eclogite

Eclogite is a dense, high-pressure metamorphic rock formed deep within the Earth's crust or upper mantle. It results from the transformation of basalt or similar rocks when subjected to extreme pressures and temperatures, typically during tectonic plate collisions. Eclogite is characterized by its dark color and contains minerals like garnet and omphacite (a type of pyroxene). Its formation indicates regions where rocks have been subjected to deep subduction processes, and studying it helps geologists understand Earth's interior dynamics and the movement of tectonic plates.