Tourmaline is one of the most chemically complicated of all Silicate minerals. It is a complex Silicate of Aluminum and Boron and the composition varies widely with Sodium, Calcium, Iron, Magnesium, Lithium and many other elements that enter into it’s structure. It can occur in a long, slender needle-like crystal to a thick prismatic and columnar crystal to a radial like daisy formation. It comes in many colors usually black and brown (iron rich); brown and yellow (magnesium rich); and blue, red, green, yellow, and pink (lithium rich). This mineral is found in igneous rocks, like Granite Pegmatite, and metamorphic rocks such as Schist and Marble.