Are you an October baby? Well, Tourmaline is your birthstone, along with Opal!
It comes in a staggering variety of colours. Because of Tourmalines’ colourful appearance, it has often been confused with other gemstones throughout history.
Tourmaline has an inexplicable sheen to it and looks ethereal and mystical.
Introduction and Colour
Tourmaline is classified as a semi-precious stone and is a crystalline boron silicate mineral compound with many elements.
Tourmaline gemstones come in an eclectic variety of colours. In fact, out of all gemstones, Tourmaline has the widest range of colours, occurring in almost every shade and hue you can think of. Rarely is it colourless.
Black Tourmalines are rich in iron, and so are those that are bluish-black to deep brown in colour. Tourmalines that are rich in magnesium are generally in varieties that are brown to yellow. Tourmalines rich in lithium occur in almost any colour: blue, green, yellow, pink etc.
Formation and chemical composition
The most common cause behind the formation of the Tourmaline stone is hydrothermal activity. These stones begin to form when water and hot vapours carry the minerals needed to form this crystal into pockets, voids and fractures.
Tourmalines share the elements of silicon, aluminum and boron but also contain a complex mixture of other elements such as fluorine, lithium, calcium, magnesium, iron, manganese, chromium, vanadium and copper.
History of Tourmaline
Did you know that when the green Tourmaline was first discovered in the 1500s, it was mistaken to be an emerald for several centuries? In 1554, Spanish conquistador Francisco Spinoza’s expedition found the green Tourmaline in Brazil – named the “Brazilian emerald” – the first recorded green Tourmaline crystal.
It wasn’t until the 1800s when mineralogists identified Tourmaline as a separate mineral species. The name Tourmaline comes from the Sinhalese term “tōramalli”. That was the name Dutch merchants gave to all coloured crystals that were discovered on the island of Sri Lanka.
Tourmaline is mined chiefly in Brazil, several parts of Africa such as Nigeria, Madagascar, Tanzania, Malawi, Mozambique, Namibia and Malawi. Other active mines can be found in Afghanistan, India, Myanmar, Canada, Australia, Pakistan, Russia, Siberia, Thailand and USA.
Tourmaline species and varieties
Among gemologists, four species of Tourmaline are of great importance, namely: Schorl, Elbaite, Liddicoatite and Dravite.
Schorl – It is the most common Tourmaline and may account for 95 percent of all Tourmalines found in nature. Schorl is exclusively black and is not transparent or translucent. It is usually heavily striated and has elongated prismatic crystals.
Elbaite – it is the most well-known and valuable form of Tourmaline. Most multicoloured varieties of Tourmaline are of the Elbaite variety. It is allochromatic and can be pleochroic.
Liddicoatite – This variety of Tourmaline was not recognised as a separate species until 1977. The colours are usually smoky brown but also occur in pink, red, green, blue and on rare occasions, white.
Dravite – Also known as brown Tourmaline, Dravite is rich in sodium magnesium. Its varieties include vanadium Dravite and green chromium Dravite.
There are also numerous colour varieties of Tourmalines: Achroite (colourless Tourmaline), Rubellite (red Tourmaline), Indicolite (blue Tourmaline), Verdelite (green Tourmaline), Siberite (reddish-violet Tourmaline), Watermelon (pink core with green edges), Bi-colour, Tri-colour and Paraiba (neon coloured Elbaite Tourmaline).
Tourmaline is believed to be one of the powerful, protective stones in existence, within the metaphysical community. The ancient Egyptians believed that Tourmaline got its amazing colours because they emerged from the Earth’s surface while passing through a rainbow on the way.
This gemstone is also believed to protect the wearer against pollutants, toxins, blood diseases, negative emotions and thoughts. Tourmaline is also associated with power.
Importance of Tourmaline in astrology
Within astrology, Tourmaline is considered to be the birthstone for the zodiac sign of Libra. It helps in overcoming limited ways of thinking and is associated with all energy centres – chakras – in the body. It is believed to clean and charge the electromagnetic system of the body. Tourmaline is also believed to strengthen the nervous system and regulate blood flow.
It is believed to hold a wide-range of physical and mental healing properties. It is considered to be good for healing problems of the digestive system, stress etc. It is believed to strengthen bones and teeth. Some varieties of Tourmalines are believed to form a strong link between love and spirituality.
Physical and Optical properties of Tourmaline
Tourmaline has a hardness of 7 to 7.5 MOh and a hexagonal crystal system. It has a specific gravity of 3.06 (+0.20, -0.06). Tourmalines are usually recognised by its characteristic rounded triangular cross section of the crystals and have a lack of visible cleavage. This gemstone has a vitreous lustre.
Demand and Scope
The Paraiba Tourmaline is one of the most sought after and expensive gemstones on the market. It is known for its broad blue-green spectrum and can fetch up to $100,000 per carat. It is a high value/ high demand asset for modern jewellery design. With high demand for custom jewellery in upscale markets, the Paraiba Tourmaline is high in demand.
Known to withstand light and chemicals, Tourmaline is strongly pyroelectric. This means that when exposed to heat, it becomes electrically charged. When it is squeezed, it becomes piezoelectric.
Some of the most famous Tourmalines in history are the pink and red ones, that were shipped from California to China for Chinese Dowager Empress Tz’u Hsi because she was fond of the colour. Red Tourmalines, which were mistaken for rubies, can also be found on the crown jewels created for the coronation of Tsarina Anna of Russia Ivanovna. One of the “rubies” in the Russian crown jewels, the “Caesar’s Ruby”, is actually red (rubellite) Tourmaline.
Identification of Tourmaline
For practical identification of Tourmalines, click on the link below.
While most Tourmaline gemstones are not treated, sometimes they are treated with heat and irradiation. Radiation treatments are done with high energy electrons. Brownish, pink Tourmalines from Brazil are treated with heat to remove colouration and radiated to produce a pure, rose red.
The prices of tourmaline vary tremendously, depending on the variety and quality. Paraíba tourmalines are the most expensive, which may reach tens of thousands of dollars per carat. Chrome tourmalines, rubellites and fine indicolites and bi-colors may sell for as much as $1000/ct. or more. Other varieties are available for prices between $50–750/ct., depending on the richness of the color.
For learning pricing of Tourmaline, contact 9619057706 or click here