fluorspar, quartz, dolomite, and pyrites. There is also some amethyst, calcite, aragonite, kaolinite, and gypsum. The ores are cobalt, silver, and bismuth, with some copper pyrites, galenite, pitchblende, gummite, uranochalcite, and arsenic. There are similar deposits at Johanngeorgenstadt, Saxony. The mountain sides are filled with a network of veins. These veins contain tin and silvercobalt ores and their strike varies greatly. Where dolomite spar is found, the silver-cobalt ores contain pitchblende, as at Annaberg. In the Gottessegen mine the pitchblende occurs in the spar in pieces 2 to 3 inches in diameter. These mines are worked principally for bismuth ocher, but also for cobalt and nickel. In the quartzic cobalt-bismuth mines of Schneeberg, Saxony, are found bismutite and various minerals of nickel, silver, and arsenic. There is also some pitchblende, uranochalcite, troegerite, walpurgite, zeunerite, uranospinite, galenite, zincblende, and some copper compounds.. URANIUM DEPOSITS IN PORTUGAL. The following description of the uranium deposits in Portugal is given by Segaud and Humery: a The uranium-bearing zone lies in the area of massive granite that occupies nearly the entire northern part of Portugal between the Desert of Galice to Castello Branco and reaches into the provinces of Minho, Tras-os-Montes, and Beira. The richest part of the district is between the towns of Guarda and Sabugal, near the southern part of the granite area. The zone touches the outcrops of Cambrian rocks north of Guarda, the veins being especially rich in wolframite. The region of Villar-Formosa, however, is almost equally uraniferous. This zone appears also south of Guarda, where the granite forms a superficial mass thrown above the primary rocks by faulting. Apart from the uranium, the rocks of the region are much mineralized, showing deposits of galena, arsenopyrite, chalcopyrite, tungsten, and cassiterite. The uranium-bearing veins crop out in the granite, and also in the Cambrian schists. The granite is generally hard, firm, and little altered. In the vicinity of the veins it is altered, perhaps through mechanical action. The degree of alteration varies much at different points. In some places a remarkable parallelism of the veins in one or two directions is observed; in one instance the veins can be followed 8 miles, and in another, less important, for a considerably longer distance. The width of the veins varies greatly. Outcrops show a continuous succession of swellings and constrictions, and the vein in many places disappears completely, only to reappear several yards farther away. In the north of Belmonte a vein is 8 meters wide for a short distance, but such width is believed to be exceptional. A width of fromto 1 meter is more common. The filling of the veins is mostly pegmatite and aggregations of crystallized feldspar and quartz. In the district of Guarda the filling of several veins is largely quartz. The gouge is argillaceous matter, and may carry uranium. Autunite (uranium-calcium phosphate) is present in different forms, in small groups of square tables of an intense yellow color, in small plates, as a pure coating, or still oftener in bright yellow specks disseminated througha Segaud, and Humery, -, Deposits of uranium in Portugal: Ann. des Mines, ser. 11, vol. 3, February, 1913, pp. 111-119. 29659°-Bull. 70-14- 4 out rock of a dull yellowish color. In the clay part of the veins the uraninite is in places completely invisible and its presence is revealed only by the electroscope. There are, also, blotches on the surface of the granite, giving it an intense yellow color. Notwithstanding this color, the granite is always poor in uranium. The autunite is probably accompanied by uranyl-circite. Chalcolite of a beautiful emerald-green color is also present. The content of the veins varies enormously. At one place on an outcrop material was found carrying values of 4 to 5 per cent,a whereas the surrounding material carried no values whatever. Ore containing 2 per cent is excellent and that carrying 1 per cent is good average ore. The minimum limit for profitable exploitation is a content of 0.3 per cent to 0.5 per cent ore. The unaltered mineral has probably not yet been reached, except perhaps in a few places, and it is presumed that the mineral does not differ greatly from that in outcrops. The region of Guarda forms an elevated plateau having an altitude of about 2,700 feet. It is traversed by a railway from Pampilhosa to Villar-Formosa and from Guarda to Lisbon. The transportation to the railroad stations is by oxcarts, but the erection of an aerial tramway is possible. The main work has been done in the more important districts of the northeastern part of the region around Porto. The region contains numerous small hamlets from which laborers can be easily procured at small wages. The most important workings are those of the Compagnie de l'Urane, which employs 600 men. The average net cost per yard of drifts with a cross section of 3 by 4 feet is about $17, and the average net cost of 1 cubic meter of broken ore is about $20. The small mineral content