What are the Applications of Xanthates to Flotation

Most papers on xanthate have dealt with principles rather than practice. On the assumption that many millmen are interested in knowing where and in what manner the xanthates are being used in mills other than their own, this paper will summarize the results of a recent survey of North American plants. A brief background story … Read more

Physical Metallurgists

During the past year there have been a number of significant investigations that have furnished evidence on the driving forces governing grain growth and on the role played by boundary impurities. Thus Burke has shown that in high-purity alpha brass the rate of grain growth in the earliest stages is approximately inversely proportional to the … Read more

Acid Mine Water Drainage

Acid mine-water drainage is a serious problem with many mines in the Tri-State zinc and lead mining district. Particularly is this true when large volumes must be considered in unwatering old mines that have refilled with water which has dissolved the products of oxidation and has become chalybeate in character. Original Mining Results in Oxidation … Read more

Metal Aging

The correlation of property changes during precipitation with structure has progressed, sometimes rapidly but other times more slowly, since the fundamental discovery of Merica, Waltenberg and Scott. The predominant factor that hampered the progress has been limitations imposed by the various detection methods. Refinements in X ray diffraction techniques and in metallographic methods, which have … Read more

Phosphate Rock

Apatite, the most abundant crystalline phosphate mineral, is found in igneous rocks and probably is the primary origin of all other phosphates, whether mineral or organic. Its chemical formula may be expressed as Ca5(Cl,F) (PO4)3. The chlorine may be replaced almost entirely by the fluorine. It is found in large or small hexagonal prisms, usually … Read more

Nitrates and Nitrogenous Compounds

Chemical nitrogen and the “nitrates” of commercial significance are derived mainly from three basic sources: (1) the natural deposits in the form of nitrate-bearing earth and clay, which, being largely water-soluble, can exist only in the most arid portions of the earth; (2) coal, which yields not only nitrogen but also the additional by-product hydrogen … Read more

Morenci Reduction Works – Milling Practices

The Morenci concentrator of the Phelps Dodge Corporation is a part of the project that was completed after five years had been spent in development of the open-pit mine, equipment and process testing in the former No. 6 concentrator, and construction of the reduction works. The reduction works, of which the concentrator is a part, … Read more


Monazite formerly was described as moribund, but, in the light of recent developments, it is no longer so. It is the common source of the rare earths and thorium, both of which are becoming progressively important in industrial and other applications. Moreover, by the action of foreign governments, the sources on which the United States … Read more

Mineral Fillers

Powdered nonmetallic minerals and rocks of many different types are used extensively in industry for incorporation in compositions and manufactured products The term “mineral filler” is commonly employed to designate a material that is used for a specific purpose but not as an essential or reactive component Such a definition is not without objections, and … Read more

Mining in Rhodesia

The Roan Antelope concentrator was originally designed with a nominal milling capacity of 6000 tons of copper ore per day but this was subsequently considerably exceeded. In broad outline the plant consisted of two No. 30 McCully gyratory crushers for coarse crushing, five 5½-ft Standard Symons crushers in open circuit for secondary crushing, ten No. … Read more