NATURAL ABRASIVES 267
Economic features 267
Geologic features 269
ASBESTOS 270
Economic features 270
Geologic features 271
BARITE (BARYTES) 272
Economic features 272
Geologic features 273
BORAX 274
Economic features 274
Geologic features 275
BROMINE 277
Economic features 277
Geologic features 278
FULLER'S EARTH 278
Economic features 278
Geologic features 279
GRAPHITE (PLUMBAGO) 279
Economic features 279
Geologic features 282
GYPSUM 283
Economic features 283
Geologic features 284
MICA 285
Economic features 285
Geologic features 287
MONAZITE (THORIUM AND CERIUM ORES) 288
Economic features 288
Geologic features 289
PRECIOUS STONES 289
Economic features 289
Geologic features 291
SALT 294
Economic features 294
Geologic features 295
TALC AND SOAPSTONE 299
Economic features 299
Geologic features 299