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By Edward P. Barrett

The production of sponge iron is one of the earliest arts in the metal¬lurgy of iron and steel. The idea of producing iron direct from ore at temperatures lower than the melting point of, the iron has persisted throughout the centuries. The purpose of this paper is to present a general picture of the methods, proposed or tried within the past 100 years, for producing sponge iron by treating hot ore with heated reducing gases. The abundant literature has been abstracted, and quoted freely. Publications concerning more detailed information on the various methods are referred to in the footnotes and in the bibliography.

Jan 1, 1949

By Wesley A. Grosh

The Valzinco mine, Spotsylvania County, Va., is a lead-zinc deposit with minor quantities of copper. The property was reopened n 1942 by Panaminas, Inc. The Bureau of. Mines, in an effort to increase the reserves of the deposit to justify greater production, diamond-drilled nine holes totaling 4,213 feet during 1943. Drilling by the Bureau delimited the original ore body and discovered another ore body on the hanging-wall side, which was being developed by the company at the close of the project.

Jan 1, 1949

By Sol Weller

The Fischer-Tropsch synthesis consists of the formation of long-chain hydrocarbons by passage of carbon monoxide-hydrogen mixtures over metal catalysts, usually based on iron, cobalt, nickel, or ruthenium, at temperatures in the range 180°-300° C., and at pressures of 1-15 atmospheres. Although the reaction has been known and studied for more than 20 years, the mechanism by which it occurs is still poorly understood. One approach to understanding is to consider the effect upon the course of the synthesis of variations in each of the important operating variables. Consideration of the experimental data pertaining to these variables may suggest an over-all picture describing the synthesis - a picture which, in turn, would have to be consistent with all the known facts. The first part of this paper will be concerned with such a consideration of operating variables; the second portion will discuss recent work pertaining to the role of metal carbides as intermediates in the synthesis.

Jan 1, 1949

By J. A. Herdlick

At the request of the War Production Board a preliminary examination of the Big Ben molybdenum prospect near Neihart, Cascade County, Mont., was made by the Bureau of Mines under G. N. Bennett, mining engineer, Bureau of Mines Montana district office, in September 1942. Formal investigation, consisting of sampling, core drilling, and metallurgical testing, was later undertaken and completed in 1943. Field work was directed by Robert D. O'Brien, mining engineer, Montana district office, under the supervision of E. W. Newman, supervising engineer, Montana district office. This report describes the deposit, presents the factual data obtained from the sampling and core-drilling operations, and summarizes the results of the metallurgical studies. The deposit was first located and prospected in 1922 by the present owner, Frank Mansikka of Neihart, Mont. Periodic examinations made by responsible mining interests were culminated in 1938 when the Federal Mining & Smelting Co. optioned and investigated the property. No ores have been produced from the deposit to date.

Jan 1, 1949

By Th. G. Sahama

This paper contains some new heat-of-solution measurements of geikielite (MgTiO3), limonite (FeTiO3), fayalite (Fe2SiO4), and a natural forsterite in mixed acid (HF +HCl) and gives the results of a thermodynamic attack on the problem of stability of geikielite in rocks.

Jan 1, 1949

By Th. G. Sahama

This paper contains some new thermodynamic data for silicates in the series Mg2SiO4-Fe2SiO4 and MgSiO3-FeSiO3 and Lives the result: of a thermodynamic attack on the problems of stability end paragenoses. Although some data are lacking, satisfactory agreement with mineralogical and petrological observations is indicated.

