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By George W. Maynard

IN the course of an examination of some of the California hydraulie mines in November last, I visited the property of the Gold Run Ditch and Mining Company, near Dutch Flat, Placer County. This is one of the most important and extensively worked mines in the district. The gold occurs in the characteristic blue gravel, which averages 175 feet in thickness, the lower 40-60 feet being made tip of cement gravel, which resists the action of water, and can only be loosened by blasting. The specimen which I have the pleasure of laying before the members was presented to me by Mr. I. L. Gould, the intelligent superintendent of the mines, who informs me that he found it in the old river channel, about twelve feet above the bedrock. The flattened water-worn nugget of gold, about the size of a kidney-bean, is imbedded in blue cement gravel, around which quartz has crystallized. When found the projecting portion of the nugget was enveloped in quartz, the core of gravel and gold having only been discovered after breaking the lump of quartz. On the quartz there is a shell of cement. The specimen is a remarkable confirmation of the theory of the deposition of quartz from solution. DISCUSSION. DR. T. STERRY HUNT, in commenting upon this occurrence, remarked that it is in accordance with what we already know of the recency of some of the quartz of this region, and cited the microscopic

Jan 1, 1880

By S. E. Bretherton

THIS title introduces the subject I wish to describe to my fellow members, very few of whom, I hope, have ever had as much trouble with the smelting of ore containing much zinc, either in the lead blast furnace or the matting furnace, its circumstances have forced upon me: First, for several years in Leadville, Colo., after the sulphide ores containing zinc had been developed with greater depth and were sold to the interests with which I was connected for smelting in the blast furnace for the recovery of the lead, silver, and gold; then, in New Mexico and Arizona, where the principal source of ore supply for our custom smelter was from miners who sent most of their product in the form of concentrates, which we briquetted and smelted in the blast. furnace, producing a matte containing copper, silver, and gold, for which we were paid; together with some zinc and lead, which was penalized if in excess of a maximum base set by the refinery to which we sold our copper matte; last, but not least, my experience in Shasta county, Cal., where for the sake of recovering $13 per ton value in copper, silver, and gold, I have smelted ore containing as high as 40 per cent. zinc (the last. 18,951 tons smelted averaged 15 3/10, per cent. zinc) which we not only lost, but which it cost us money to lose.

Jan 8, 1913

By D. J. Coolidge, H. L. Sheakley

This paper does not deal with all sands used in the glass industry in Missouri; it covers only that used in the plate-glass factory at Crystal City. However, it is probably safe to say that other sands, pro- duced throughout the state for this purpose, are of identical nature. The glass sand used in Missouri is cornrnonly called the St. Peter deposit, which is ascribed to the Ordovician Rock series in the form of sandstone. This St. Peter deposit, aside from a few small outliers, covers a large area of eastern Missouri. It forms, through a broad curve, the northeast margin of the typical Ozark region between Cape Girardeau on the southeast and Mineola, Montgomery County, on the northwest. The belt is extremely irregular, varying from one to ten miles in width; its length is 150 miles in a straight line. The outcrop near the entrance to the Crystal City mine appears in the form of a sandstone bluff approximately 30 ft. high, running along Plattin Creek (Fig. I). Above the sand rock an overburden of Joachim limestone appears, which thickens to nearly 300 ft. and forms the hill commonly called Buck Knob. Test holes where drilled at various points and the drillers' log indicate that the St. Peter deposit ranges in thickness from 63 to 71 feet. Properties of the St. Peter Sand From an analysis of the glass sands of the St. Peter formation in Missouri, the follow-

Jan 1, 1948

By Jack Parker

The White Pine mine site lies five miles south of Lake Superior in Ontonagon County, Mich. Copper sulfide, mixed with some native copper, is mined by a room-and-pillar system from gently dipping Upper Kewee-nawan sediments. Depth of mining now varies from 700 to 1800 ft and the ore body continues to a depth of at least 3400 ft. An area roughly 21/2 miles square has already been mined. Mining height has varied from 61/2 to 22 ft. A rock mechanics program was set up in late 1963 to promote safety and mining efficiency. This note reports some of the findings. Rock Strength Compressive strength of small, dry specimens of sandstones, siltstones, and shales from the ore zone varies from 20,000 to 30,000 psi. This is intermediate between the softer coal mine sediments and the meta-morphic and igneous rocks of hard rock mines. Annual Cycle of Rock Failure Since 1963, every roof and pillar failure involving more than a few tons of rock has been examined and documented. Some 1500 stations have been installed for measuring convergence, -c1/1000 in., with Invar extensometers. At first it was thought that there was some kind of a cycle of roof failures; perhaps annual, perhaps even elated to the moon or to earth tides, but records (see

