Paraíba Tourmaline

The original deposits are granitic pegmatites in northeastern Brazil: in 1989 and 1990 copper-colored blue to green elbaite was found in pegmatite pockets in the states of Paraíba (for example around São José da Batalha) and Rio Grande do Norte. Similar copper-bearing tourmaline was found in Nigeria in 2001 and in Mozambique in 2005; Mozambique's significant deposits have increased availability. GIA notes that the crystals are believed to form under very unusual conditions, with large amounts of trace elements such as manganese and copper.

The name depends on composition and color, which require laboratory testing. Under LMHC Information Sheet 6, tourmaline with only traces of copper, low color saturation or a color outside the defined range is not called Paraíba tourmaline, nor is iron-rich copper-bearing tourmaline whose polarized spectrum shows a 700 nm absorption band higher than the copper-related 900 nm band. The Japanese AGL allows the alias "Paraíba tourmaline" for copper-bearing tourmaline only together with an analysis report. Some stones contain inclusions of native copper. Geographic origin (Brazil, Nigeria or Mozambique) can be assessed by laboratories using trace-element chemistry, and heat treatment is common but not always detectable. Mindat warns that some stones sold under the name appear to be ordinary green tourmaline.

GIA rates tourmaline 7 to 7.5 on the Mohs scale and generally suitable for everyday wear. It is usually stable to light and most chemicals, but heat can be damaging. Clean with warm, soapy water and a soft brush; ultrasonic and steam cleaners are not recommended.

Paraíba tourmaline reached the market in the late 1980s, and its neon blues and greens drew wild demand, especially in Japan. Prices for top-quality stones of 3 to 5 carats rose rapidly to over $10,000 per carat, higher than any tourmaline before. Material was informally named after the Brazilian state; after similar copper-bearing tourmaline appeared in Nigeria (2001) and Mozambique (2005), use of the name for non-Brazilian stones became disputed until laboratories standardized it as a variety name.