of the ore makes treatment at the mine necessary. This treatment is entirely chemical, without previous mechanical concentration; the products are uranium oxide on one hand and sulphate of barium, rich in radium, on the other. The most important factory is at Baraçao, and is owned by the Compagnie de l'Urane. The radioactive barium sulphate is treated in the factories of Nogent. URANIUM ORES IN AUSTRALIA. Within the last few years several finds of uranium-bearing ores have been reported from Australia. These reports, apparently, have interested not only scientific men in Australia, but also the general public. One of these deposits is 80 miles east of Farina, a railroad station on the Great Northern line in South Australia, and lies between Mount Painter and Mount Pitt. Brown' states that the rocks of the district consist of coarse and fine feldspathic, siliceous, and micaceous granite, and gneiss, and also micaceous rocks, quartzite, and mica schist. The rocks are contorted in places and penetrated by dikes of coarse, pink colored, eruptive granite. Two of the prospect pits are on outcrops of iron oxide with cellular quartz and gossan, the whole having the appearance of an irregular lode. The uranium minerals, torbernite and autunite, are disseminated through the ore, and are also crystallized on the walls of the fissures and cavities in it. Uranophane and gummite occur sparingly. Fergusonite and some monazite are also present. Torbernite occurs on two of the other claims, and on still another both torbernite and autunite are disseminated through the rock and in seams. The extent and width of the ore deposit have not been determined. a The article does not state what these percentages indicate. They probably refer to U3O8. Another uranium deposit lies southeast of the one just described, about 20 miles east-southeast of Olary, on the railroad line from Petersburg to Broken Hill, South Australia. The ore occurs as a yellow and greenish-yellow incrustation and powder on the faces, joints, and cavities of a lode, which consists of titaniferous magnetite, magnetite, etc., and quartz in association with black mica. There are two of these lode outcrops, more or less parallel and 5 to 15 yards apart. The main outcrop can be traced for some 200 yards. The ore is reported to consist almost entirely of carnotite, with possibly some gummite. From the accounts published most of the ore is of a very low grade. A company has been formed for exploiting the ore and extracting the radium. VANADIUM FROM ORES OTHER THAN CARNOTITE. SAN MIGUEL COUNTY, COLO., DEPOSITS. Probably the largest deposits of vanadium that have yet been discovered in the United States are in southwestern Colorado between and close to Placerville and Newmire in San Miguel County. These deposits were visited by Ransome and Spencer in 1899 and their description, together with notes on the chemical analyses and composition of roscoelite by Hillebrand, was published in 1900.a Fleck and French have also described the deposits. Fleck and Haldane later published additional descriptions, with notes on mining operations. Hess, in 1912, published an excellent description of these deposits with notes on the possible origin, etc.a According to Cross and Purington, the country rock is composed of Jurassic and Triassic sediments. They have divided these into three formations, the Dolores below, La Plata above, and McElmo above the La Plata. The latter is composed of two heavy beds of light-colored sandstone, separated by a thin bed of limestone. The vanadium-bearing rock is the lower sandstone which probably consists of two beds with an unconformity between. That part above the unconformity is yellowish in color and that below is gray. These beds outcrop on both sides of Bear Creek, south of Newmire, at a height of about 50 feet above the creek bed. A chemical company with works at Newmire, Colo., and Primos, Pa., is mining these Bear Creek deposits. On the east side of the creek the workings are rather extensive. The ore is removed as found, although such a Hillebrand, W. F., and Ransome, F. L., On carnotite and associated vanadiferous minerals in western Colorado: Am. Jour. Sci., 4th series, 1900, vol. 10, pp. 124-144; U. S. Geol. Survey Bull. 262, 1905, pp. 10-14, 18-22. b Fleck, H., and French, S. W., Uranium and Vanadium: Quart. Colorado School of Mines, January, 1909. c Fleck, H., and Haldane, W. G., Preliminary report on the radioactivity of carnotite in southwestern Colorado: Quart. Colorado School of Mines, October, 1909. d Hess, F. L., Notes on the vanadium deposits near Placerville, Colo.: U. S. Geol. Survey Bull. 530, pt. 1, 1911, pp. 142-157. e Telluride Folio, No. 57, Geol. Atlas, U. S., U. S. Geol. Survey, 1899, p. 52. operations have resulted in the formation of large chambers. The mining is easy, as the sandstone roof is hard and easily supported. Beyond these chambers are several drifts. Mining at present is confined to the west side of the creek. There is an easy haul of about 2 miles from the workings to the plant, with a down grade all the way. The vanadium-bearing rock is a light to