Biotite

Biotite is a common dark-colored mineral found in many types of rocks, especially in igneous and metamorphic rocks. It belongs to the mica group, characterized by its thin, flexible sheets that can peel off easily. Biotite is composed mainly of potassium, magnesium, iron, and lithium. Its color ranges from black to dark brown, and it has a shiny, reflective surface. In geology, biotite helps scientists understand the history and conditions of rock formation. It’s also used in industry for insulation and electrical applications because of its insulating properties.