Biotite is a mineral that can be found ubiquitously across the world, according to MinDat.org. It has been recovered from every continent on Earth with the exception of Antarctica.
According to Webmineral.com, biotite is not a single type of rock, but the name instead refers to a specific grouping of minerals that include phlogopite, siderophyllite and eastonite. Biotite itself is a type of mica, and it is also known internationally under the following names: iron mica, lepidomelane, manganophyllite, micaceous iron ore and oxybiotite. Webmineral.com also states that biotite contains atoms of potassium, magnesium, aluminum, iron, silicon, hydrogen, oxygen and fluorine.