Manual Of Determinative Mineralogy

MANUAL OF DETERMINATIVE MINERALOGY WITH AN INTRODUCTION ON BLOWPIPE ANALYSIS. GEORGE J. BRUSH, Late Director of the Sheffield Scientific School of Yale University, REVISED AND ENLARGED, WITH ENTIRELY NEW TABLES FOR THE IDENTIFICATION OF MINERALS, THE LATE SAMUEL L. PENFIELD SIXTEENTH EDITION NEW YORK JOHN WILEY SONS, INC. LONDON CHAPMAN HALL, LIMITEV COPYRIGHT, 1898, BT SAMUEL L. PENFIELD. COPYRIGHT RENEWED, 1926, BY GRACE C. PENFIELD PRINTED IN U. S. A. PREFACE. THE present work is a complete revision of the Manual of Determinative Mineralogy and Blowpipe Analysis 1 by Prof. Geo. J. Brush, which has been very generally used since its iirst appear ance in 1874, as shown by the fact that fourteen editions of it have appeared. In 1896 a revision of the introductory chapters devoted to blowpipe analysis and the chemical reactions of the elements was published, and there are now added a chapter on the physical properties of minerals, devoted chiefly to crystallography, and a new set of analytical tables for the identification of minerals. In preparing the introductory chapters, great pains has been taken in the selection of the tests for the elements. Many of the experiments are performed by means of the blowpipe, but chem ical tests in the wet way are recommended when it is believed that they are more decisive. All the tests have been carefully verified, and many of them have been devised especially for the present work. To make the book more convenient for reference, conspic uous headlines and catch-words have been freely used. The tests for the rare elements, and those for the common ones which are only occasionally employed, are printed in small type. It is hoped that the plan adoptedof giving full directions concerning the methods of manipulation and the quantities of materials to be taken in making many of the tests will be found useful. Ic must be borne in mind constantly that accuracy is of the utmost importance in determinative mineralogy, and it is believed that no methods are so generally to be relied upon for giving deci sive results as those based upon the identification of the chemical constituents of the minerals. Moreover, most minerals can be iden tified by means of very simple tests, although some cannot be determined beyond question without resorting to the more elab iii IV PREFACE. orate methods of quantitative chemical analysis, or an exact deter mination of their crystalline form. The chapter on the physical properties of minerals is a new feature of the book which it is believed will add to its usefulness. The endeavor has been made to present the important subject of crystallography as simply as possible. Importance has been attached to the description of those forms which are most frequent in their occurrence, and, with few exceptions, the examples chosen to illustrate the different systems represent the development of the simple forms which prevail on specimens of common minerals. Rare and complex forms have been treated very briefly, and theo retical considerations have been left largely to the more elaborate treatises on crystallography. In describing the physical properties of crystals the idea has constantly been kept in mind that the book is to be used for the identification of minerals, and, consequently, only those methods are included which are especially important as a means for identification. Optical methods have been omitted becausethey would increa. se the size of the volume to too great an extent, and, excejit as they are accompanied by accurate descrip tions of the crystal forms, their application is limited. The analytical tables for the identification of minerals are an outgrowth of the tables of von Kobell as modified by Professor Brush. The introduction, however, of a large number of new species since 1874 has necessitated a complete rearrangement of the minerals...