THE CHEMISTRY,

PROPERTIES AND TESTS OF

PRECIOUS STONES

BY THE SAME AUTHOR

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THE CHEMISTRY, PROPERTIES

AND TESTS

OF

PRECIOUS STONES.

BY

JOHN MASTIN, M.A. D.Sc. Ph.D. Litt.D.

F.S A.SCOT. F.L.S. F.C.S. F.R.A.S. F.R.M.S. R.B.A.

Author of "Parasites of Insects," "The True Analysis of Milk," "Plate-Culture and Staining of Amœbæ," etc., etc.

London

E. & F. N. SPON, Limited, 57 HAYMARKET

NEW YORK

SPON & CHAMBERLAIN, 123 LIBERTY STREET

1911

CONTENTS

PREFACE

Some little time ago certain London diamond merchants and wholesale dealers in precious stones made the suggestion to me to write a work on this section of mineralogy, as there did not appear to be any giving exactly the information most needed.

Finding there was a call for such a book I have written the present volume in order to meet this want, and I trust that this handbook will prove useful, not only to the expert and to those requiring certain technical information, but also to the general public, whose interest in this entrancing subject may be simply that of pleasure in the purchase, possession, or collection of precious stones, or even in the mere examination of them through the plate-glass of a jeweller's window.

JOHN MASTIN.

Totley Brook,
    near Sheffield.

June 1911.

THE CHEMISTRY, PROPERTIES AND TESTS OF PRECIOUS STONES

CHAPTER I.

INTRODUCTORY.

What constitutes a precious stone is the question which, at the onset, rises in the mind, and this question, simple as it seems, is one by no means easy to answer, since what may be