Chapter Xiii. Miscellaneous Non-Metallic Minerals 267

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