STONE
Tourmaline
A gemstone family drawn from several species of the tourmaline supergroup and noted for exceptional colour diversity.
- Typical colour
- Nearly every colour
- Also known as
- Турмалин
- Birthstone
- October A modern tradition, not a property of the stone. GIA
FOUND IN TAJIKISTAN
Gem elbaite, including multicoloured crystals, comes from the miarolitic pegmatites of the Rangkul' field (Mika pegmatite), Eastern Pamir.
Mindat — Tourmaline from Rangkul' pegmatite fieldWHAT IT IS MADE OF
Mineral science
Physical and optical properties belong to the mineral species; see the mineral page for the full sourced profile.
What causes the colour
Tourmaline has one of the widest colour ranges of any gem. Iron and titanium produce greens and blues; manganese produces reds, pinks and possibly yellows; natural or laboratory radiation can create pink and yellow colour centres. Copper colours the vivid blue to green tourmalines from Paraíba, Brazil. Watermelon tourmaline is green on the outside and pink inside.
History and names
In 1554 Francisco Spinoza's expedition found what it called a "Brazilian emerald" — the first recorded green tourmaline crystal. Liddicoatite, a tourmaline species, is named after former GIA president Richard T. Liddicoat.
COLLECTION
Study views
SOURCE
GIA Gem Encyclopedia — Tourmaline