Tourmaline is famous for a simple reason: no other gemstone comes in as many colours. The same mineral species produces vivid pink, green, blue, yellow, black, and colourless crystals, sometimes several colours banded within a single crystal.
Chemically, tourmaline is a complex boron silicate, and its structure can accommodate a wide range of trace elements, including iron, manganese, chromium and titanium, each one shifting the colour in a different direction. That chemical flexibility is exactly why the tourmaline group produces so many named varieties, from watermelon to indicolite to rubellite.
Tourmaline crystallises in long, striated, prism shaped crystals, usually with a rounded triangular cross section, and it forms in pegmatites: granite bodies that cool slowly enough for large, well formed crystals to grow. Afghanistan and Pakistan's pegmatite fields, particularly around Nuristan and Gilgit Baltistan, have produced some of the finest tourmaline specimens of the last few decades.
On the Mohs scale, tourmaline sits at 7 to 7.5, hard enough for jewellery use and stable enough to last for generations as a mineral specimen.
Browse our full Tourmaline collection to see the range for yourself, from single colour crystals to the more dramatic bi-colour and tri-colour material.