igneous rocks that are dense and dark-colored thet form from magma that is rich in iron and magnesium and poor in silica

light-colored, silica-rich igneous rock that is less dense than basaltic rock. dense, dark-colored igneous rock formed from magma; rich in magnesium and iron and poor in silica. Describes magma or igneous rock that is rich in feldspars and silica and that is generally light in color.

Light colored silica rich ringeous rock than is less than dense than bacsaltical rock