Pegmatite: Igneous Rock - Pictures, Definition & More
Pegmatite: Pegmatite is an igneous rock composed almost entirely of crystals that are over one centimeter in diameter. The specimen shown here is about two inches (five centimeters) across. Topaz on albite: A crystal of imperial topaz on an albite matrix from a pocket in the Katlang Pegmatite of Pakistan. Specimen is about 4.5 x 3.5 x 3.5 centimeters.