  | CHAP. | | PAGE | | I. | Introduction | 1 | | | PART I—SECTION A
THE CHARACTERS OF GEM-STONES | | II. | Crystalline Form | 6 | | III. | Reflection, Refraction, and Dispersion | 14 | | IV. | Measurement of Refractive Indices | 21 | | V. | Lustre and Sheen | 37 | | VI. | Double Refraction | 40 | | VII. | Absorption Effects: Colour, Dichroism, Etc. | 53 | | VIII. | Specific Gravity | 63 | | IX. | Hardness and Cleavability | 78 | | X. | Electrical Characters | 82 | | | PART I—SECTION B
THE TECHNOLOGY OF GEM-STONES | | XI. | Unit of Weight | 84 | | XII. | Fashioning of Gem-Stones | 88 | | XIII. | Nomenclature of Precious Stones | 109 | | XIV. | Manufactured Stones | 113 | | XV. | Imitation Stones | 124 | | | PART II—SECTION A
PRECIOUS STONES | | XVI. | Diamond | 128 | | XVII. | Occurrence of Diamond | 137 | | XVIII. | Historical Diamonds | 157 | | XIX. | Corundum (Sapphire, Ruby) | 172 | | XX. | Beryl (Emerald, Aquamarine, Morganite) | 184 | | | PART II—SECTION B
SEMI-PRECIOUS STONES | | XXI. | Topaz | 197 | | XXII. | Spinel (Balas-Ruby, Rubicelle) | 203 | | XXIII. | Garnet | 207 | | (a) Hessonite (Grossular, Cinnamon-Stone, Hyacinth, Jacinth) | 211 | | (b) Pyrope (‘Cape-Ruby’) | 212 | | (c) Rhodolite | 214 | | (d) Almandine (Carbuncle) | 214 | | (e) Spessartite | 216 | | (f) Andradite (Demantoid, Topazolite, ‘Olivine’) | 216 | | |   |
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