A miracle of nature.
One of the most beautiful gemstones on the planet is the incredibly complex gemstone, Tourmaline. Just one glance at its chemical composition and all but the scientists amongst us will quickly glaze over the formula.
So to find a piece of Tourmaline that makes the transition from one gorgeous colour to another is nothing short of a miracle of nature. But if Nature can do it once, why can’t she do it twice?
Why, if Tourmaline can be found in every colour of the rainbow, can’t it have several different colour combinations? There is no denying that the transition from bottle green to bubble gum pink witnessed in Bi- Coloured Tourmaline is one of the most beautiful, natural journeys on the planet, but why does it not occur with other Tourmaline colours? To find out the answer to this question I quizzed Brazilian gem expert Joas Salvador.
Joas explained that it’s not impossible to find Bi-Coloured Tourmalines that feature other colours, in fact over the years Joao explained that there had been a fair amount that traverse from a brown to green colour, but these had not been coming out of the ground in recent times. Other combinations such as red to yellow, however, are so rare that they tend to be snapped up by wealthy collectors. Joas told me that many Tourmaline miners in Minas Gerais knew one or two buyers of the incredibly rare colour combinations and normally these pieces would be sold over the phone before anyone else even got to see them.
Some of the finest Bi-colour Tourmaline comes from the Pederneira Mine in Minas Gerais, Brazil. The mine is owned by Saint-Clair Fonseca Júnior and on a recent visit to Brazil he showed me around his mine. I asked him how much Bi-Coloured Tourmaline the mine was currently producing. Saint-Clair explained that the gem was found in small pockets and that once they found a pocket they might have a good yield for a few days, but then they could go months, sometimes years before another lucrative find is discovered. This erratic supply explains why my company went three years without being able to source a single deal for the gem and such is the international demand for Bi-Coloured Tourmaline, that it took a long, drawn out negotiation with Saint-Clair to get him to sell a small parcel that he had recently unearthed.
The gem’s crystal structure tends to be thin and long which results in the gem normally being faceted as a baguette or octagon shape. Because lapidarists will always try and show the maximum shift of colour, the outcome is often a very long gemstone. Most Bi-Coloured Tourmalines are set into pendants, however on the odd occasion a pair of similar pieces are cut, a jeweller will try and set them in long, dangling earrings.
When eye-clean, a Bi-Coloured Tourmaline can sometimes demand over a thousand dollars per carat and even heavily included pieces are often traded at over one hundred and fifty dollars per carat.
The main difference between Bi-Coloured Tourmaline and Watermelon Tourmaline is that the latter tends to have pink in the middle with a surrounding circle of green, hence its name. Whilst Bi-Colour Tourmaline is faceted, Watermelon Tourmaline is normally cut into thin discs.
Other areas where Bi-Coloured Tourmaline is also mined include Nigeria, Madagascar and Afghanistan.