Paraíba tourmaline is a blue, bluish green to greenish blue, green or yellowish green tourmaline. Copper and manganese mainly cause its color, whatever its geographic origin.
In more detail
It was first found in the state of Paraíba, Brazil, in the late 1980s. Similar copper-bearing tourmaline later came from Nigeria and Mozambique. A tourmaline with only traces of copper and low color saturation is not called Paraíba. Paraíba tourmaline is commonly heated, and labs cannot always detect this treatment.
On a grading report
LMHC wording: Species: (natural) tourmaline. Variety: (color) paraiba (tourmaline). Origin is a separate line: Brazil, Nigeria, Mozambique, other or not determined.
Related terms
- Tourmaline: Tourmaline is a group of closely related mineral species with the same crystal structure. It has one of the widest color ranges of any gem.
- Origin report: An origin report gives a lab's opinion on the country or region where a gem was mined.
- Heat treatment: Heat treatment is controlled heating of a gem to change its color or clarity.
- Saturation: Saturation is the strength or purity of a gem's color, from grayish or brownish to vivid.
- Colored stone report: A colored stone report is a lab document that identifies a gem and states any treatment the lab detects. GIA's identification report describes the color but does not grade it.