A dark igneous porphyry embedded with feldspar crystals.
some of a few dark augitic eruptive rocks allied to basalt.
Any one of several dark-colored augitic, eruptive rocks allied to basalt.
A fine-grained greenish- or brownish-black aggregate of plagioclase, augite, olivin, magnetite, or titaniferous iron and some chloritic mineral, generally delessite.
it really is proposed, on the go classification associated the quantitative system of classification of igneous rocks (see rock), to bring back the definition of melaphyre to its early value and apply it to all dark-colored porphyries, of any structure.