noun a basic, dark-colored, holocrystalline, igneous rock, consisting essentially of a triclinic feldspar and pyroxene with magnetic iron;
often limited to rocks pretertiary in age. it includes part of what was early called greenstone.
noun a basic, dark-colored, holocrystalline, igneous rock, consisting essentially of a triclinic feldspar and pyroxene with magnetic iron;
often limited to rocks pretertiary in age. it includes part of what was early called greenstone.
Webster English vocab. Английский словарь Webster. 2012