce oversized boulders, formed from primary blasting, to pieces which will pass the 41/2-cu yd dippers on the shovels. Some of the boulders are 'dobied, but when time permits they are blockholed and blasted. In most instances one hole drilled to a depth of 2 to 3 ft and blasted with 1/3 to 1/2 of a stick of powder will break a boulder satisfactorily. Blockholing is normally done by using a jackhammer of the 55-lb class, 1-in. round drill steel, and detachable steel bits, 2-in. gauge when new. A bit change is usually made after the completion of each hole. The use of light drilling equipment in blockholing is desirable, both from the standpoint of safety and ease of doing the work, and when it was seen there was a possibility of using a lighter jackhammer through the use of tungsten-carbide bits and at the same time get at least the same drilling efficiency as with the standard equipment, it was decided to test tungsten-carbide bits. The claims for long life of the bits and footage drilled before resharpening gave hopes of eliminating much of the delay time in changing bits which is unavoidable with the use of steel bits. and thus gain in actual drilling time.

Jan 1, 1949

By D. W. Loucks

There is plenty of evidence to indicate that at least one of man's chief interests in life is to make himself as comfortable as possible. If you doubt this, just watch the fellow next to you for the next half hour trying to find the most comfortable position that a hard chair has to offer. Comfort, however, does not always mean an easy chair. To some, it may mean a wealth of money: to another, freedom from worry. But to most of us, it means first of all a comfortable atmosphere in which to live, and to a great many of us it probably also means freedom from that annoying task of firing the furnace. Today more than ever before, automatic heat is one improvement that is placed high on everyone's list. Perhaps this is because automatic heating is becoming relatively cheaper. Perhaps it is because of a good publicity campaign on the part of the oil and gas men or maybe it is just that we are getting lazier day by day. At any rate, almost every issue of Better Homes and Gardens, House Beautiful, or your other favorite home magazine carries an article extolling the virtues of this or that automatic heating system.

Jan 1, 1949

By G. J. Ballmer

Drilling and blasting 12-in. blastholes started about the middle of 1946 and has worked out so well that about one half of the blasting, formerly done with 9-in. holes, is now done with 12-in. holes. In most of this work the harder benches were chosen for the 12-in. size because these were the areas where the greatest difficulty was encountered in thorough fragmentation. At the start of this experimental work a 42-T Bucyrus- Erie churn drill was available whereas all other blasthole drilling was being done with 29-T rigs. The large drill was first equipped with a standard 9-in. string of tools but it could not drill quite as fast as the 29-T drills. How- ever, when the weight of the string was increased about 700 lb, or to a total weight of about 3500 lb, it was found that the 42-T exceeded the drilling speed of the 29-T by about 25 per cent. When a 12-in. bit was substituted for the 9-in. bit the 42-T rig again dropped behind the drill- ing rate of the 29-T rigs. At this stage of the experiment the 42-T was using a 12-in. bit with detachable points and the total weight of the string of tools was about 3800 lb. It took longer to change the drill points than it did the regulation bit and this accounted for some of the slower drilling rate. When a heavier stem and standard construction 12-in. bits were used it was found that the 42-T could drill a 12-in. hole slightly faster than a 29-T could drill a 9-in. hole even in the hardest rock in the pit.

Jan 1, 1949

By Carl S. Westerberg

Coal preparation practice and trends follow, among other factors, production trends in any given area. Considering an area the size of a state, some broad predictions may be made after a review of the annual production records. As this paper is concerned with coal cleaning in Utah, data on its production record are pertinent. Table 1 shows the percentage relation of coal production in Utah to the national total as a single figure up to 1935 which includes all recorded production. From 1935 through 1947 these data are presented by years. It is evident from these data that the production of Utah coal is ascending. The reason for this trend is industrial growth in the West resulting in a population shift which accounts for more people than the normal increase would supply together with Utah's relatively fortunate geographical location and its abundance of good-quality coal. Utah is also hopeful of supplying more coal in the future for West Coast power generati0n.l