Jan 1, 1949

By D. R. Torgoson, Th. G. Sahama

"This paper contains some new thermodynamic data for silicates in the series Mg2SiO4-Fe2siO4 and MgSiO3-FeSiO3 and gives the results of a thermodynamic attack on the problems of stability end parageneses.. Although some data are lacking satisfactory agreement with mineralogical and petrological observations is indicated.The use of thermodynamic methods in mineralogy and petrology has been rather limited, because accurate thermal data, especially for the more complicated and more important rock-forming minerals, have been too scanty to permit any systematic application to problems in those fields. It is, nevertheless, a fascinating task to investigate to what extent the mode of occurrence and the stability relations of the minerals and mineral parageneses, as revealed by petrological and mineralogical observations, agree with predictions of thermodynamics. At the present stage of development calorimetric data are needed for most of the abundant silicate minerals.Measurement of the heats of solution in hydrofluoric acid of minerals in the series Mg2SiO4-Fe2SiO4 and MgSiO3-FeSiO3 affords a ready means of obtaining their heats of formation from the oxides. Combination of such data with entropy and heat-capacity values gives a means of obtaining free energies of formation from the oxides, which, in turn, are connected di¬rectly with stability and paragenoses.The two silicates of magnesium, Mg2SiO4 and MgSi03, occur as rock-forming constituents as forsterite and clinoenstatite or enstatite. The orthosilicate (forsterite) forms a series of isomorphic mixtures with ferrous-orthosilicate (fayalite). The continuity of this series, suggested by petrological observations, has boon proved experimentally by Bowon and Shairer.4/ The present work shows that those minerals constitute a series of perfect solid solutions - that is, a series of solid solutions for which heats of formation from the individual pure silicates, Mg2Si04 and Fe2SiO4, aro negligibly small.The metasilicates of magnesium and iron also form an isomorphic series. However, this series differs from the forstorito-fayalite series in the fact that the most iron-rich mixtures, between about En10Fs90 and pure Fs, appear to be unstable with respect to the paragenesis iron-rich olivine plus quartz. The supposed instability of pure FeSiO3 as a crystalline compound, at least at high and at moderate temperatures, is remarkable, as no crystal struc¬tural reason for such instability is apparent. The present work indicates, also, that these minerals form a perfect series of solid solutions and throws additional light on the instability question.In the following, the samples used in this investigation will be described. For each of the natural olivines and orthopyroxenes, with the exception of sample L, a chemical analysis was made of the purified and actually used fraction. All the analytical work was carried cut by Oleg v. Knorring, and the specific gravity determinations, by moans of a pycnomctcr, by Oiva Joensuu, both of the University of Helsinki, Finland. The determinations of the optical properties were made by Mrs. Toini Mikkola, of the Geological Survey of Finland."

Feb 1, 1949

By S. Benedict Levin

In the spring of 1944, during the emergency In the supply of strategic mica, the Bureau core-drilled six aggregating 913 feet, at the Blister mica Trim. Cheshire County, N.H. These holes indicated a downward extension or the mica shoot which was being mined at that time and developed information essential for economic mining of the deposit.

Jan 1, 1949

By S. Benedict Levin

The Big mine has been a source of mica and high-grade felspar from separate zones in the same pegmatite dike since 1914. In 1943 it became the outstanding producer of strategic mica in New England. The urgent need for sheet mica led to core-drilling by the Bureau of Mines from February to May 1914. Nine diamond-drill hob's aggregating 1,474 feet in length were drilled by the Bureau of Mines with the objective of developing extensions of the known mica shoots. The use of large-diameter bits made it feasible to obtain reasonably reliable results in diamond-drilling this type of deposit.

Jan 1, 1949

By Richard L. Sayrs

The Eve Mills deposit is in Monroe County, Tenn., near the southeastern corner of the State. The deposit was examined in February 1943 by a Bureau of Mines engineer, and drilling the property was recommended to increase the on: reserves enough to justify mining should war needs require it. The deposits were explored, by 32 diamond-drill holes totaling 11,649 feet during the periods from July 1943 to November 7, 1945, and from April 1944 to August 17, 1944. The drilling campaign disclosed a large area of mineralization. The ore, however, is apparently confined to long, narrow sheets. The indicated grade of the ore bodies blocked cut by the Bureau of Mines is 4.o8 percent zinc and 2.10 percent iron.

