Allanite is a mineral that belongs to the epidote group, primarily composed of calcium, iron, and aluminum. It typically appears as dark brown or black crystals and is often found in metamorphic rocks. Allanite can also contain rare earth elements, making it of interest in geology and mineralogy. This mineral is named after the Scottish geologist Thomas Allan, who first described it in the 19th century. Allanite is commonly associated with other minerals such as epidote and hornblende, and it can be used to study the geological history of the areas where it is found.