- Pink Seductress: The pink variety of tourmaline is known as “rubellite” and owes its gentle shimmer to traces of manganese. Single-coloured, deep red crystals are extremely rare. In contrast, spectacular flows of colour — from red and orange to brown, yellow and green in a single crystal are not unusual.
- Radiant canary yellow: The radiant yellow stones are also referred to as “Canary” tourmalines. The attractive natural colour is due to traces of manganese and/or titanium, as well as iron.
- Greener than green: “Verdilite” is the name for green tourmalines. The colouring is due to chrome and/or vanadium.
- Out of the blue: Traces of iron are what causes the deep blue of tourmaline. Stones in all shades of blue are called indicolites.
Good to know
When struck by light, tourmalines display quite a high level of birefringence and are recognisable by their multi-hued effect.
Mining of the most valuable tourmalines is a very lucrative business. Most of the stones produced today come from locations in Brazil and Africa.
Endless play of colours
The most important commercial producer of tourmaline is Brazil, a country where the gemstones can be found in all the colours of the rainbow — frequently even in a single mine and in the same seam as the host stone, pegmatite.
In top form
The longish, rod-like, triangular structure of the crude tourmaline crystals is important, as their characteristics are largely responsible for the subsequent shape of the stone.
A colourful inner life
Tourmaline features both longitudinal and lateral colour flows. Three-coloured crystals, appearing green on the outside with a white layer below and a red core are commonly referred to as “watermelon tourmalines”.
Classic and exotic
The name tourmaline derives from the Sinhalese word “turamali” (stone with mixed colours). However, the mineral’s entire range of colours and its varying forms of appearance were not studied by scientists until after 1800.
With a hardness of 7 1/2 on the Mohs scale of mineral hardness, tourmaline occupies a position between quartz and topaz. Polishers use the effect of dichroism (different colours of a crystal depending on perspective), which is particularly strong in tourmalines, to achieve the ideal stone colour.
Tourmalines can be charged with electricity — which is the reason for their historical function as ash removers: Ash can be “drawn” from tobacco pipes using tourmaline crystals thanks to the rods’ powers of attraction. Because of this property, jewellery with tourmalines should be cleaned frequently.