Tourmaline is an important group of complex gem-quality boron silicate minerals. This fine stone can be found in a multitude of colours : “from black to bluish-black, dark brown, yellow, medium brown, blue to neon blue, lime to dark forest green, red and reddish purple, yellow, pink, and colorless”. Most of the tourmalines are natural, not treated. However, some can be heated or irradiated to improve its colour. My favourites are pink, paraiba and watermelon tourmalines.
These stones are found in “Africa, Afghanistan, Australia, Brazil, Kenya, Madagascar, Mozambique, Nigeria, Pakistan, Siberia, Sri Lanka, Tanzania, the USA, and Zimbabwe”. Furthermore, the name “tourmaline” comes from the Sinhalese term “turmali” meaning the “stone with various colours”. Besides, since Antiquity, this fine stone is reputed to bring “an unsual wealth into knowledge and spiritual forces”. According to the lithotherapy, tourmalines have positive and beneficial properties.
Elizabeth Locke ring, Marie Hélène de Taillac rings and Temple St Clair earrings.
Sources : http://crystal-cure.com/article-tourmaline.html