A very dense rock composed of red-brown garnet and the grape-green pyroxene omphacite. Eclogites possess basaltic bulk chemistry, and their garnets are rich in the components pyrope (Mg₃Al₂Si₃O₁₂), almandine (Fe₃Al₂Si₃O₁₂), and grossular (Ca₃Al₂Si₃O₁₂), while the pyroxenes are rich in jadeite (NaAlSi₂O₆) and diopside (CaMgSi₂O₆). Accessory phases depend on the environment of crystallization, but may include quartz, kyanite, amphibole, olivine, orthopyroxene, zoisite, mica, and rutile, but never plagioclase.