Black Tourmaline

Clarity and weight are the two decisive factors affecting the price of black Tourmaline. At about 2.5 cm across, the price of a higher quality stone is usually $2-$8/piece.

The fair toughness of black Tourmaline arises from its indistinct cleavage and internal structure, which can result in potential breakage or chipping when exposed to sharp blows or pressure.

Black Tourmaline maintains its integrity under most everyday conditions, withstanding water, sunlight, and dryness well. It cleans easily but should avoid extreme heat and harsh chemicals.

The tourmaline mineral group is chemically one of the most complicated groups of silicate minerals. Its composition varies widely because of isomorphous replacement (solid solution), and its general formula can be written as XY3Z6(T6O18)(BO3)3V3W, where: X = Ca, Na, K, ▢ = vacancy Y = Li, Mg, Fe, Mn, Zn, Al, Cr, V, Fe, Ti, vacancy Z = Mg, Al, Fe, Cr, V T = Si, Al, B B = B, vacancy V = OH, O W = OH, F, O *Named ferridravite in 1979; renamed to povondraite by the IMA in 1990 Names in existence before the IMA commission existed are in parentheses(). Luinaite-(OH) is a monoclinic distorted variant. A revised nomenclature for the tourmaline group was published in 2011.

Black Tourmaline contains small amounts of tin oxide, which can be extracted; thus it is seen as a commercial source of tin. It is also classified as a semi-precious stone, which means that it is in demand for cutting and polishing for use in jewelry and decorations.

According to folklore, black Tourmaline is said to enhance artistic creativity and build self-confidence. Native American and African tribes, as well as some Australian aboriginal groups, used the stone to protect themselves against danger.

Brightly colored Ceylonese gem tourmalines were brought to Europe in great quantities by the Dutch East India Company to satisfy a demand for curiosities and gems. Tourmaline was sometimes called the "Ceylonese Sri Lankan Magnet" because it could attract and then repel hot ashes due to its pyroelectric properties. Tourmalines were used by chemists in the 19th century to polarize light by shining rays onto a cut and polished surface of the gem.

Tourmaline is found in granite and granite pegmatites and in metamorphic rocks such as schist and marble. Schorl and lithium-rich tourmalines are usually found in granite and granite pegmatite. Magnesium-rich tourmalines, dravites, are generally restricted to schists and marble. Tourmaline is a durable mineral and can be found in minor amounts as grains in sandstone and conglomerate, and is part of the ZTR index for highly weathered sediments.

According to the Madras Tamil Lexicon the name comes from the word "thoramalli" (තෝරමල්ලි) or "tōra- molli", which is applied to a group of gemstones found in the southern parts of the Indian Subcontinent. According to the same source, the Tamil "tuvara-malli" (துவரைமல்லி) and "toramalli" are also derived from the Sinhalese root word. This etymology is also given in other standard dictionaries including the Oxford English Dictionary.

The most protective of all crystals, black Tourmaline supports the base chakra. It is said to encourage balance and neutrality, release stress, and discharge tension. It also known to dispel anxious feelings and negative emotions, creating a relaxed environment. This stone can apparently be used in homes as a protection grid.