Eclogite is a high pressure and high temperature regional metamorphic rock that usually formed from a basaltic rock that is believed to have subducted and become subject to extreme conditions. It has red and green colors, and a high density. Eclogite consists of the high pressure species of the mineral garnet which is pyrope, it also has the pyroxene jadeite which is also formed at high pressures. Small amounts of kyanite, hornblende, and zoisite can also be included in the composition of eclogites. It is believed that part of the upper mantle is composed of eclogites because the pressures and temperatures in the mantle are in the stability range of the minerals that compose eclogites.