Tourmaline was first brought to Western Europe by the enterprising Dutch in the early 1700s. The gemstone was already being mined in Sri Lanka in this era, and the Dutch chose to rename the gemstone with a Sinhalese name (turmali).
The name supposedly reflects the many colors that seem to emanate from tourmaline when held up to the sunlight. Tourmaline has various degrees of transparency, and the variability can be substantial when you put different samples of tourmaline side by side.
There is both pale and dark tourmaline, and dichroism is more evident in the darker specimen. Tourmaline is notable for being accessible to electrified. This gemstone can become slightly electrified when you heat it, cool it or rub it. You can put small bits of paper around a tourmaline gem, and it will attract the bits of paper after rubbing. That’s how quickly it can establish a weak electrical field around itself.
How Many Types of Tourmaline?
Tourmaline comes in so many varieties of colour that you will find samples of it across the colour spectrum. Here are some of them:
- Rubellite – Rubellite is tourmaline in the red spectrum, and includes true red, pink, red-purple, orange-red, and so on. Some people believe that pink tourmaline should be stand-alone, but it usually is just called rubellite tourmaline just as well.
- Achroite – This is the colourless variety of tourmaline
- Indicolite – These are tourmaline specimens that are more on the blue, violet and greenish side.
- Paraiba – Paraiba tourmaline includes blue tourmaline with violet and green tints. It may also refer to deep blue tourmaline. All Paraiba tourmalines are mined from Brazil, in the state of Paraiba.
- Chrome – This is the most intensely green tourmaline around. What is interesting about chrome tourmaline is it coloured deeply not by chromium but by the rarer element vanadium. Vanadium rarely stays in one place long enough to form minerals or become part of minerals, so we can say that chrome tourmaline is up there in terms of rarity.
- Parti-coloured – These are tourmaline that has at least two visible colours. The most common combination is green and pink.
- Watermelon tourmaline – This type of tourmaline has a refreshing green and pink color combination. The body of the specimen will be mostly pink, ringed by green. Water tourmaline is usually cut in such a way that the layering of colors is displayed prominently.
Another exciting aspect about tourmaline is sometimes, it features chatoyancy or the cat’s eye effect. Tourmaline that shows this visual tendency is usually green, pink or blue.
The cat’s eye will generally show a gentle diffusion instead of a sharp one. Chatoyancy is a visual effect caused by internal inclusions in gemstones. It can appear in other types of gemstone, and the visual effect is often stated before the name of the gem. “Cat’s eye tourmaline” is an excellent way to name a sample that has a beautiful cat’s eye effect in it.
Tourmaline can further be categorized based on their chemical composition.
Tourmaline is a family or group of minerals that have close similarities when it comes to structuring but differ slightly in what elements are included in each one. For example, elbaites have more aluminium, sodium, and lithium. In some instances, copper comes into the mix. Elbaites are derived from pegmatites. A single pocket of elbaites in a natural setting can produce tourmaline of different colours.
Liddicoatite tourmaline has more calcium, instead of sodium. Liddicoatite is also derived from tourmaline and features internal patterns that have rich color, compared to other variants. This variety of tourmaline was baned after Richard Liddicoat.
Other varieties of tourmaline include uvite, dravite, tsavorite, “Savanna”, and schorl. Schorl is black tourmaline and has high levels of iron. Interestingly enough, schorl tourmaline is often used to manufacture mourning jewellery.
Tourmalines may undergo heat treatments to change their colours. A typical heat treatment that reaches at least 450˚ Celsius can change typically green tourmaline to emerald green. In some instances, depending on the imperfections of the gemstone, the colour may lighten instead of deepening. Tourmalines may also be irradiated to make them multi-colour, but remember that these effects will change or fade over time. Gamma radiation is used for irradiating different gemstones, not just tourmaline.
When looking at tourmaline, you may want to use the right kind of lighting so you can fully appreciate its multi-faceted nature and its colour. Generally speaking Red tourmaline, orange tourmaline, and yellow tourmaline look best when there is incandescent lighting. Green tourmaline, blue tourmaline and violet tourmaline reflect natural light best. When buying any kind of gemstone, we recommend examining it using different kinds of light so you can fully appreciate its characteristics.
There are some instances when you can only see the internal structure of a gemstone fully when the right kind of light is used. The most common inclusion that is visible to the naked eye is small fractures (which are standard) and needle-like formations inside the crystalline structure. While these may not be fully visible or even obvious when you look at a gemstone plainly, internal inclusions and flaws affect the value of gemstones, especially for tourmaline, which is considered a high-value gem.
The cut used for tourmaline will depend on its colour. Dual-colour tourmaline will be cut in such a way that the dualism in colour will be most apparent.
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Where is Tourmaline Found?
Tourmaline is found in a dazzling number of countries: Zimbabwe, Zambia, Vietnam, United States, Tanzania, Tajikistan, Sri Lanka, Russia, Pakistan, Nigeria, Nepal, Namibia, Myanmar, Mozambique, Madagascar, Kenya, India, China, Brazile and Afghanistan.
How Much Are They Worth?
The price of tourmaline in the market varies greatly depending on the quality and the type of tourmaline being sold. The most expensive thus far is the one that is mined in Paraiba, Brazil.
This command the highest value in the market, and stores will often charge as much as $1000 per carat of Paraiba tourmaline. More common tourmaline are more affordable, and they can go for anywhere from $50 to $750 per carat. The primary basis for the pricing of tourmaline is the depth and quality of its colour.