dull green fine-grained sandstone. Sometimes the color is quite dark. Occasionally splotches of carnotite are found in the cracks and fissures, but the uranium content is too small to be worth saving. As a rule the richest ore follows the apparent unconformity between the two sandstones. In places a shallow layer, dark in color and from one-half to one inch thick, lies close to the unconformity and is said to be rich in vanadium. This layer partly, at least, accounts for the origin of the vanadium in the sandstone above and below. The deposits are also found at Sawpit between Newmire and Placerville, on both sides of the Rio Grande River; in the canyon of Fall Creek which runs into the Rio Grande below Sawpit; on the east side of the Rio Grande both north and south of Placerville; and on both sides of Leopard Creek, which runs into the Rio Grande close to Placerville. The only ore being mined at present, however, is at Bear Creek. According to Hillebrand, a the green vanadium mineral to which the sandstone owes its color is not a chlorite notwithstanding its appearance, but is closely related to the mica roscoelite wherein the proportions of Al2O, and V2O, are reversed. A large proportion of the ore carries less than 1 per cent V2O,. The ore mined at Bear Creek has an average content of 14 per cent V2O5. Some of it contains as much as 2 per cent V2O, or even a little more. The thin layer, already referred to, at places carries more than 8 per cent V2O,. These low-grade roscoelite deposits can be mined at a profit, because they are large and easily worked. HUERFANO COUNTY, COLO., DEPOSITS. Vanadium ore has been recently discovered in Huerfano County, Colo. The Colorado Mining Corporation claims, six in number, are in the Culebra spur of the Sangre de Cristo Range in Huerfano County. The nearest railroad station is Russell Siding, about 9 miles distant. From this siding to within a short distance of the mines the wagon road is an abandoned railroad grade. The vein is said to be a welldefined fissure vein and has been opened up at different places on the surface for a distance of 2,500 to 3,000 feet. It is 1 to 4 feet in width. The lowest workings are about 25 feet deep with the best showing in a couple of shafts about 14 feet in depth. The vein was originally • Hillebrand, W. F., and Ransome, F. L., On carnotite and associated vanadiferous minerals in western Colorado: U. S. Geol. Survey Bull. 262, 1905, p. 21. worked for copper, but about a year ago it was found to contain vanadium. A number of assays show the following V2O, content: 2.63, 2.91, 6.25, and 7.35 per cent. The copper content is 2 to 4 per cent or a little more. One assay made upon a much larger sample than was used in any of the above determinations showed 4.5 per cent V2O. The ore is heavy, black, and banded and is probably gneiss impregnated with vanadium minerals. It carries much green material, some of which may be copper vanadate. In places the ore is rather yellow and assays are reported showing as much as 1.75 per cent UO, but none of the yellow samples we examined contained more than a trace of uranium. Two or three small outcrops carrying vanadium have been found within a mile and a half east of these claims. Five miles north is a thin vein from 1 to 2 inches thick called the Santa Rosa vein, which also is said to carry some vanadium. CUTTER, N. MEX., DEPOSITS. At Cutter in Sierra County, N. Mex., on the Atchison, Topeka & Santa Fe Railroad, deposits of vanadinite have been worked by the Vanadium Mines Co. The veins lie about three-fourths of a mile south of Palomas Gap and contain, in addition to vanadium, galenite, copper carbonates, barite, fluorite, and other minerals. They were visited by Hess in 1911. The mine has recently been abandoned and the plant removed. Some ore has been mined on the Widner claims during the past year, but it was shipped for the lead content only. EAGLE COUNTY, COLO., DEPOSITS. In Eagle County, Colo., 7 miles southeast of the town of Eagle, silver ore has been found that carries also vanadium. The Lady Belle mine is 400 feet above Brush Creek on the side of Horse Mountain. There are two tunnels, one about 25 feet above the other. The upper one runs about north and follows the strike of the ore body, the dip of which is 34° E. The lower tunnel runs at an angle to the upper one and then bends until it takes almost the same direction. It is in about 60 feet and the upper one about 40 feet. The ore is a dark-greenish sandstone similar in appearance to the darker types of roscoelite found at Newmire, Colo. It assays 25 to 1,000 ounces of silver to the ton. Much of the ore that is high in vanadium is low in silver, although this is not invariably true. The vanadium ore contains coarsely crystalline layers. The high-grade silver ore is more compact, usually darker, and has blue-black dots and splotches, due probably to silver bromide. Pieces of float ore rich in silver have been found near Horse Mountain, but no high-grade ore has a Hess, F. L., Notes on the vanadium deposits near Placerville, Colo.: U. S. Geol. Survey Bull. 530, pt.1, 1911, pp. 157-160. |