Sodalite: meaning, properties and lore

The mineral

Sodalite is typically a semitransparent to opaque blue stone with calcite veining that resembles lapis lazuli, and it is typically blue or colourless. Sodalite is a complex tectosilicate that falls into the feldspathoid mineral group, with the formula Na8(Al6Si6O24)Cl2. It is durable and easy to cut.¹²⁸⁴

Sodalite typically ranks 5.5-6 on the Mohs hardness scale, which places it softer than quartz (7-7.5) and topaz (8), but harder than fluorite (4) and calcite (3). Its specific gravity runs from 2.14 to 2.40, and massive blue material is about 2.28. Gem Society adds that sodalite may release a hydrogen sulfide smell when cut, due to traces of water and sulfur.⁴⁵¹²

Hackmanite is a variety of sodalite and is the sulfur-bearing form that shows tenebrescence. Hackmanite has the chemical formula Na8Al6Si6O24(Cl2,S). When kept in darkness, hackmanite samples can fade to pale purple and even gray or translucent to opaque white. After exposure to sunlight or artificial light with a UV component, they can quickly develop a much stronger colour.³²⁴⁵

EDXRF spectroscopy found traces of sulfur in all tested samples of sodalite and hackmanite from Myanmar and Afghanistan. Samples from the two countries varied in colour, transparency, UV fluorescence, tenebrescence and UV-Vis-NIR spectra. Burmese material is generally more included than Afghan material and shows weaker fluorescence and phosphorescence. In recent years, gem-quality material has been produced in significant amounts from the Mogok region of Myanmar.⁹

Gem-quality orange sodalite is uncommon, and its colour may be related to the presence of sulfide ions. An absorption band near 480 nm in one examined stone is likely caused by heavy radioactive elements creating an unstable colour center substituting for Cl– in a tetrahedron of Na+ ions. Raman peaks at 263, 294, 464, 969, 986, and 1058 cm–1 are characteristic features of sodalite.¹

Sodalite from the Tajonngnadine mine at Mogok is composed with nepheline and shows a beautiful purple or deep lilac colour. Burma sodalite contains no sulphur according to qualitative tests, and the Mogok crystals have a refractive index of 1.479 for sodium light. The purple colour disappears and the material becomes white when warmed, even very slightly, and it fades somewhat on long exposure to light without being entirely bleached.⁷

History and lore

Giesecké observed in 1806 that a freshly broken surface of sodalite from Kangdluarsuk, Greenland, had a peach-blossom-red colour that immediately disappeared on exposure. Vredenburg described in 1904 a sodalite from Kishengahr state in Rajputana that turns pink in the dark and loses the colour in light. Robert Allan noted in his Manual of Mineralogy (1834) that Thomas Allan had observed the same pink colour in Greenland sodalite.⁷

Walker and Parsons drew attention to a sodalite near Bancroft, Ontario, with a fine pink colour that disappears in ten to thirty seconds in direct sunshine. Annerstein and Hassib wrote on blue sodalite and its colour in the Canadian Mineralogist in 1979. published work on colour centres in sodalite in the American Mineralogist in 1985.⁷¹

Europeans later discovered sodalite in Greenland in 1811, according to Cosmopolitan. Sodalite became widely used in jewellery and decor after large deposits were found in Canada in 1891. The stone is sometimes called Princess Blue because the Canadian deposits were discovered during a visit from members of the British royal family.⁴

Fire Mountain Gems reports that sodalite was used from around 2,600 B.C., when the Caral peoples in modern-day Peru and the Tiwanaku peoples in modern-day Bolivia both traded for it. Caldera Gem says that the ancient Egyptians, Greeks and Mayans also used sodalite. The index of The Curious Lore of Precious Stones lists sodalite as the gem of Canada on page 363.⁴¹⁰

Birthstone, zodiac and chakra links

Crystal practitioners say sodalite has no monthly birthstone tie. Linking it to the throat chakra is a modern practice-based idea, not something drawn from an old list. Among zodiac associations, practitioners most often name Sagittarius, followed by Virgo, though opinions differ and these pairings are also modern.¹¹¹²

What crystal practitioners say

Crystal practitioners use sodalite mainly for the mind, and it is traditionally associated with intellectualism and communication. Practitioners believe it can improve clarity, self-expression, intuition, insight, wisdom, emotional stability and calm, and that it enhances the ability to analyze complex problems and promotes rational and logical thinking. Said to quiet the mind, it is also credited with providing a sense of inner peace.⁴¹¹

Believers say sodalite stimulates creativity and inspires originality, and crystal users frequently recommend it for artists, writers and other creatives. Crystal pros often recommend placing sodalite around the workspace, where it is said to boost intellectual energy, creativity and focus.¹¹⁴

Practitioners say sodalite may be worn, carried in a pocket or placed around a home or workplace, and held in the palm during meditation. Practitioners advise placing a tumbled sodalite stone on the eyelids and taking gem water, or wearing it as a necklace or pendant around the neck. The book's authors hold that sodalite is a very good crystal for fluid regulation in connection with the eyes.⁴¹³

According to The Healing Crystals First Aid Book, sodalite is believed to help with long-term hoarseness when something unspoken gets stuck in the throat. The book's authors also say sodalite is believed to raise awareness of the moment when something must be said immediately and to remove blockages in speaking out. Sodalite is said to aid awareness around eating and to reduce the need for other forms of expansion. For throat complaints, the book advises wearing sodalite as a necklace or pendant on the throat, or taking gem essence or gem water.¹³

The International Gem Society recommends cleaning sodalite with warm water, mild detergent and a soft brush.¹¹⁴

What testing has found

In his review of 150 complementary and alternative treatments, Edzard Ernst found no rigorous trials that test whether crystal healing has therapeutic value. Ernst also held that no scientific evidence shows any benefit from crystal healing beyond the placebo effect. He attributed the pleasant feelings reported after crystal healing to a strong placebo response and to cognitive bias among its believers.¹⁴

A 2001 study by Christopher French challenged 80 volunteers to tell real crystals from fake ones after holding them and meditating. The French team concluded that crystals did not help people, and that the power of suggestion did.¹⁴¹⁵

Ted Kaptchuk, a Harvard Medical School professor, argues placebo effects should not be discarded because they may be dramatic in unconventional medicine. Some researchers say crystals likely do not directly act on the body, but may have indirect benefits explained by the placebo effect.¹⁵