What Is in Tourmaline Crystals?

What is Tourmaline?

• Tourmaline is a complex silicate mineral formation, usually occurring in crystal form, that is composed mainly of boron and aluminum but also has sodium, magnesium, iron, silicon, fluorine and sometimes lithium. Tourmaline crystals are three sided and have striations running lengthwise.

Where areTourmaline Crystals Found?

• Tourmaline crystals form in igneous rocks such as granite and metamorphic rocks such as marble and schist. Crystals are currently mined in Brazil, Africa, Sri Lanka, Madagascar, Afghanistan and Pakistan.

Types of Tourmaline

• The most common type of tourmaline crystal is black, or schorl. Other varieties are dravite (brown or yellow) and elbaite -- which can be pink or red (rubellite), blue (indicolite), green (verdelite), and clear (achroite).

Schorl, or Black Tourmaline Crystal

• Schorl tourmaline crystal is black because its mineral structure contains a larger amount of the element iron than any other element.

Dravite

• Dravite tourmaline crystals are dark to pale brown or yellow because they contain the largest amount of the elements magnesium and sodium in their structure.

Elbaite

• Most gem-quality tourmalines are color varieties of elbaite, named after the isle of Elba. All elbaites, whether blue, green, clear, red, pink or the pink-and-green variety called "watermelon," are rich in lithium, sodium and aluminum. Rubellite is the most highly prized of all elbaite varieties.