Tourmaline is a gemstone found in various colors.
Illyrio Mopatis has tourmaline among his various rings.
The Tourmaline Brotherhood is a faction of merchant princes in Qarth.
The Tourmaline Emperor was a legendary ruler of the Great Empire of the Dawn.
Daenerys Targaryen has a vision of ghosts with eyes of amethyst, jade, opal, and tourmaline.
Xaro Xhoan Daxos gives Daenerys a thousand miniature knights carved of amber, amethyst, beryl, jade, onyx, opal, and tourmaline, with armor of silver and gold.