Jan 1, 1971

By Robert G. Peets

After 216 years, the end of operations at the Corn- wall mine can be foreseen within the next two decades. The story starts in 1732 when three sons of Wiliam Penn-John, Thomas, and Richard-deeded 9669 acres in the Province of Pennsylvania to a Joseph Turner, who assigned it to William Allen. In 1734 Peter Grubb, who had prospected for iron in the area, paid Allen £ 135 for 300 acres of this tract in what is now Lebanon County. In 1737 he was granted a warrant for 142.5 additional acres, which included three hills of outcropping magnetite described as "rich and abundant, forty feet deep, commencing two feet under the earth's surface." This seemingly inexhaustible reserve was to become one of the most valuable deposits in the U. S. before the ore-rich Lake Superior region was developed.

Jan 7, 1957

Iowa Geological Survey, Des Momes, Ia. George F. Kay, State Geologist A list of publications will be sent upon request Most of the papers of the Survey have been published in the Annual Reports, issued since 1892. Separates of the many papers in the Reports may be had for postage, except where they are out of print, and except for vol 1 (1892), 2 (1894) and 14 (1903), where no separates are to be had. Thirty-five Annual Reports have been issued up to and including vol 35 (1929). A charge, plus postage, is made for vols, 4, 5, 7, 8, 9, 10, 28 and 33, others will be sent free upon request, plus postage on from 2 to 6 pounds Space prohibits giving more than a general picture of some of the contents; vols 4, 5, 7, 8, 9, 10, 11, 12, 13, 15, 16, 20, 27, 32, contain, among others, papers on the geology of Iowa, by counties Vol. 19 (1908), 6 lb , contains a number of papers dealing with the peats and coals of Iowa, and has bibliographies of those subjects Vol 22 (1912), 6 lb , contains an annotated bibliography of Iowa geology Vol-24 (1913), 6 lb , contains the analyses of 16 Iowa coals Vol 28 (1917, 1918), price $1 50, 4 lb , completely covers the subject of gypsum in Iowa, and has a bibliography of the sub¬ject. Each volume carries an administrative report and a review of mineral production for the period covered In addition, Technical Paper 2 (1930), Studies of Iowa coals, will be sent free upon request Also a geological map of Iowa, and maps of Iowa showing the distribution of the glacial drift sheets throughout the state, have been issued and are available

Jan 1, 1933

By David White

THE submission of carefully prepared estimates of the oil reserves of the United States calls for no apology or explanation. In this country, petroleum is a rapidly wasting asset and an occasional appraisal of the amount remaining in the ground is a simple business procedure to safe-guard the general welfare and the prosperity of the republic. The rumored danger of failure, in the near future, of the foreign supply on which we depend in constantly increasing amounts makes the immediate review of our available reserves the more imperative. The Director of the U. S. Geological Survey, in March, 1921, requested the American Association of Petroleum Geologists to cooperate in the preparation of new estimates of the oil remaining in the ground. With the members of this cooperative committee, state geologists, regional geologists, consulting specialists, and geologists and engineers attached to many companies worked both independently and through sub-committees. The reports for districts, counties, fields, etc., after review by local or state committees, were discussed by the joint cooperative committee in conferences that, in some instances, were attended by the original compilers of estimates for the states or smaller areas. Finally the data were reviewed and the figures revised by the joint cooperative committee, so that the totals given in Table 1 represent the opinion of the committee, which was composed of F. W. DeWolf, W. E. Wrather, Roswell H. Johnson, Wallace A. Pratt, Alexander W. McCoy, Carl H. Beal, C. T. Lupton, G. C. Matson, K. C. Heald, W. T. Thom, Jr., A. E. Fath, Kirtley F. Mather, R. C. Moore, and David White, chairman.

