Mineral Family: Cyclosilicates

Chemical Composition: NA (Mg, Fe, Li, Mn, Al )3Al6(BO3)3Si6O18(OH,F)4
Cleavage: Indistinct
Color: Black
Crystal System: Hexagonal/triagonal
Form/Habit: Prismatic, acicular
Fracture: Uneven, small conchoidal, brittle
Gravity: 2.82-3.32
Hardness: 7-7.5
Luminescence: Blue (short wave)
Luster: Vitreous
Streak: White
Transparency: Transparent to opaque

Where does Tourmaline come from?

Tourmaline Placeholder
Tourmaline

Tourmaline is found around the world, with many of the most stunning examples coming from Brazil.  While Schorl is reliably black, Dravite and Elbaite can appear in a rainbow of colors.

  • Dravite comes from Australia, Austria, Brazil, India, Italy, Nepal, Switzerland, Tanzania, and the United States
  • Elbaite comes from Afghanistan, Brazil, Italy, Madagascar, Mozambique, Myanmar, Namibia, Pakistan, Russia and the United States
  • Schorl comes from Argentina, Brazil Canada, Czech Republic, France, India, Italy, Namibia, Pakistan, Portugal, Sweden, and the United States

What is Tourmaline?

Tourmaline is a generic term which refers to 11 varieties of borosilicate minerals that can be any color of the rainbow.  Silicate minerals are the largest family of minerals, including more than 25% of all known minerals and 40% of all common minerals. In addition to being a major part of the Earth’s crust, Silicate minerals have also been found on the moon and in meteorites. Silicates are minerals which contain the elements Silicon (a light gray shiny metal) and Oxygen (a colorless gas). Together, these two elements form a tetrahedra – a shape similar to a pyramid – with a Silicon atom in the center and Oxygen atoms at each of the three corners. These tetrahedras connect with other chemical structures, in six different ways, to form various minerals and rocks. There are six main groups of Silicate minerals, and these main groups are further subdivided into a variety of secondary subdivisions, such as Quartz and Feldspar. Another such subdivision is Borosilicates, which are silicate minerals which contain the element Boron (a brown metal).  While Black Tourmaline is likely to be Schorl, other colors like red, pink, green, yellow, blue and purple can be Dravite or Elbaite.

How is Tourmaline formed?

Tourmaline is created when liquid magma from a volcanic explosion cools down and transforms into igneous rocks. During this cooling down period, borosilica acid shifts from being a gas/liquid into a solid compound, called Tourmaline. Most species of Tourmaline are found in Pegmatite, a type of ignenous rock which typically develops underwater

How is Tourmaline mined?

Tourmaline is a fairly common mineral, but gem quality crystals are relatively rare, and found almost exclusively in Pegmatite. Numerous mines exist whose primary purpose is finding gem-quality Tourmaline.

Is Tourmaline real?

Opaque Tourmalines are natural, enhanced only by cutting and polishing. But transparent Tourmaline can be heat-treated to brighten the color.  For example a dark green Tourmaline might be  heat-treated to become a vivid emerald green.  Such treatments primarily occur in the fine gemstone jewelry industry. Lab-created Tourmaline also exists.  But it is typically used for research purposes and so is not readily available to the general public.