EVALUATION OF DEPOSITS DURING PROSPECTING AND EXPLORATORY WORK.

By A.A.Beus.Edited by Lincoln R. Page '31. San Francisco: W. H. Freeman, 1962. 161 pp.$7.50.

During the past year two important studies by Russian geologists have been published as English translations. The comprehensive treatise on Geotectonics by Belusov and the work on Beryllium by Beus do not have English counterparts and therefore will have special value to Western earth-scientists.

The volume on Beryllium by Dr. A. A. Beus, Member of the Academy of Science, Moscow, was edited by Lincoln R. Page '31, whose work for the United States Geological Survey and the Atomic Energy Commission has given him broad experience on beryllium deposits.

The first part of the book contains a scientifically oriented discussion on the occurrence, mineralogy, geochemistry and types of beryllium deposits. The chapter on geochemistry is an important contribution to the subject. The material on types of beryllium deposits indicates that Dr. Beus has read widely in non-Russian geological journals. One of the publications cited repeatedly is the Internal Structure of GraniticPegmatites, of which Dr. Page is one of the co-authors.

The second part of the book contains practical aspects of prospecting, evaluation and methods of exploration of beryllium deposits. In this, the author stresses the importance of careful field study and detailed mapping of beryllium prospects during all stages of their exploration.

The stated aim of the work is to summarize Russian and non-Russian experience concerning the origin and structures of beryllium deposits and to establish the most efficient methods of their prospecting and evaluation. This aim the author has achieved to a high degree. Because the editor has not changed the author's interpretations, the translation reflects accurately Russian opinions on the complex subject of the genesis of beryllium minerals.