ultramafias
An ultramafia is a rare type of igneous rock that is primarily composed of the mineral olivine, often exceeding 90% of its volume. The term "mafic" refers to rocks rich in magnesium and iron, and "ultra" signifies an even higher proportion of these elements. Peridotite is the most common ultramafic rock, and its varieties include dunite and lherzolite.
These rocks typically form deep within the Earth's mantle, where temperatures and pressures are extremely high.
Ultramafic rocks are generally dense and dark-colored. While not as common at the Earth's surface as more