What is Tourmaline
The tourmaline group refers to a number of related types of minerals and varieties. It tends to crystallize in hard rocks like granite or quartz, so it can be difficult to mine without breakage. Colors are diverse, and a single crystal can contain multiple colors. Concentrations of iron, magnesium, nickel, calcium, chromium, and cobalt create the rainbow of colors. It is mined in Brazil, Madagascar, Sri Lanka, Russia, Italy, Switzerland, throughout Africa, and in California and Maine in the US.
Due to its variety of colors, tourmaline has often been misidentified as other gemstones such as amethyst, emerald, peridot, ruby, and topaz.
Tourmaline Color and Characteristics
Tourmaline gems may be bi-colored and even tri-colored. Inclusions depend on the variety – green is usually free of inclusions, Red, pink, and watermelon can be more heavily included, all other varieties typically have minor inclusions.
Heat treatment is used to enhance the colors and is considered permanent, although prolonged exposure to heat and light may cause the stone to fade.
Tourmaline has an interesting characteristic known as pyroelectricity or the piezoelectric effect. When the crystal is rubbed, it will become electrically charged and attract dust particles and small pieces of paper.
Following are gemstone types of tourmaline:
Paraiba: Intense green, blue, or violet
Schorl: Opaque black
Watermelon: Pink middle surrounded by green outer edges
Siberlite: Lilac to violet blue
Achroite: Colorless – very rare
Color determines the price in tourmaline. Pink and green are the most desired colors. Tourmaline is often paired with other precious and semi-precious stones in settings.
Tourmaline are easily cared for, requiring cleaning with gentle solution made specifically for jewelry or with warm soapy water. It is important to have your jewelry professionally cleaned and checked three to four times a year. When not worn, tourmaline jewelry should be stored in a jewelry box lined with soft fabric.