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About Tourmaline
 Tourmaline is a beautiful gemstone which comes in many colors including green, blue, red, pink and mixes of multiple colors. Color variations in the same stone are referred to as bicolor or tricolor tourmaline. This gem is popular with both gem and crystal collectors. Both the rough crystals and the cut gemstones can be visually stunning. Tourmaline is mined in Brazil, Africa, Madagascar, Afghanistan, Pakistan Russia, and the United States. |
 Bi-color tourmaline is usually a mix of greens and reds but there are others. The clarity characteristics vary greatly with some gems being eye clean and others very included. Inclusions are common in the area of color change. The rough material is often cut in long shapes to accentuate the change in color. |
 Pink Tourmaline and Red Tourmaline (Rubellite) a re colored by traces of manganese. Pink tourmaline ranges from a soft pastel color to an intense vivid pink.
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 Rubellite is generally a much more color saturated gem than pink tourmaline. However, It can be a judgment call if the color falls between the lighter reds and the darker pinks. |
 Green and blue/green tourmaline is colored by traces of iron and possibly titanium. Colors range from very light to very saturated greens. |
 Paraiba Tourmaline is rare form of Tourmaline with vivid neon colors of blue or green which is caused by traces of copper in its chemical structure. It was first discovered in 1988 in the state of Paraiba, Brazil. This was the only source of copper bearing tourmaline until 2001 when a new find was discovered in Nigeria and most recently in Mozambique. The color of this new material rivals that of the Brazilian Paraiba. There are different views on the naming of this new material. Some believe that only copper bearing tourmaline that comes from Paraiba should be called Paraiba. Others believe that all copper bearing tourmaline regardless of origin should be called Paraiba. The colors of untreated copper bearing tourmalines include greens, blues, purples, and mixes of those hues. The purple material will change to the greenish or bluish hues when heated. Technically the purple hues cannot be called Paraiba because the description of Paraiba only includes greens and blues. However, if they are heat treated and turn one of the green/blue hues then they can be called Paraiba. Much of the tourmaline regardless of color is heat treated resulting in the neon colors for which it is so prized. Large gems had been scarce until the African discoveries. Gems in excess of 70 carats have been fashioned and are wholesaling for as much as $15,000 or more per carat. |
Physical Properties of Tourmaline |
| Color |
Various |
| Refractive Index |
1.62 – 1.65 |
| Chemistry |
Sodium Aluminum Borosilicate |
| Hardness |
7.0 – 7.5 |
| Specific gravity |
3.02 – 3.26 |
| Crystal Group |
Hexagonal |
| Primary sources |
Brazil, Mozambique, Madagascar, others |
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