A black rock, formed when a common type of volcanic lava cools and hardens Basalt is faintly magnetized, in the direction of the magnetic field existing when if first cools
A fine-grained, usually dark-coloured, crystalline igneous rock, with silica content less than 53% by weight
a hard, dense, dark volcanic rock composed chiefly of plagioclase, pyroxene, and olivine and often having a glassy appearance, one of the most abundant forms of igneous rock on earth with more than 90% of all volcanic rock and 90% of basic igneous rock being basalt - BACK>>
The fine-grained member of the gabbro family of igneous rock Its mineral composition gives it a dark or black color
A hard rock of varied mineral content; volcanic in origin, it makes up much of the Earths crust
A fine-grained, mafic volcanic rock consisting mainly of the minerals plagioclase, olivine, and pyroxene
The most common of volcanic (igneous) rocks, it is both dark and fine-grained Augite and olivine are common dark minerals in basalt
A rock of igneous origin, consisting of augite and triclinic feldspar, with grains of magnetic or titanic iron, and also bottle-green particles of olivine frequently disseminated
A fine-grained volcanic rock used for the manufacture of chipped stone artifacts Colour ranges from black to grey; texture granular to glass like