Jan 1, 1949

By J. A. Brusset

THE Adanac mine was opened by West Canadian Collieries, Ltd. in 1943, and the question soon arose as to which system of haulage should be selected. Compressed-air locomotives and ropes were rejected on the ground of high cost. Since under the Alberta Mines Act the use of trolley locomotives underground in coal seams is not permitted, the choice lay between storage battery and Diesel locomotives, The preference of the author, who had experience with both in gassy French coal mines prior to 1930, was for Diesel locomotives due to lower cost of installation and greater flexibility and reliability. It was realized that the adoption of Diesels would be somewhat of an innovation since in the United States the mining laws prohibit their use under- ground in coal mines, and in Great Britain in 1943 their use was only in the incipient stage. By 1945, 25 Diesel locomotives were in use underground in gassy mines in Great Britain, and approval had been granted for the use of an additional fifty of two approved types also for gassy mines. Numerous special regulations of the British Coal Mines Act have been formulated to govern the use of Diesel locomotives. For instance, they are not allowed closer than 200 yards from the working face; daily inspections are required; and a weekly checkup and cleaning must be given the engine by a competent engineer. Also, methane content of the air in the roadway can never exceed 1.25 percent, and daily checks must be made if it exceeds 0.75 percent. Under Alberta regulations, we were required to use a flameproof type engine, to be used only in fresh air intake. The engine fumes had to travel along a separate ventilation split where no man was permanently employed. It is forbidden to run a

Jan 1, 1949

By E. J. ENGEL

The New York talc deposits of commercial importance are in St. Lawrence and Lewis counties, in the northwest Adirondack Mountains (Fig 1). All of the deposits are of pre-Cambrian age and occur within highly deformed and recrystallized marble of the Grenville series. The deposits in St. Lawrence County, near Gouverneur, are the largest and most productive of their type known in the Western Hemisphere. In 1948 the seven mines which are in operation will produce about 130,000 tons of ground talc. All talc production in Lewis County is from one mine. There the annual production ranges from 15,000 to 30,000 tons. These so called talcs of New York State include earth materials of differ- ent chemical and mineral compositions. In general the mineral talc is sub- ordinate in amount to other minerals in both the Gouverneur and Natural Bridge deposits.

Jan 1, 1949

By M. R. Geer

Coal washing assumed an important role in the mining industry of the Pacific Northwest long before washing practice became firmly established in the Appalachian field. A Scaife washer was operated in the state of Washington in 1887; and by 1927, the fist year for which complete statistics were compiled, nearly a third of the state's coal production was washed, in comparison with only about 5 pct for the country as a whole. Mechanical preparation was adopted in Alaska in 1922 in a plant constructed by the United States Navy at Chickaloon to provide bunker coal for naval forces operating in northern waters. Many of the coal beds mined in Washington and Alaska contained more impurities than those mined elsewhere, and this circumstance contributed to the early interest in mechanical cleaning. A much more important factor, however, was the inclination of the coal beds. With steeply pitching beds, hand sorting by the miner at the face is impossible; consequently, all material must be loaded and dealt with on the surface, just as is now proving the case with mechanical mining of flat beds. Thus "full-seam" mining afforded the same stimulus to the early development of coal washing in the Northwest that - it is providing under mechanization in the rest of the country today.

Jan 1, 1949

UNIVERSITY OF ALABAMA University, Ala Mining and Metalliaigical Society* G L Roberts, President T G Patterson, Vice-President B B Copeland, Treasurer K F Stark, Secretary G T Bator, Faculty Sponsor F H Crockard, Counselor

