Boodt, A. B. de, 132, 213 Borgis, Hortensio, 161 Borneo stones, 154, 170 Bort, _v._ Boart, 103, 129, 133 Bottle-stone, 284 Boule, 118 Bowenite, 263 Braganza diamond, 170 Brazil stones, 138, 165, 166, 169, 194 _et seq._, 201, 215, 223, 236, 243, 244, 248, 266, 269, 270, 274 Brazilian emerald, 111, 220, 221 peridot, 221 sapphire, 111, 221 topaz, 111, 197 Brilliant form of cutting, 92 Brilliant, Scientific, 122 Bristol diamonds, 243 Bruting, 100 Burma stones, 178, 205, 223, 227, 263 Button-pearl, 295 Byes, Bywaters, 136, 150 Cabochon form of cutting, 88 Cacholong, 251 Cairngorm, 239 Callaica, callaina, callais, 258 Calcite, 40, 289 California stones, 156, 195, 202, 224, 259, 265, 267, 275 Californite, 264, 275 Cape-ruby, 213 Carat weight, 72, 84 Carbon, 129 Carbonado, 129 Carborundum, 105 Carbuncle, 89, 215 Carnelian, 247 Cascalho, 139 Cassiterite, 281 Cat’s-eye (chrysoberyl), 38, 90, 233 (quartz), 39, 90, 240 (tourmaline), 39, 219 Hungarian, 244 Ceylon stones, 181, 195, 201, 205, 212, 215, 216, 223, 232, 236, 237, 243, 244, 255, 267, 274, 279, 284 Ceylonese peridot (tourmaline), 221 Ceylonite, 204 Chalcedony, 246 Chatoyancy, 38 Chert, 247 Chessylite, 287 Chrysoberyl, 233 Chrysocolla, 288 Chrysolite (chrysoberyl), 233 (peridot), 225 Chrysoprase, 247 Church, Sir Arthur, 61, 211, 231 Cinnamon-stone, 211 Citrine, 239 Cleavage, 80, 100, 149 Close goods, 149 Colenso diamond, 131 Colour, 53 Colour dispersion, 20, 97 Conchiolin, 293 Coral, 298 Cordierite, 266 Cornish diamonds, 243 Corundum, 172 Crocidolite, 39, 240 Crookes, Sir William, 132, 153 Cross facet, 93 Crystal, 6, 7, 8 Rock-, 97 Cubic system, 8 Culet facet, 93 Cullinan diamond, 94, 100, 168 Culture pearls, 297 Cumberland diamond, 164 Cyanite (Kyanite), 79, 273 Cymophane, 234 Darya-i-nor diamond, 162 De Beers diamonds, 167 Demantoid, 216 Density, 63 Deviation, Minimum, 30 Diamond, Characters of, 128 cutting, 90 gauges, 86 Glaziers’, 135 mining, 146 Occurrence of, in— Borneo, 154 Brazil, 139 German South-West Africa, 155 India, 138 New South Wales, 154 Rhodesia, 155 South Africa, 139 Origin of, 151 -point, 91 -rose, 92 -table, 91 Diamonds, Classification of, 136, 149 Historical, 157 Prices of, 135 Dichroism, 55