Composition: Borosilicates containing one or more of the following elements: calcium, potassium, sodium, aluminum, iron, lithium, magnesium, manganese, chromium.
Nomenclature: Said to be a corruption of the Singhalese word "tournamal" or "turamali."
Industrial Uses: Gemstones, carvings.
Additional Notes: A group of chemically- and structurally-related minerals. Many varieties of tourmaline exist, based upon color and chemical differences.
Brazil : Scott 2198 : 50 centavos : 12 Jul 1989
Tourmaline
Comoro Islands : Scott 930i : 375 francs : 1998
Indicolite (tourmaline) ["Indigolite" on stamp]
Kenya : Scott 107 : 2 shillings : 13 Dec 1977
Tourmaline
Switzerland : Scott B284 : 20+10 centimes : 1 Jun 1959
Tourmaline
United States : Scott 1539 : 10 cents : 13 Jun 1974
Tourmaline; Quartz