Jan 6, 1922

By Lee Trudick

The secondary dispersion of copper, zinc and fluorine in A horizon soils was examined in Pope and Hardin Counties, IL, by sampling 122 sites along five traverses. Four of the traverses were taken above a deeply buried manto; a fifth intersected a vein complex exposed at the bedrock surface. Plants at each site were examined and analyzed for fluorine and on one traverse for copper and zinc. The A horizon soils were also tested for lead, manganese, barium, nickel and cobalt. The total content of copper, zinc, and other heavy metals in soils was determined by atomic absorption spectrometry (AAS) after acid bomb dissolution. Fluorine in soils was determined by fluoride ion-specific electrode after fusion with NaOH. Several cold- leach methods were also used. The analysis of A horizon soils for copper and zinc by AAS after acid bomb dissolution is a promising geochemical tool in the search for fluorspar. The acid bomb dissolution method is simple and takes little laboratoy time; it Produces a total dissolution of the sample with relatively little loss of the elements, and 20 elements can be analyzed from the same sample. In this study, the highest copper values were 80 times the local background level of 25 ppm and anomalies of this element tended to outline the fluorspar orebody better than either zinc or fluorine. The greatest zinc value was 15 times the local background level of 100 ppm, while the highest fluorine values were approximately four times the local background level of 165ppm.

Jan 1, 1982

By W. R. Ingalls

ThE following chronology presents the history of lead-mining in the United States in a brief form and is a useful reference in connection with the statistics of production: 1621.. Lead was mined and smelted near Falling Creek, Va., to supply the local demand for bullets and shot. This was the first mining and .smelting of lead in what is now the United States. 1632. In a report made on the minerals of New England, lead-ore is mentioned. (Bishop, I., 470.) 1650. Supposed beginning of mining by Jesuits in Pima county, Ariz. 1651. Grant of lead-mine at Middletown, Conn., to Gov. John Winthrop. 1682. Lead-ore supposed to have been discovered in Wisconsin by Nicholas Perrot. (K. D. Irving, Mineral Resources of Wisconsin, Trans., viii., 498.) 1700 Discovery of lead in Missouri by Penicaut, one of Le Sueur's party. Tile same expedition discovered lead near the southern boundary of Wisconsin in August of the same year. 1712. Grant by Louis XIV. of the Crozat patents, with special privileges respecting the discovery and operation of mines in the then territory of Louisiana. Little or no mining was done under this patent until about 1720. 1717. Transfer of Crozat patents to the Mississippi Co., promoted by John Law, which prepared for active mining. 1719. First attempt to mine and smelt lead in Missouri, made by Sieur de Lochon, in behalf of the Mississippi Co., near Meramec river. Results unsuccessful.

Jan 1, 1908

By Walter Voskuil

ILLINOIS supplies coal to seven states in the Upper Mississippi Valley -Illinois, Missouri, Iowa, Minnesota, Wisconsin, and portions of the Dakotas, Nebraska and Kansas. In this same area are marketed large quantities of coal from West Virginia, Kentucky, Pennsylvania, and else-where; fuel oil from the crude petroleum supplies of the Mid-Continent fields, and natural gas from Louisiana, Kansas and the Texas Panhandle. The boundaries of this "Illinois coal-market area" are determined by competition from other coal fields and from other forms of fuel. Within the area so described 90 per cent of Illinois coal is marketed. Thus in the Southwest, an abundance of fuel-oil supplies and natural gas domi-nates the market almost to the exclusion of coal. The westward move-ment of Illinois coal in Kansas, Nebraska and the Dakotas is met by an eastward flow of high-grade coals from Colorado, Wyoming and Montana. In the lake-shore counties of Minnesota and Wisconsin, the market is dominated by Appalachian coals, cheaply carried over the Great Lakes and reaching the ports of Lake Michigan and at the head of Lake Superior. Illinois coals find their largest market in the southern and western sections of these two lake states. Only small quantities of Illinois coals are shipped east of the state line. This market area is occupied entirely by the neighboring coal fields of Indiana and the Appalachian coal fields in Ohio, West Virginia, Kentucky and Pennsylvania.

