HQRP-Crystal Black Tourmaline Sphere (NN15) You will receive: ___ (Stand not Included). Tourmaline is not a single mineral, but a group of several closely related minerals. The three most well-known members are Elbaite, Schorl, and Dravite. Other lesser known members include Uvite, Liddicoatite and Buergerite. Tourmaline is a crystalline boron silicate mineral compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium. Tourmaline is classified as a semi-precious stone and the gemstone comes in a wide variety of colors. Chemical Composition: (Na, Li,Ca) (Fe2, Mg, Mn, Al)3 Al6 I(OH)4 I (BO3)3ISi6O18I; Color: Most commonly black, but can range from colorless, brown, violet, yellow, orange, blue, red, green, pink, or bi-colored, or even tri-colored; Mohs scale hardness: 77.5; In its natural state, all the Tourmalines are characterized by parallel ridges (striations) which run the length of the crystal, as are the Black Tourmalines which are the most common in the Tourmaline group. Tourmaline forms in igneous and metamorphic rocks and veins. It frequently occurs with Lepidolite, Microcline, and Spodumene in granite pegmatites and others. (The above information is provided solely for informational purpose. Kindly note that all stones are offered for decorative purposes only. Please, handle your stones with great care, do not grind or crumble them, do not dip or add them into your food or drink, do not use any parts of them in any elixirs, potions, lotions etc. Always make sure you wash your hands before and after working with your crystals.)