Serpentinite is a deep metamorphic rock consisting mainly of serpentine minerals. The main minerals are serpentine, chrysotile, and antigorite, and the secondary minerals are magnetite, chromite, ilmenite and magnesium-iron carbonate minerals. It is usually light or dark green. Serpentinite is dense and always has a flaky texture with a snakeskin-like pattern. It mainly forms by the hydrothermal metasomatism of ultramafic rocks, which causes serpentinization of the olivine and pyroxene. The serpentinized rocks always form with metallic minerals, including chromium, iron and nickel, and other non-metallic minerals, such as magnesite, talc and asbestos. Serpentine jade transformed from serpentinite is a popular ornamental stone.