DICTIONARY of GEMS and GEMOLOGY V: ;8Y the SAME PUBLISHERS

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DICTIONARY of GEMS and GEMOLOGY V: ;8Y the SAME PUBLISHERS DICTIONARY OF GEMS AND GEMOLOGY V: ;8y THE SAME PUBLISHERS THE STORY OF DIAMONDS (3rd Edition 1946) By Austin, Mercer and Shipley FAMOUS DIAMONDS OF THE WORLD (5th Edition 1948) By Robert M. Shipley JEWELERS* POCKET REFERENCE BOOK (1947) By Robert M. Shipley HANDBOOK OF GEM IDENTIFICATION (2nd Edition, 1948) By Richard T. Liddicoat, Jr. DICTIONARY OF DIAMONDS (In preparation) A ROMAN BOOK ON PRECIOUS STONES (In preparation) By Dr. Sydney H. Ball PROPERTIES OF GEM VARIETIES OF MINERALS (posthumously 1948) Dr. Edward Wigglesworth Past President, G.I.A. INTRODUCTORY GEMOLOGY (1945) By Webster and Hinton GEMS AND GEMOLOGY, a quarterly. Course* FUNDAMENTALS OF GEMOLOGY, including the factors af- fecting the value of gems. GEMS, their substitutes and the technique of testing and grading them. ADVANCED DIAMONDS ADVANCED GEMOLOGY A SHORT COURSE IN DIAMONDS DICTIONARY OF GEMS AND GEMOLOGY including Ornamental, Decorative and Curio Stones A glossary of over 4000 English and foreign words, terms and abbreviations which may be encountered in English literature or in the gem, jewelry or art trades. BY ROBERT M. SHIPLEY Founder* Gemologicat Institute of America and American Gem Society ASSISTED BY ANNA McCONNELL BECKLEY Research Librarian, Gemological Institute of America EDWARD WIGGLESWORTH, PH.D., C.G. Past President, Getnoloffical Institute of America ROBERT M. SHIPLEY, JR. Formerly Director of Laboratories, Gemotogical Institute of America Vol. 4 of The Jeweler's Library Fourth Edition First Printing, GEMOLOGICAL INSTITUTE OF AMERICA 541 South Alexandria, Los Angeles 5 1948 COPYRIGHT, 1948, BY THE *GEMt)i*OGicAL INSTITUTE OF AMERICA, INC. All rights reserved. This book, or parts thereof, may not be re- produced in any form without permission of the publishers. PRINTED IN THE UNITED STATES OF AMERICA PREFACE TO FOURTH EDITION To keep this Dictionary completely current and of the greatest possible help and value to its user, new develop- ments and discoveries in the gemological field, since publi- cation of the third edition in 1947, have been added. Cross references are used when it is believed such procedure will give lucidity to the true meaning of defini- tions. In such instances the references are indicated by bold face type in the copy. Much of the value of this book will be lost unless in- structions outlined in "How to Use This Book," page IX, are read and followed most carefully. Key to pronuncia- tion is given and certain departures from conventional dictionary practices are explained. Robert M. Shipley September 1, 1948 PREFACE TO THE THIRD EDITION Additional changes and corrections have been made to previous editions. Most of these were the result of addi- tional research of the writer as he compiled the glossary of the Jewelers Pocket Reference Book from February 1946 to April 1947. Further corrections were made as the result of sug- gestions or criticisms of readers and of Dr. E. Giibelin, as well as R. T. Liddicoat, Jr., and Dr. George Switzer of the Institute's staff. Robert M. Shipley May 28, 1947 PREFACE TO THE SECOND EDITION Toward fulfillment of our purpose of meriting the ac- ceptance of this Dictionary as an international reference book for the gemological profession, criticism of the first edition was invited from the several outstanding gemolo- gists, mineralogists and practical jewelers mentioned later in the preface. As a result, errors of varying importance have been corrected, definitions have been clarified in the body of the Dictionary, while valuable additions to many of the definitions will be found in the Addenda. Cross references in definitions in the Dictionary call to the reader's attention the entries among the addenda, as in the definition of bezel, on page 24, which contains a ref- erence to page 255, on which appear additional definitions of bezel. Because of mechanical difficulties, no attempt has been made in this edition to include a number of additional words and their meanings which have been suggested. However, many new alternate definitions have been added ; the book has been carefully checked for typographical errors or am- biguous phrasing ; and the few factual errors of the first edition have been eliminated. Credit for revisions is due principally to the generous cooperation of the following internationally recognized au- thorities on gemstones : Dr. B. W. Anderson, Director of the Precious Stone Laboratory, London Chamber of Com- merce ; Dr. Sydney H, Ball, author of especially important reports and articles on diamonds and other gemstones; Dr. Edward Giibelin, Certified Gemologist, internationally edacated gemologist and founder of the Swiss Gemmologi- cal Association ; Dr. Edward H. Kraus, co-author of Min- eralogy, and Gems and Gem Materials; G. F. Herbert Smith, author of Gemstones, and president of the Gemmo- logical Association of Great Britain; L. J. Spencer, translator of Bauer's Precious