Jan 1, 1936

By W. P. Blake

One of the most remarkable iron-ore districts of the world is found in Southern Utah, in Iron County, about 270 miles south of Salt Lake City, and 10 miles west of Cedar City. This region has long been known in a general way; but, being at present somewhat difficult of access, it has been rarely visited by 'any of our members. Professor Newberry has published somewhere a short description. Last year, by the invitation of J. R. Walker, Esq., of Salt Lake City, one of our associate members, I formed one of a party, including Professor G. W. Maynard and W. S. Keyes, to visit and inspect the region. A special car was placed at our disposal by the courtesy of Hon. John Sharp, Superintendent of the Utah Central Railway. From the present southern terminus of the road at Milford, a drive of 55 miles took us to Cedar City, about 10 miles east of the iron region. The ores outcrop in a low range of hills or mountains, and stand out in such bold relief from the general surface, and are so massive and jet black, that they may be seen for miles before they are reached. These outcrops extend in long lines over the hills, and mark very . clearly the course of the beds, conforming generally to the inclosing stratified formations, probably of Palaeozoic age. These rocks are somewhat obscure, but there are large outcrops of limestone without much alteration. This, in places, appears to be the adjoining rock, at others the wall-rocks are porphyry, and at others apparently a quartzite and a fine-grained felsite. The beds of iron-ore are from 10 to 100 feet and more in thick ness, and some of the outcrops extend unbroken continuously for 1000 feet and more. It consists chiefly of magnetite and hematite,

Jan 1, 1886

By Henry A. Mather

While this device is not new in its inception, its peculiar advantages failed to be of practical utility until furnace-builders instituted the mechanical reform of supporting the upper and lower water-jackets by hanging them from an I-beam frame, independently upheld by iron columns, instead of resting the entire weight of structure on the bottom, as practice formerly prescribed. The Colorado Iron Works were among the first to build copper-furnaces of this description, and the device, illustrated herewith, has been installed by them in three recent plants,—two furnaces for the Westinghouse interests near Ely, Vermont, and one for the Grand Prize Copper Company, of Gila county, Arizona. The jack-screw supports (Figs. 1 and 2) and the familiar iron bottom of former practice are retained as integral parts of this new furnace-bottom. And, instead of resting inert on the tapfloor of the furnace-room, the jack-screws are supported on and bolted to two I-beams the length of the furnace, placed immediately beneath, and parallel to, its sides. These I-beams are bolted to, and supported by, three steel axles equipped with small flanged wheels, the whole constituting a carriage, which runs freely on a track. The entire apparatus is movable or rigid at will, for the wheels are easily braced, if the tension of the tightened jack-screws does not serve to hold the whole in position. The advantages of this design will be at once apparent to those who have had practical experience in barring furnaces provided with stationary iron bottoms. It is a well-known fact that the larger part of the time occupied in cleaning and preparing a frozen furnace for active service is necessitated by working in a confined place where the temperature is uncomfortable, and that in such case the débris must be removed from

Jan 1, 1903

By C. Max Bauer

THE most important development in the petroleum industry in Montana, during 1924, was the bringing in of the Hepp well on May 12, by the Midwest Refining Co. This followed three years of active prospecting and drilling in the state by this company. The well is located 35 miles west of Billings, in Stillwater County, and makes a high-grade paraffin oil from the Dakota sand at a. depth of 3825 ft. After flowing for several months at the rate of 150 bbl. per day, the well has been shut in for lack of storage, awaiting further development in the field. TABLE 1. Production Cat Creek and Kevin-Sunburst Fields Month Kevin-Sunburst Pipe- Estimated Cat Creek Pipeline Estimated line Runs Fuel Oil Used Runs Fuel Used January 3,214 0 133,400 140 February 3,250 0 134,248 490 March 11,989 595 163,129 910 April 116,897 1,155 125,918 980 May 179,726 2,310 152,179 770 June 126,131 2,697 122,270 910 July 132,173 2,170 118,034 770 August 202,001 2,695 142,313 1,120 September 187,201 2,135 110,012 350 October 162,589 1,995 121,683 350 November 130,392 2,520 139,900 350 December 107,465 1,780 124,169 0 Total 1,363,028 20,052 1,581,255 .7,140 There are two producing oilfields in the state-the Cat Creek and the Kevin-Sunburst, which produced a total of 2,971,475 bbl. in 1924. The only other field of proved value is Soap Creek, which contains a heavy black oil and is shut in for lack of marketing facilities. Gas is produced for local use at Havre, Chinook, and Baker, and a carbon-black plant is located at Baker.

