Manjari Sihare of Saffronart explores why Tourmalines find a special place in the hearts of gemstones collectors
New York: Tourmalines seem to have special place in the hearts of gemstone enthusiasts, primarily for two reasons – first, that these gems can be found possibly in every color one can think of, and secondly, that these stones are affordable to most.
The word tourmaline is derived form the Sinhalese word tura mali, which means ‘mixed stone’. Tourmaline is not a single mineral but a group of minerals related by the close similarity of their physical and chemical properties.
Tourmalines are mixed crystals of aluminium boron silicate, and even slight changes in their chemical composition cause completely different colors. There are tourmalines in single colors, while some may exhibit two colors in a single stone. Certain tourmalines may even change color when the light source changes from natural to artificial. Different colored tourmalines are known by different names. Tourmalines that are red in natural and artificial light are known as rubellites; red tourmalines that turn pink when the light changes are called a pink tourmalines; blue tourmalines are known as indicolites; yellowish brown tourmalines are known as dravites; green tourmalines are known as verdelites; and black tourmalines are known as schorl. Tourmalines with two colors are bicolored tourmalines, while those with more are known as multicolored tourmalines. A particularly attractive type of tourmaline is known as the watermelon tourmaline because it has a red center and is surrounded by a layer of green. When cut into, these tourmalines are green on one side and red on the other.
The proper lighting conditions for tourmaline will depend on the color variety. Reds, oranges and yellows generally look best under incandescent light, while greens, blues and violets appear prettier under daylight. When buying any gem, it is always a good idea to examine it under a variety of light sources.
Tourmalines are found all over the world, with the major mining areas in Brazil, Sri Lanka, Nigeria, Zimbabwe, Kenya, Tanzania, Mozambique, Madagascar, USA, Pakistan and Afghanistan. Although they are so abundantly available, tourmalines of exceptional color and quality are rare. The value of a tourmaline is determined by its color, undertones, and clarity.