Jan 1, 1949

Jan 1, 1949

Jan 1, 1949

By Hewitt Wilson

CHALK is soft, pulverulent limestone formed from calcareous remains of microscopic organisms. Whiting is the powder made by the fine- grinding of limestone. Although European chalk dominated the early American market and is still shipped to the eastern and western seaboards, the domestic producer, by new technical processing, improved equipment, and proper selection and mixing of raw materials has shown that the United States can be independent of foreign sources. DISTRIBUTION European Chalk-Outcrops of Cretaceous chalk are found in the area roughly bounded by Antrim, Ireland, on the east, East Prussia on the west, Sweden and Scotland on the north, and Nice, France, on the south. Commercial chalk is mined from the chalk cliffs between Dover and Hull, England; from deposits near Mons, in the Departments of Pas de Calais and Nord in northern France; and from similar de- posits in Denmark and Belgium. United States-Some grade of limestone is found in every state of the Union, but true chalk of Cretaceous age is limited to three large areas in the central and southern states. Niobrara (Cretaceous) chalk outcrops are found as a narrow band encircling the Black Hills in South Dakota, Wyoming, and Nebraska, and in much larger exposures in southeastern South Dakota, eastern Nebraska, and western Kansas. A third chalk belt extends from west central Arkansas into Oklahoma and connects with the Austin beds, which almost cross Texas. In the southeastern states, the Selma chalk extends from western Tennessee south through northern Mississippi and turns east across central Alabama. Most of the domestic chalks are discolored with iron oxide or carbon. Some marls can be included with chalks of commercial possibilities. Some of the soft, cream-colored limestones of northern Florida, Georgia,

Jan 1, 1949

By W. D. Johnston, T. P. Thayer

THE minerals that collectively are known as chromite form an isomorphous series of the general formula (Mg,Fe) 0. (Cr,Al,Fe) 203. So wide is the range in chemical composition in this group that chrome ore consisting entirely of the mineral chromite may range from less than 30 pct to more than 60 pct Cr203. The most comprehensive published data on the chemical com- position of chromite are by Stevens,62 who made complete analyses of 52 samples of chromite concentrate from many localities in North, Cen- [ ] tral, and South America. These samples were mechanically purified to remove associated silicates and might be regarded as the cleanest chromite that could be obtained by any mechanical milling process. Fig 1 shows the predominant zone of isomorphism, within the triangular prism of composition defined by the mineralogical end members of the series, wherein his analyzed samples fell.

Jan 1, 1949

By Leon W. Dupuy

Many articles have been written describing peculiar and particular types of drilling. Little correlation has been made between the character of ground to be drilled and sampled and the type of drilling most desirable for procuring satisfactory samples. In development work, the engineer and metallurgist often desire the recovery of a sample in as physically natural a condition as possible, particularly when the sample must provide material for process tests as well as chemical and physical analyses. This paper describes the results of experimentation in drilling unconsolidated materials carrying titanium minerals in the Magnet Cove area, Ark. The drilling was most difficult in that the ground varied much in consistency, and it was vitally necessary to recover a physically natural sample. Ordinary churn drilling recovered a sample that could be analyzed chemically, but the sample was not in its natural state. The problem was successfully solved by utilizing and further developing methods used in the oil and clay industries.

Jan 1, 1949

By James K. Richardson

Today, the enigma of the "missing man" in the metal mining industry equals, and frequently surpasses in objective importance, the problems of ore development, drilling, sampling, pumping, milling techniques, geophysical prospecting, or any one of a hundred highly technical subjects. Unfortunately, as engineers, we have confined our attentions, in the main, to the scientific phases of mineral technology, relegating our man power problems to the background. But what good has all our scientific study and preparation been if we can't get the ore mined, milled, or smelted? What has happened to our labor supply? Where is the good old miner who could timber, drill a round, lay track, or do any job underground?

Jan 1, 1949

By John V. Beall

When a mine has ore averaging 5% lead, 7% zinc, 0.60% copper, 1/4 oz gold, and 6 oz of silver, adequate reserves, power and water, easy access to market, and is situated in beautiful natural surroundings with the advantages of a big city within a few hours drive, there is little left to be desired. Such a mine is the Mayflower mine of the New Park Mining Co. situated 30 miles from Salt Lake City in the Wasatch Mountains near Keetley, Utah.

Jan 1, 1949

By E. H. Rose

From the more distant members and some not so distant, the plaint is often heard that they cannot justify the expense and time required to attend the AIME Annual Meeting. Almost invariably, the reason given takes this form: "I just don't see that I would get enough out of it." Often the would-be clincher is added: "Besides, the meat of it all comes out in print anyway." Not long ago, a group of us who have seldom missed a meeting in recent years fell to discussing this phenomenon, and found ourselves in emphatic agreement that anyone holding such a belief indicates by his first remark that he does not know how to attend a convention, and by his second, proves it. He is, by and large, the man who has never been there, and of him, there are many.

Jan 1, 1949