As the production of molybdenum ores in the past in all countries has been relatively small, probably none of the deposits have been worked out and an increased output can be obtained. This applies particularly to the United States. All of the work that has been done so far has been on an experimental basis, and possibly the only mine whose tonnage will be decreased by past production is the Mammoth mine, near Mammoth, Arizona, and there is no certainty that this mine can not continue to produce as much for some time in the future as it did during its period of operation. Just what production can be obtained in the United States is somewhat uncertain, but it is probable that the deposits at Climax, Colorado, will yield at least one thousand tons of ore a day for several years and possibly for a good many years. The deposits of the Primos Chemical Co. near Empire, Colorado, are also extensive and should give a large output for some time to come. The rest of the deposits mentioned are small compared with these two, but the total production of all of them might be large, were a steady market assured and custom mills erected.

TREATMENT OF ORES

In concentrating wulfenite ores some form of table concentration, with the addition of slimers, is generally used. The metallurgical treatment of the concentrates varies and is still very much in the experimental stage. There is opportunity for the development of a process that will give the patentee a considerable advantage over competitors. The Bureau of Mines has been working on this problem and has recently devised a method that seems to be as efficient as any other and possibly has some additional advantages.

In the treatment of molybdenite the same methods are almost universally used. First the ore is crushed to the required fineness and the molybdenite is separated by flotation, largely oil flotation. The metallurgy of the concentrate, now more or less standardized, involves roasting the concentrate to the oxide and treating this oxide in an electric furnace for the production of ferromolybdenum. With small improvements, this practice is likely to be maintained for some time to come.

POLITICAL CONTROL

The political control of the molybdenum deposits of the world is determined by the geographical location. At present most of the known deposits are controlled by the United States and Great Britain, the latter controlling those in Canada and Australia. The British and Canadian governments actually have a government mill in Canada.

COMMERCIAL CONTROL

The Knaben mines, in Fjotland, the most famous and probably the only successful molybdenum mines in Norway, were acquired in 1905 by an English company, the Blackwell Developing Corporation. Later a newly organized Norwegian company, with head office in Christiania, took over the mines at a price of 2,500,000 crowns.

In Mexico the large molybdenum deposit in the Sahuaripa district of eastern Sonora is owned by George Fast, of Douglas, Arizona. The Lucky Tiger-Combination Gold Mining Co., of Kansas City, Mo., (American) owns the deposits in the Montezuma district. Another American company has acquired deposits near Poza, Sonora, about 20 miles north of Hermosillo. A deposit located 35 miles from the port of Topolabampo, northwestern Sinaloa, is owned by an American. The Compañia Minera Aurora y Anexas, operating molybdenum mines near Coyame and Marquez, northeastern Chihuahua, is owned by the Madero estate. The ore has been shipped to Leonard Worcester, El Paso, Texas, agent for the estate and also purchaser for L. Vogelstein & Co., New York, formerly a branch of the German metals combine.

In the United States, during the war the claim was made a number of times, both privately and in the press, that German interests were trying to obtain control of the molybdenum deposits of the country. This was due to the fact that the American Metal Co., which operates at Climax, Colorado, as the Climax Molybdenum Co., and which has some other molybdenum deposits, was formerly controlled by German interests. It is true that the majority of the stock of the American Metal Co. was owned in Germany, but Mr. Palmer, the Alien Property Custodian, took charge of this stock, and the affairs of the American Metal Co. were readjusted to changed conditions. The principal stockholders of the Primos Chemical Co. were four brothers by the name of Boericke. Before the war they had strong German connections, but outside of their deposits at Empire they made no special effort to get large molybdenum holdings in this country and did not seek to get a combination of any of the operating companies. The Primos Chemical Co. has since 1919 been taken over by the Vanadium Products Corporation, affiliated with the Bethlehem Steel Corporation. The Molybdenum Products Co., Denver, Colorado, which owns a part of the molybdenum deposit on the slope of Bartlett Mountain, near Climax, and operates a 200-ton mill, is a subsidiary of E. J. Longyear Co., exploring engineers, of Minneapolis, Minnesota. Both companies are owned by American stockholders.