EditorialPegmatite. Igneous rock, formed underground, with interlocking crystals usually larger than 2.5 cm in size. Most pegmatites are found in sheets of rock near large masses of igneous rocks called batholiths. From Germany. Natural History Museum, Berlin, ...
EditorialPegmatite. Igneous rock with a grain size around 20 mm. Rocks with this grain size are said to have pegmatitic texture. Piece from Germany. Museum fur Naturkunde. Berlin. Germany. Europe.