Chlorite schist (also known as green schist) is a metamorphic rock which is believed to form from regional metamorphism, where temperatures and pressures associated with metamorphic rocks are low, (around 300 - 500 °C) and up to a maximum pressure of 10 kilobars. Like other schist, it contains the common schist mineral, muscovite mica. However, the rock gets its green colouration from the high amount of chlorite and serpentine within it, both being green minerals, with serpentine also being a platy mineral like muscovite mica. This gives the overall rock a platy structure, often splitting in slices and slabs along the cleavage planes on the platy minerals. In the case of this particular rock specimen, the main colouration comes from chlorite, and the rock is sometimes referred to as chlorite schist. These specimens come from Auchtertyre in Ross-shire, Scotland and are available in various sizes, supplied in a card tray with an information label.