PAGE
Phenocrystalline quartz - - 141
Phosphorescence ... 34
Pitt diamond - - - - 72
Plasma
153
Pleochroism - - - - 31
Pleonaste .... 96
Polarization - - - - 29
Polarizing apparatus - - 30 Polycrase .... 140
Pomegranate ruby - 97
Prase - - - - - 152
Precious stones defined - - 3
Prehnite - - - - 193
Pseudo-emerald - - - 198
Pyrite.....189
Pyro-electricity
34
Pyrope - - - - - 127
Quartz .... 141
aventurine - 149
cryptocrystalline - - 150
phenocrystalline - - - 141
rose .... 146
rutilated - - - - 148
sagenitic - - - 148 smoky ....
147
Radio-active gems ... 35
Refraction - - - - 26
Regent diamond ... 72
Resin opal ... - 160
Resinous luster
16
Rhinestone - - - 142, 143
Rhodonite - - - - 194
Rock crystal . . . 141
Rose cut -
46
Rose quartz ... - 146
Rubicelle .... 95
Rubellite - - - 111, 116
Ruby .... 89
almandine - - - - 95
artificial production of - - 91
Balas - - - - 95
Cape
129
pomegranate - - - 97
value of - - - - 89
Ruby spinel - - - - 95
Rutile .... 137
Rutilated quartz - - - 148
Sagenite -
148
Sagenitic quartz - - - 148
Sancy diamond ... 74
Sapphire d'eau - - - - 136
Sapphire -
92
of Australia - - - - 93
of Montana
93
!8
