Mohave County miner and our mineral wealth., 1921-12-16
Special Effort to Aid the Mineral Industries

| the country is relatively poor in high grade deposits of some other impor tant allowing elements used in alloy structural steels, such as automobile .steels. The bureau conducted studies directed toward devising means fol utilizing extensive deposits of low, grade iron ores that can not be smelt, ed profitably by present methods These studies included investigations of the low-grade iron ores of the Birmingham, Ala, district, the man. ganiferous iron ores of the Lake Su- perior district, and the iron and steel situation in the Pacific Coast states.
 The cost of production of zinc, with the standard retort process, is now so high that it endangers the position of zinc as cheap metal. Plans have been formulated for an investigation of proposed methods for the electro thermic metallurgy of zinc, with a view to increasing the recovery of metal and loering productwion costs. The results of an investigation re- garding the losses of fines in the tail ings of zinc metals in the Wisconsin district indicate that the use of con- centrating tables of a certain type will greatly increase recovery. It is estimated that this practice would have added about $1,000,000 annually to the value of zinc output in this dis trict had it been in operation in 1917. Important results in the utilization of the low-grade and complex ores of copper, lead, silver and zinc, which constitute a great problem in the min eral development of Utah, Colorado and other Rocky Mountain states, are promised by the utilization of the chlo- ride volatilization process. The sul- phur dioxide teaching of porphyry copper ores of Arizona holds the promise of important developments for the mineral industry of the south west.
 As about one-quarter of the bitu- minous coal produced in the United States is used in industrial power plants, the waste of unburned coal and coke in the ashes from boiler plants has beein vestigated by the bureau. It has been possible to re- cover the greater part of the unburn- ed fuel by washing the ashes on a concentrating table. As a result of a study of coal washing problems in the state of Washington, one mine has built table washing plant to treat a pile of refuse amounting to more than one million tons, estimated to contain 100000 tons of recoverable coal of colSing quality.
 The bureau conducted. studies re- garding the use of liquid oxygen as an explosive. In cooperation with the Department of Agriculture an invest igation was made of the use of cellu- lose from corn cobs in the manufac- ture of dynamite. Investigations were conducted to determine the best and safest condition for the industrial use of 13,O00,00O pounds of picric acid, held as surplus by the War Depart ment. During the year the bureau called attention to the danger of us- ing certain low-grade foreign deton- ators, which had been coming into the country in large numbers.
 A universal gas mask has been de- veloped by the bureau for protecting the wear against all poisonous gas not exceeding 2 or 8 per cent con- centration in air where a safety lamp will burn. A fireman's gas mask has also been developed. A small gas mask for the use of train crews in railroad tunnels was devised. Inves- ,tlgatlons made in connection with the problem of ventilation of vehicular tunnels showed that from 20 to 30 per cent of the heat of the gasoline used as fuel for automobile engines IS lost In the form of unburned gases Tn the exhaust, due to improper car buretor setting.
 investigations at the Ceramic Ex- pertinent Station at Columbus, Ohio, indicate that some American claws will yield products closely approach ing the English china clay. At the same station it has been demonstrated that better graphite crucibles can be made with the use of domestic bond ing clay than haveshitherto been made with imported clays.
 During the year the bureau, in CO., operation with three of the largest seaboard coal exchanges, developed scientific systems of classifying ex- port coals into pools by systematic sampling and analysis to supersede the arbitrary classification used in wartime. Further progress was made in the investigation for preparing and utilizing Ignite, which constitutes the greater part of the nations fuel re- sources.
 The bureau completed work on prep aration and analysis of special alloy steels for the navy. A comprehensive report on recent developments in cleo