Tourmaline is one of the most popular and favoured gemstones among jewellery designers, offering a wide variety of colours often found in a single stone.
It easily adapts to fashion trends and can be combined with most metals. But you need to know a little more about the technical aspects and trading of tourmalines if you are not experienced in buying them.
Tourmaline is a borosilicate mineral that often contains chemical elements such as aluminium, iron, magnesium, sodium, lithium, copper and potassium. It is these chemical elements that give tourmalines their colour.
It is a stone that fetches very high prices on the collector’s mineral market and as a gemstone.
“Tourmaline” is not actually a mineral, but rather a generic term applied to the members of the Tourmaline group, which consists of 33 different minerals with a wide variety of compositions.
The most common tourmaline is schorlite, which has a black macroscopic colour and is therefore known commercially as “black tourmaline”.
Due to the wide variation in colour and some variations in habit, there are about two dozen varieties of tourmaline.
Distinguishing the members of the tourmaline group under the microscope is difficult, almost impossible, and requires the use of other analytical techniques.
Not all types of tourmaline are used in jewellery. Because of their physical and chemical properties, many types of tourmaline are used in industry.
Among the various families of tourmalines, the elbaite is the one that contains the gems used in jewellery. Their trade names are related to their colour:
Tourmaline mines can be found in several countries. Brazil is one of the largest producers of this gemstone. Tourmalines are known by different names in different countries.
Types of Tourmaline in nature
In addition to different colours and shades, the brightness and colour of the stones can vary according to the intensity of the light and the point of view. Each version is unique. Below we’ll tell you a little more about their variations.
Tourmaline is a group of minerals rather than a single species.
Of the 11 existing types of tourmaline, the elbaite varieties are the most widely used as gemstones.
Tourmalines of a single colour are very rare. Different shades and even colours often occur in the same crystal.
The variety of tourmaline with a red centre, white inner layer and green outer layer is popularly known as watermelon tourmaline.
Nowadays, tourmalines are identified by the name of the colour after the word tourmaline, for example pink tourmaline.
Another classification is the locality, such as Paraíba Tourmaline, discovered in the mid-1980s in the interior of the state of Paraíba.
Tourmaline deposits are found in pegmatites and alluvial deposits mainly in Namibia, Brazil and the USA, followed by Russia, Myanmar (formerly Burma), Sri Lanka, India and Madagascar. In Brazil, the state of Minas Gerais stands out, but tourmalines are also found in Ceará, Goiás and Bahia.
In 1978, in the parish of Conselheiro Pena (MG), several rubellite crystals weighing tens of kilos were discovered.
- Dravite (brown): These are stones with a high concentration of magnesium. Their name comes from their discovery in the river Drava, between Austria and Slovenia.
- Schori (black): These are stones with a high sodium content.
- Acroite: colourless or nearly colourless; very rare
- Elbaite: These tourmalines are rich in aluminium, lithium and sodium.
The Elbaite Tourmaline, within this variation of aluminium, lithium and sodium, includes the following stones:
1. Paraíba Tourmaline
The Paraíba Tourmaline was discovered in the 1980s, specifically in the town of São José da Batalha. Because it contains traces of copper and manganese, its colour varies between blue and green. It is also a stone known for its intense brilliance – after cutting, Tourmaline becomes even more vivid.
2. Blue Tourmaline
Blue Tourmaline has variations of darker or lighter shades – it is also known asBrazilian Sapphire. Like theParaíba Tourmaline, it is a rare gem.
3. Black Tourmaline
Black Tourmaline has a dark colour due to its high concentration of calcium.
4. Yellow Tourmaline
Yellow Tourmaline is also known as Canary Tourmaline. It was one of the most recent discoveries compared to the others. Its yellow colour has orange tones, but there are also variations of this stone with orange and brownish tones.
It is believed that yellow tourmaline helps to open paths and therapeutic treatments.
5. Red and Pink Tourmaline
Also known as rubellite, pink tourmaline comes in a variety of shades depending on the concentration of manganese in its composition. Some varieties are so intense that they can be mistaken for ruby due to their reddish hue.
It is one of the most beautiful variations of the gemstone as it has a more vivid shade of bright pink. Tourmaline can also be found in some multicoloured versions.
6. Green Tourmaline
Green tourmaline, also known as verdelite, has a high concentration of iron and titanium and an intense lustre.
It is often confused with Emerald – this is due to both the colour and appearance of the stone.
Because of its beauty, it is one of the most commonly used stones in jewellery, and its shades vary – they can be lighter or darker.
7. Colourless Tourmaline
Colourless or nearly colourless Tourmaline is very rare.
