Domite. An earthy trachyte, found in the Puy de Dome, in Auvergne.
Euphotide. A mixture of grains of Labrador-felspar and diallage. (Rose, ibid. p. 19.) According to some, this rock is defined to be a mixture of augite or hornblende, and saussurite, a mineral allied to jade. (Allan's Mineralogy, p. 158.) See [Diallage rock].
Felspar-porphyry. Syn. Hornstone-porphyry; a base of felspar, with crystals of felspar, and crystals and grains of quartz. See also [Hornstone].
Gabbro, see [Diallage rock].
[Greenstone]. Syn. Dolerite and diorite; components, hornblende and felspar, or augite and felspar in grains. See above, [p. 372.]
Greystone. (Graustein of Werner.) Lead grey and greenish rock, composed of felspar and augite, the felspar being more than seventy-five per cent. (Scrope, Journ. of Sci. No. 42. p. 221.) Greystone lavas are intermediate in composition between basaltic and trachytic lavas.
[Hornblende Rock]. A greenstone, composed principally of granular hornblende, or augite. (Leonhard, Mineralreich, &c., p. 85.)
[Hornstone], Hornstone-porphyry. A kind of felspar porphyry (Leonhard, ibid.), with a base of hornstone, a mineral approaching near to flint, differing from compact felspar in being infusible.
Hypersthene Rock, a mixture of grains of Labrador-felspar and hypersthene (Rose, Ann. des Mines, tom. 8. p. 13.), having the structure of syenite or granite; abundant among the traps of Skye. Some geologists consider it a greenstone, in which hypersthene replaces hornblende.
Laterite. A red jaspery rock, composed of silicate of alumina and oxide of iron. Abundant in the Deccan, in India; and referred to the trap formation; from Later, a brick or tile.