1911
CONTENTS
| CHAPTER | PAGE | |
| I | Introductory | [1] |
| II | The Origin of Precious Stones | [7] |
| III | Physical Properties—(A) Crystalline Structure | [13] |
| IV | " " (B) Cleavage | [19] |
| V | " " (C) Light | [26] |
| VI | " " (D) Colour | [32] |
| VII | " " (E) Hardness | [39] |
| VIII | " " (F) Specific Gravity | [45] |
| IX | " " (G) Heat | [52] |
| X | " " (H) Magnetic and Electric Influences | [57] |
| XI | The Cutting of Precious Stones | [62] |
| XII | Imitations, and Some of the Tests of Precious Stones | [70] |
| XIII | Various Precious Stones | [80] |
| XIV | " " " (continued) | [88] |
| XV | " " " " | [98] |
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.