Tourmaline is a collection of silicate boron minerals which come in a spectacular array of colors. They are comprised of manganese, iron, copper and titanium, and their beauty and rarity has long made them a fixture in high in jewelry and watches.

Characteristics

Tourmaline is mined all over the globe, from Brazil to Africa and South Asia. It is considered a stone which is semi-precious, with some variants surpassing diamonds when it comes to rarity. Unlike other gems, which typically come in a single color, tourmaline comes in multiple colors, sometimes three in a single stone. The color and combination partly determines its value. For example, green Paraiba or neon blue Brazilian stones are exceptionally rare and can command prices of up to $10,000 for a single carat.

Another factor which sets tourmaline apart from other stones is its ability to change color. This change occurs when the stone is viewed at different angles, and is the result of a scientific phenomenon called pleochroism. The crystal structure combined with the setting and slicing of the stone maximizes this effect, which is considered by jewelers to be a skilled art.

Shopping For Tourmaline

Tourmaline is classified into multiple species, with the most popular being Dravite, Elbaite, Uvite and Schorl. The Schorl tourmaline stones will usually be black, but may also display a brown or blue tint. Elbaite is named after Elba, a Mediterranean island and these stones range from red to pink and green. They are well suited to jewelry. Dravite tourmaline is rich in magnesium and displays darker colors such as brown, black or a dark yellow. Uvite stones will usually appear in reddish brown or green. The most popular tourmaline is watermelon, which has a mixture of green and pink, resembling the fruit after which it is named.

When it comes to hardness, tourmaline has a rating of 7 or 7.5 on the Mohs scale, meaning it is quite hard (the highest rating is 10, which is reserved for diamonds). The high durability of tourmaline makes it well suited to heat treatment. Jewelers will often apply heat to the stone to alter their color or to boost the clarity. It is possible to darken or lighten the color using this process, and the heat application will usually require three days using specialized tools at temperatures which range between five hundred to seven hundred degrees Fahrenheit. An alternative to heat treatment is irradiation, which is rarely used.

How To Wear and Care for Tourmaline

Tourmaline is best worn in earrings, bracelets, rings or pendants. The gem cuts come in numerous varieties, and because of its hardness owners don’t have to worry about the cracks, breaks or chips which are common with other stones. The stones can appear in the shape of pears, octagons, rectangles and ovals, whichever you desire. When caring for tourmaline, be sure to keep it away from rapid temperature changes or sudden strong blows. While these stones are tough, they are not invulnerable and when cleaning them use a mild mix of water and dishwashing detergent.