Marble. See [p. 465.]
Mica-schist, or Micaceous-schist. A slaty rock, composed of mica and quartz in variable proportions. See [p. 465.]
Mica-slate. See Mica-schist, [p. 465.]
Phyllade. D'Aubuisson's term for clay-slate, from φυλλας, a heap of leaves.
Primary Limestone. See Hypogene Limestone, [p. 465.]
Protogine. See Talcose-gneiss, [p. 464.]; when unstratified it is Talcose-granite.
Quartz Rock, or [Quartzite]. A stratified rock; an aggregate of grains of quartz. See [p. 465.]
Serpentine occurs in both divisions of the hypogene series, as a stratified or unstratified rock; contains much magnesia; is chiefly composed of the mineral called serpentine, mixed with diallage, talc, and steatite. The pure varieties of this rock, called noble serpentine, consist of a hydrated silicate of magnesia, generally of a greenish colour: this base is commonly mixed with oxide of iron.
Talcose-gneiss. Same composition as talcose-granite or protogine, but either stratified or laminated. See [p. 464.]
Talcose-schist consists chiefly of talc, or of talc and quartz, or of talc and felspar, and has a texture something like that of clay-slate.