Jan 1, 1949

By E. E. Maillot

In 1943, diamond drilling by the Bureau of Mines, comprising 11 holes which totaled 1,295.6 feet, showed that the pegmatite at Black Mountain consisted of shallow lenses in interbedded biotite-quartz-schist and impure quartzite. The average thickness of the pegmatite was 9.7 feet. Mineralization had a zonal arrangement. Beryl was most abundant near the footwall contact of the pegmatite. The average estimated beryl content of the pegmatite exposed at the surface was 0.81 percent, and the highest content of any pegmatite area was 1.75 percent. Other economic minerals were scrap mica, feldspar, spodumene, and lepidolite. Representative samples of the Black Mountain deposit failed to yield high-grade boryl concentrates by straight flotation owing to the presence of considerable spodumene. By employing heavy medium separation to remove the spodumene, 75.4 percent of the. BeO wan recovered in a flotation concentrate assaying 10.4 percent BeO.

Jan 1, 1949

By L. L. Hirst

Liquid fuel oils possess certain advantages over solid fuels. Ease in handling, precision temperature control, and almost complete freedom from ash are among those considered when a liquid fuel is selected for use in industrial processing. In some instances these fuels are desirable because more heating units can e packed in a Given space where space is limited, as on snips. In other cases the' are chosen because of lower actual cost per British thermal unit absorbed, or for control of the flame to increase the capacity of furnaces, as in steel and refining.

Jan 1, 1948

By H. E. Heide

The serious shortage of domestically produced asbestos during the war prompted the Bureau of Mines to investigate reported asbestos deposits in Alaska. The most promising' appeared to be these in the Cosmos Hills and Jade Hills areas along the Kobuk River in northwestern Alaska. The deposits along the west side of Shungnak River, a tributary of the Kobuk River, were the first to be investigated by the Bureau, in the summer of 1944. Four bulldozer trenches were excavated, from Which a 2-ton sample was taken. This sample was shipped to Rolla, Mo., for testing in the Bureau of Mines laboratory. In the summer of 1945 an investigation of asbestos deposits on Cosmos Creek, also a tributary of the Kobuk River, was begun; the work was completed during the field season of 1946.

Jan 1, 1949

By Clinton C. Knox

Attention of mine operators and engineers in the Picher zinc-lead field has been drawn increasingly in recent years to marginal ore deposits lying at greater than normal depth below surface in the marked structural depressions known as the Miami and Bendelari troughs. Not only mining but prospect and development drilling is relatively costly in the bottoms of the structural depressions known as the. Miami and Bendelari troughs which cross the center of the Picher field. Nevertheless, operations by various mining companies in recent years have shown that no insuperable problems exist, and with the gradual lowering of grade cut-offs throughout the field, certain potential deep-ore areas, previously only partly explored seemed worthy of further investigation. Some such areas were called to the attention of Bureau of Mines engineers by lease holders and operators, while others were noted in the course of Bureau's systematic investigation of Tri-State ore reserves. The writer was assigned to make a study of. those possible "trough extensions," in the course of which all available nine maps, drill logs, and prior reports were assembled. Subsequently 41 churn drill holes were bored by the Bureau in the periods October 1944 to May 1945 and October 1946 to April 1947. The general area under investigation this project is indicated on figure 1, which likewise shows its relation to nearby towns, roads, and railroads. The location of individual deposits included in the report is indicated more clearly on figure 3. Minable ore was found in only two holes, and the structural information procured by drilling was less encouraging than anticipated. This report, however, presents all factual data obtained, in the belief that they may be useful in subsequent prospecting and development projects in the areas investigated. There are also set forth some of the stratigraphic data relative to the Picher field ns a whole and the Miami and Bendelari troughs which were assembled in the preliminary investigation of this project.

Jan 1, 1949

By R. N. Roby

In the course of the Bureau of Mines investigations for suitable sources of high-aluminum clay for the production of alumina, the Whiteware clay deposit was examined in August 1942 by G.N. Bennett, mining engineer, Bureau of Mines, Montana District Office. This report presents the factual data obtained by the investigation, which also includes data on trenching and drilling, and the results of some refractory tests and chemical analyses of representative samples of the clay later taken from some of the best trench exposures and from adit dumps.

