Black tourmaline: meaning, properties and lore

The mineral

Schorl is best known as black tourmaline, and it is exclusively black, never transparent or even translucent. It is the most common form of tourmaline and a major tourmaline species, typically black because it is rich in iron. Tourmalines share silicon, aluminum and boron, and share the same crystal structure as a group of closely related species, of which schorl is one.¹²

Schorl has the chemical formula NaFe2+3Al6(BO3)3Si6O18(OH)4, and it is a borosilicate mineral with a complex structural formula whose compositional variability creates a supergroup of minerals. Its Mohs hardness is 7–7.5, and tourmaline in general is rated 7 to 7.5 on the Mohs scale. Schorl has a specific gravity of 3.1–3.2.¹³⁴⁵

Schorl crystallises in the hexagonal system and is usually found as elongated, heavily striated prismatic crystals, many with a flattened pyramidal termination. It is strongly pyroelectric and piezoelectric, and tourmaline's electrical pyroelectric property causes it to gain a slight charge when heated under display case lights.¹⁶

Schorl is most often found in granite pegmatites and also in skarns, and it forms in a wide variety of rock types. Outstanding crystals come from the Shigar Valley and Stak Nala in the Skardu District of Pakistan, and schorl is also found in Quadeville, Renfrew Co., Ontario, Canada. Tourmaline is most commonly found in Brazil and is also mined in Afghanistan, Pakistan, Kenya, Madagascar and Mozambique.¹²³

Some dark tourmalines absorb light so intensely that they appear almost black from certain directions.⁷

Schorl is occasionally used in jewelry as a black gemstone, though it is rarely used as a gem. Dark-toned tourmalines are more common in the marketplace and have much lower prices than fine green or brighter bluish green tourmaline.¹²⁷

Heat can damage tourmaline and high heat can alter its colour, while tourmaline is generally stable to light and is not affected by exposure to chemicals. Sudden temperature change can cause it to fracture, and its toughness is considered Fair. Color changes caused by irradiation can fade with exposure to heat or bright light.³⁶⁴

History and lore

The name tourmaline is traced in different accounts.⁸⁹³

Dutch lapidaries called tourmaline Aschentrekker, or Ash-Attractor, after children in Amsterdam were said to have first noticed its attraction of ash and straw. Linnaeus is said to have first derived the action of the Ash-Attractor from electric energy and named tourmaline the Electrical Stone. Dutch jewellers are said to have discovered its electric phenomena by heating stones in the fire to test their hardness.⁹

Lémery reported tourmaline's attraction and repulsion to the French Academy of Sciences in 1717, though he attributed it to magnetic influence. Aepinus showed the electric nature of tourmaline's attraction and repulsion, communicating his conclusions to the Berlin Academy of Sciences in 1756. Benjamin Franklin wrote in a letter of June 7, 1759, to Dr. William Haberden about tourmaline's electric behaviour.⁹

Franklin noted that when he wore a tourmaline mounted in a ring, the natural heat of the finger was enough to charge the stone. Pliny's lychnis may have been tourmaline, which attracted straws or paper when heated by the sun or hand-friction. Theophrastus, in the third century B.C., may have referred to green tourmaline when describing the emerald as produced from jasper.⁹

The first recorded tourmaline was a green crystal discovered in 1554 by a Spanish explorer who thought it was emerald. Hogarth depicted a spendthrift fop distracted by tourmaline's strange phenomena in one of his designs.⁸⁹

Birthstone, zodiac and chakra links

Black tourmaline (schorl) is assigned to the Root Chakra by crystal practitioners, and this chakra link is a modern one.

In modern astrology, crystal practitioners link black tourmaline with Capricorn, a more recent association.

Crystal practitioners assign black tourmaline to the Earth element and give it the numerical vibrations 3 and 4, both modern practitioner links. The stone is assigned as the birthstone of October by crystal practitioners, a modern list.

Tourmaline is listed as an alternate birth-stone for October in the Kansas City list, and tourmaline is given to celebrate the eighth wedding anniversary. The Curious Lore of Precious Stones describes tourmaline as a gem known only in modern times or since the eighteenth century, and its author judges it out of place in the birth-stone list.¹⁰³

The Curious Lore of Precious Stones links tourmaline to the sentiment of accident in a list of gem meanings for precious stones. In the lore of the Chinese mandarins' ranks, red or pink tourmaline was given first rank, with ruby.¹⁰

What crystal practitioners say

Crystal practitioners associate black tourmaline with the mind and with self-assurance. Black tourmaline is believed to instill personal power and confidence.³

Practitioners of spiritual practice regard black tourmaline as a protective stone that shields the body from negative energies and psychic attacks. Black tourmaline is traditionally associated with creating a protective energetic shield for personal boundaries and spaces.

Spiritual practitioners use black tourmaline for protection from negativity and electromagnetic radiation.

Users may charge black tourmaline by placing it under the full moon overnight, in sunlight, buried in the earth, or on a crystal cluster. Gentle energetic cleansing can be done with moonlight, sound or visualisation.

Crystal practitioners say black tourmaline should be periodically cleansed and recharged to perform. Crystal healers say that polishing the stone gives it a mirrored finish that repels bad vibes, ill will and negativity.

Crystal healers say black tourmaline is essential for balancing the Root Chakra and for absorbing surrounding negativity. Crystal practitioners say black tourmaline is assigned as the birthstone of October because it is the month when nights grow darker earlier each day.

What testing has found

Edzard Ernst, who analysed 150 complementary and alternative treatments, found no rigorous trials testing the therapeutic value of crystal healing. In Ernst's view, no scientific proof exists that crystal healing has any positive effect beyond placebo. He attributes the pleasant feelings reported by believers to a strong placebo effect and to cognitive bias.¹¹

In 2001, British psychologist Christopher French tested 80 volunteers who were asked to distinguish genuine crystals from imitations after holding them and meditating. Participants handling fakes and genuine stones gave comparable accounts, which pointed toward a placebo effect.¹¹

Jarry explains that rigorous clinical trials strip interventions of placebo effects to determine whether they have a specific benefit. Jarry says people who feel better after using crystals may testify publicly, creating the illusion that crystals work, without knowing what would have happened without them.¹¹