Jan 3, 1925

August 10 to 14, 1914, inclusive Headquarters will be at the Hotel Utah. The following program of the meeting has been arranged y the Local Committees: Monday, August 10.-Members and guests will register at the Secretary's desk in Room C-38, Hotel Utah, and receive the official badges, booklets and programs of the meeting. At 2:30 P. M., there will be an organ recital at the Mormon Tabernacle, after which members and guests will be taken for a trip around Salt Lake City in sight-seeing motor cars. At 8:30 P. M., the ladies will assemble in the lobby of the Hotel Utah, where they will be met by the members of the Ladies' Entertainment Committee, and will be taken for an automobile drive about the city. At 8:30 P. M., a technical session will be held in the ballroom of the Hotel Utah. The following papers will be presented: F. W. BACORN: An Amendment to Sales's Theory of Ore Deposition. C. W. GOODALE: Drumlummon Mine, Marysville, Mont. I. B. JORALEMON: The Ajo Copper-Mining District. STUART CROASDALE: Leaching Experiments on the Ajo Ore. FRANK R. VAN HORN: The Occurrence of Bournonite, Jamesonite, and Calamine at Park City. HOWLAND BANCROFT: Dip Chart. M. N. ALLING: Ancient Auriferous Gravel Channels of Sierra County, California. B. S. BUTLER AND H. D. MCCASKEY: Copper Ores of the New London Mine. GEORGE A. PACKARD: Rope Idlers in the Raven Shaft. ARTHUR CROWFOOT: Development of the Round Table at Great Falls. FREDERICK LAIST AND A. E. WIGGIN: The Slime-Concentrating Plant at Anaconda. W, L, AUSTIN: The Treatment of Copper Ore by Leaching Methods. W. L. AUSTIN: Leaching Copper Products at the Steptoe Works.

Jan 8, 1914

By Eckley B. Coxe

SINCE our last meeting, the Institute has lost, by the death of Mr. Gowen, one of its most distinguished members. I shall only attempt in this place to give a brief account of his many accomplishments and achievements; but our records would certainly be incomplete without a recognition of the important influence which he exerted upon the mining and metallurgical industries of this country, and a testimony to his private virtues of character. Although Mr. Gowen was best known as a great lawyer and as the head of a great railway corporation, he began his career, before he was of age, as the manager of a small anthracite blast-furnace at Shamokin, Northumberland County, Pennsylvania. He left this position, to engage on his own account in the mining of anthracite coal at Mt. Laffee, near Pottsville. This proved an unprofitable business, and, after the panic of 1857, he began the study of the law. As soon as he was admitted to the bar, he at once entered upon the active practice of his profession, and soon achieved an extraordinary success. In 1869 he was made President of the Philadelphia and Reading Railroad Company, and he afterwards organized the Pliladelphia and Reading Coal and Iron Company, the largest coalmining corporation in the world. He became a member of. this Institute during the first year after its organization, and remained a member until his death. He always took a deep interest in the work, and was prompt to co-operate by all means in his power in furthering the objects of the Institute. Mr. Gowen was one of the first to recognize the great importance to both miner and consumer, of the proper utilization of the small

Jan 1, 1890

By Stewart R. Wallace

Members of the Society, it is a very great honor for me to be here today and to have the opportunity of telling you about some things that have been accumulating in the back of my mind for some time. Before attempting to do so, I should acknowledge my debt to the many people who are responsible for my presence here this afternoon. To do this properly, however, would consume much of my allotted time and I will therefore mention only two men, both of whom were directly involved in the discovery of the Henderson ore body. The first of these was Robert Henderson, now dead, who at the time the work was going on was vice president of Western Operations of the Climax Molybdenum Co. Truly, he provided the environment that permitted the exploration program to function effectively, and the deposit appropriately bears his name. The second man I meant to mention was resident geologist at Urad at the time of the Henderson discovery. I think I should explain right here that the Urad ore body and the Henderson ore body, although entirely separate, are closely related deposits, and that both are located at Red Mountain in Clear Creek County, Colo.

