Calcite is a mineral composed of calcium carbonate, with the chemical formula CaCO₃. It is one of the most common minerals on Earth and is found in a wide variety of geological formations. This mineral is known for its diversity of shapes and colors, ranging from white to yellow, orange, red, green and even colorless.
Calcite crystallizes in the trigonal system and often appears as rhombohedrons, although other crystalline forms such as scalenohedrons are also common. Its hardness is 3 on the Mohs scale, making it relatively soft. One of its most remarkable properties is its double refraction, which splits a beam of light in two across the crystal.
