- Black lava rock - Igneous rock - Volcanic rock - 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. - An imitation, in pottery, of natural basalt; a kind of
black porcelain.
- Yellowish gemstone - A mineral, composed of silica, magnesia, and iron, of a
yellow to green color. It is common in certain volcanic rocks; --
called also olivine and peridot. Sometimes used as a gem. The name was
also early used for yellow varieties of tourmaline and topaz.