Stones, author of Precious Stones, and secretary of the Mineralogical Society of Great Britain ; and A. Espositer, lapidary of New York. George H. Marcher, Certified Gemologist, lapidist and authority on gemstones of western United States, contributed invaluable criticisms and suggestions. To these men we are especially grateful for their generous assistance toward what we hope will be only the first of many improved editions of the Dictionary in future decades. For the Authors, Robert M. Shipley. December 14, 1945 VI INTRODUCTION The forerunner. The forerunner of this dictionary was a gem- ological glossary published serially from January, 1934 to December, 1940, in Gems & Gemolagy, the quarterly periodical of the Gemological Institute of America, and later published in booklet form for use exclusively with its mail courses in gemology. That glossary was com- piled by various members of the Staff of the Institute during the years of its serial publication. It contained about 1,700 definitions and pronunciations. The sources. The definitions in this rewritten and expanded work, have been written by the compiler; or he or his assistant, A. M. Beckley, has condensed them from or checked them against the important books, reports, or articles which have been written by recognized gemo- logical authorities in English, German, or French. The name of any such gemological authority has been men- tioned in the definition only in the event (1) that the authority has written the definition or otherwise furnish- ed the information especially for this dictionary, (2) that the authority has been the only authority to make the statement indicating that it was the result of personal research, or (3) that the authority has differed from the compiler, or with other recognized authorities in which event a digest of the definitions of those author- ities who are in disagreement is also included in the definition. See Chapter entitled THE USE OF THE BOOK for more detailed information on this subject. Special recognition. Especial appreciation is due not only to the assistant compilers, Edward Wigglesworth, Robert VII M. Shipley, Jr. and .A. M. Beckley, all of whom read the proof and supplied invaluable corrections and additions, but also to staff members of G.I. A. who read proof ; to Dr. G. F. Herbert Smith, F.R.A.S., and Messrs. B. W. Anderson, F.G.A., and R. Webster, F.G.A., who gave special permission for the numerous references to their works; and to Dean Edward H. KTraus, and Mr. H. Paul Juergens, G. G., for specialized correction and advice, from the latter on the subject of pearls. Future editions will become increasingly useful if our read- ers will advise the publishers of any seeming errors in the copy; of definitions which may seem to be at vari- ance with definitions or statements of authors or trade authorities of international recognition; or of additional definitions, or other additions which in their opinion will enhance the value of the book. Suggestions should be addressed to: The Gemological Institute of America, 541 South Alexandria, Los Angeles 5, California. The Companion Volume. A diamond glossary, a portion of which appeared serially in the periodical Gems & Gemology, is now in preparation and will later be published as a book uniform with this volume. Hence the only definitions in this dictionary which contain any specialized information concerning diamonds are a few brief definitions of the bet- ter known and most famous diamonds, the replicas of which are frequently exhibited. vm THE USE OF THE BOOK In determining the format of this book the compiler's prin- cipal purpose was to produce a compact, all-inclusive reference book which for the layman or the beginning student would (1) be a pocket-sized volume, (2) con- tain a definition of every unusual word or term used in any of its definitions, and (3) contain all essential gemo- logical information in such form that it will create a demand that it be revised and expanded frequently by the present compiler and his successors in future years. To accomplish this principal purpose certain departures from conventional practice have been made: Titles In quotation marks mean that the name or term is incorrect or misleading, as evidenced by the definition. For example: "African jade" is an incorrect term for green grossularite, as stated in the "African jade" def- inition. Names or terms in bold type, whether in, the body of the definition or at the end of it, mean that the reader should refer to the entry for that name to be sure that the full meaning of the first definition is clear. While the reader may find no information which is new to him under the second definition, even advanced students of gemology are advised to follow this practice to assure accuracy. The physical properties of varieties of gemstones are not included under the definition of the variety unless such properties are especially distinctive from those of the entire gem mineral species under which the properties IX are, of course, listed.
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