黑雲母, also known as biotite, is a common phyllosilicate mineral within the mica group. It is characterized by its dark color, typically black or brown, and its perfect cleavage, allowing it to be easily split into thin sheets. This mineral is primarily composed of potassium, magnesium, iron, and aluminum silicate. Found in igneous and metamorphic rocks, 黑雲母 plays a significant role in geology. It is often used as an indicator of the conditions under which rocks formed. Additionally, its unique properties make it valuable in various industrial applications, including electronics and cosmetics.