Jan 6, 1975

By Persifor Frazer

At a time when all those interested in the iron trade are carefully scanning the horizon for new sources of the raw material, a few words concerning a field, which though not new, has not been hitherto fruitful of statistical information, may be deemed appropriate at this meeting. The district alluded to is the belt of the Middle James River, or in other words, that portion of the ferriferous belts of Virginia lying between Josua Falls and the little settlement of Norwood, in the counties of Amherst and Nelson, and on the left bank of the James River. This region shows unmistakable signs of developing a very considerable market for iron ores and for iron in the future, as well as a tempting appearance of possible productiveness in the former. It, is extremely hazardous to deal in generalizations as to the productiveness or non-productiveness of these measures without a more thorough development than has yet been attained. It is true that they probably constitute an horizon whence comes a part of the marvellous mineral wealth of the northern peninsula of Michigan. But

Jan 1, 1883

By Mack H. Shumate

1 Raw coal from Truax-Traer Coal Co.'s Burning Star Slope mine, Jackson County, Ill., is brought to the surface by the new 42-in. slope belt haulage conveyor at the rate of 850 tph. The loading system shown above employs four storage tracks, two tail tracks for loading, and four 25-hp hoists, operating in pairs, and coupled to two dolly cars to move the trains of cars through the tipple. The system has a capacity for loading 1800 tph. One operator is needed to load on each of two shifts. A third man working for a few hours on night shift sets up for the morning cycle. Railroad crews bring in empties placing them in the storage yard, twenty cars to the track. Trains of empties are pulled through to the tail track and loaded on the return; hoists at opposite ends pull the trains in each direction. [ ] 2 Pairs of hoist drums are interconnected electric- ally by a Trench lay cable buried between the tracks. When one hoist operates moving the cars, the tail hoist idles with brake released. The operator, situated in the tipple over the cars, views the storage yard at the end of the first shift (left). When returning loaded cars to yard, four or five cars are held on the dolly to couple the next string of empties. Empties are ready for loading on the tail track (right). Differing from a gravity system in which empty and load tracks are on a slight grade, this system is designed for 80 railroad cars for a two-shift operation and one rail service per day.

Jan 6, 1962

By R. J. Armstrong, J. J. McKay

The Montana Phosphate Products Co. is currently operating three underground phosphate mines in Powell County, MOnt. † In this area the Phosphoria formation is from 35 to 50 ft thick and contains a bed of phosphate rock varying in thickness from 2 1/2 to 5 ft, overlain by 12 to 30 ft of cherty quartzite, and underlain by about the same thickness of quartzite and shaly to cherty beds. In general, the phosphate bed has a reasonably hard quartzite footwall, as well as a hard cherty hanging wall, both of which greatly facilitate the mining operation. Folding has deformed the phosphate bed to a considerable degree in the area. It is carried to surface by several of the anticlines and lowered to considerable depths in some of the syn-clines. The main structural features affecting the mining operations of the company are the Garrison anticline and the adjoining syncline and succeeding limb of a second anticline on the east (Fig I). The axis of the folding strikes roughly northwest-southeast. The three mines, namely, the Anderson, Graveley, and Luke are on different limbs of the above folds. Accordingly, the dip of the bed, and consequently the mining method, in each mine differs to a considerable degree from that of the others. For this reason, each operation will be dealt with separately. Anderson Mine LOCATION AND DEVELOPMENT Topographically this mine is in a narrow valley, the bottom of which has an altitude of 5200 ft. The phosphate bed outcrops near the ridge on the east and dips towards the valley floor at an angle of from 25 to 30°,

Jan 1, 1950

By William T. Folwell

The Lucky Friday mine east of Mullan, Idaho, is an outstanding example of a property in the Coeur d’Alene district where a small and insignificant- appearing silver-lead-zinc vein at the surface has changed at depth into a large vein of great importance. The Lucky Friday vein has little if any surface expression and above the 1200 level the ore shoots are small and discontinuous. Between the 1200 level and 2450 level, the lowest developed level, the main ore shoot has shown remarkable improvement on each succeeding lower level, and today the mine is one of the major lead-silver producers in the Coeur d'Alene district. History: The Lucky Friday property is on the north side of the South Fork of the Coeur d'Alene River in sections 25, 26 and 35, T. 48 N., R. 5 E., Hunter mining district, Shoshone County, Idaho. This is about one mile east of the town of Mullan, which serves the eastern portion of the Coeur d'Alene district. The southern part of the property is crossed by a branch line of the Northern Pacific Ry. and by U. S. Highway 10. This highway is the principal road crossing the panhandle of Idaho and connects the district with Spokane, Wash., on the west and Missoula, Mont., on the east. The main portal and surface plant of the Lucky Friday mine is at an elevation of 3365 ft, only a short distance above the valley floor and a few hundred feet from U. S. Highway 10, so the mine is readily accessible for year-round operation.

Jan 12, 1958