Jan 1, 1949

By H. P. Hermance

Preliminary examinations of the Parker and Webb deposits were made by E. E. Maillott, Bureau of Mines engineer in July 1942. The chemical and spectrographic analyses included in this report wore made at the Eastern Experiment Station of the Bureau of Mines at College Park, Md., under the general supervision successively of S. M. Shelton and of Paul M. Tyler, formerly regional engineer, Eastern Region. Beneficiation tests were conducted under the supervision of Frank D. Lamb. The mineral exploration was under the general supervision of J. D. Bardill, formerly district engineer. Acknowledgment is gratefully made to the St. Joseph Lead Co., in particular to John S. Brown and P. J. Mechin for their assistance. Special acknowledgment is made to the American Metal Co., Ltd., ,Ind to T. C. Moore for furnishing core-drill and assay data; to the Universal Exploration Co. and P. B. Jennings; and to the Northern New York Mining Corp. and C. H. Sprague for their permission to publish the core-drill dta. Excellent cooperation was given by Dr. W; M. Agar and C, L. Rogers of the Geological Survey.

Jan 1, 1949

By Harold E. Heide

Although the United States has been the largest consumer of tin, only a small quantity of tin was produced or. the North American Continent during peace times, and thy deficiency was made UP by foreign imports. Because the most important sources of tin wore cut off by the war with Japan, it became necessary to increase imports from South America and Africa and, if possible, develop domestic tin reserves. Most of the tin produced in North America has come from the Seward Peninsula, Alaska, and a substantial portion of this was produced from the Potato Mountain area. Tin was first identified as occurring in the Seward Peninsula by A. H. Brooks in 1900, when a part of heavy concentrates from Anikovik River and Buhna Creek, one of its tributaries, proved to be stream tin. 4/ His report was given considerable publicity by the daily press, and the first steamers north in 1901 carried a number of prospectors bound for the Seward Peninsula to search for tin. The deposits of stream tin on Buck Creek in the Potato Mountain area were discovered in the fall of 1901. 2/

Jan 1, 1949

By R. S. Sanford

The Claim Point chromite deposits are at tidewater near the southern tip of the Kenai Peninsula in southwestern Alaska, The United States Geological Survey had a field party in the region from July until September 1940 under P. W. Guild, assistant geologist; maps and geological data were assembled and made available to the Bureau of Mines. A preliminary investigation of the deposits at Claim Point by the senior author during July 1941 was followed by surface sampling and core drilling to determine the quantity and grade of the ere, The Geological Survey was represented at the project by George O. Gates, geologist. Cores were checked and the structural data revealed by drill cores were interpreted. The principal chromite deposits have been sampled and delimitated by trenching and core drilling. Other deposits were trenched and sampled but were too small or too low-grade to warrant core drilling.

Jan 1, 1949

By Haskiel R. Shell

Methods of chemical analysis of clays for the following constituents are presented: moisture, ignition loss Fe2O3, TiO2, P2O5, CaO, MgO, Na2O, K2O, total. carbon, carbonate carbon total sulfur, soluble salts, and soluble sulfate. In these procedures the attainment of accuracy has been the primary consideration sample was taken to insure accuracy, with ordinary precautions. The procedures may therefore be somewhat somewhat and will not be suited for routine work on samples for which the approximate analysis is already known and in which the need for accuracy is not very exacting. However, the method shod be as a set of detailed directions, that have been tested and shown to yield accurate results with clays and other aluminum silicate minerals. Among these minerals are clays of all types, bentonite bauxite, shale, brick; soil, calcined refractory, and sand. Although some of the methods are Unusual, no particular claim is laid to originality. The material was drawn frail many sources, put together and tested.

Jan 1, 1949

By R. S. Sanford

The Muir Inlet or Nunatak molybdenum deposits arc in the Glacier Bay district, Muir Inlet, miles northwest of Juneau. The deposits were examined by Bureau of Mines engineers, and the area was mapped by a field party of the Federal Geological Survey during the summer of 1942. 5/ The following year the Bureau of Mines began developing the deposits. A total of 217 channel samples were taken, and 2 diamond drill holes totaling 256 feet wore drilled. The samples were sent to the' Bureau's laboratories at Rolla, Mo. for beneficiation.

Jan 1, 1949