Iroishi Checker
No. 097 / 141

Paraiba Tourmaline

パライバトルマリン · ぱらいばとるまりん
NaturalBlue
Gemological dataPROPERTIES
Hardness7-7.5
Specific gravity3.10
Refractive index1.620-1.650
Crystal system六方晶系(三方晶系)
Color rangeCOLOR RANGE

The signature 'electric' or 'neon' blue-green to turquoise, sometimes pure neon blue, sometimes leaning greener. The hallmark is a fluorescent-looking glow that no other tourmaline shows.

UV responseFLUORESCENCE
Long-wave
365 nm
Generally inert; rarely a very faint glow
Short-wave
254 nm
Inert
Typical inclusionsINCLUSIONS
  • nclusions
  • Fine needle-like growth tubes parallel to the c-axis
  • Hairline fractures and partially healed fingerprints
Optical characterOPTICAL TRAITS
  • Doubly refractive with clearly visible at 10×
  • Strong dichroism: neon blue-green and pale green
What to look forID POINTS
  1. 01The 'glowing' quality of the color is the single best Paraíba cue — no other tourmaline does this
  2. 02Copper detection by EDXRF in a gem lab confirms Paraíba family membership
  3. 03Strong separates it from singly refractive blue stones (spinel, glass, synthetic blue corundum)
Stones it gets mistaken forSIMILAR STONES
Care & handlingCARE
  • Mohs 7–7.5 — durable enough for daily wear in a protective setting
  • nclusions that can rupture
  • Use lukewarm soapy water and a soft brush
Market notesMARKET
PRICE RANGE

Roughly $3,000–$10,000 per carat for commercial Mozambique stones, $20,000–$50,000+ per carat for fine Brazilian material, and over $100,000 per carat for top unheated Batalha stones at auction.

Note: Origin determination matters enormously: Brazilian material commands a multiple over Mozambique or Nigerian stones of the same color. Always require a reputable lab report stating both origin and treatment status for any high-value purchase. Heat treatment is common and disclosed.

BackgroundBACKGROUND

Paraíba tourmaline is an elbaite where copper (and sometimes manganese) produces an unmistakable glowing neon blue to greenish-blue. It is a member of the tourmaline group but is priced and graded apart from all other tourmalines. The 1989 discovery in Paraíba state, Brazil, was followed by similar copper-bearing deposits in Nigeria (2001) and Mozambique (2005), and LMHC has since approved the trade name 'Paraíba-type' for all three sources.

Origin & historyORIGIN & HISTORY

Origins

Brazil's Batalha mine in Paraíba state produced the original, most saturated material — now nearly mined out and the most expensive per carat. The neighbouring Rio Grande do Norte state still supplies a trickle of Brazilian-source stones. Nigeria came online in 2001, and Mozambique opened the largest modern deposit in 2005 — Mozambique stones tend to be cleaner and larger but slightly less neon.

History

Heitor Dimas Barbosa spent over a decade prospecting hills in Paraíba state on a hunch that something extraordinary was buried there. His 1989 discovery of copper-bearing tourmaline shocked the trade — prices jumped from a few thousand dollars per carat to tens of thousands within a year. The stone remains one of the great modern discovery stories in gemology.

Lore & symbolism

Paraíba has no traditional birthstone or zodiac association — it is too new. In modern lore it has come to symbolise vision, breakthroughs, and creative courage, fitting its discovery story.

OBSERVATION TOOLS · 4 ITEMS

Tools to confirm this stone

Tools that help confirm Paraiba Tourmaline. Tap any item to jump to the matching section on the gem tools page.

References
最終確認日
2026年4月28日
参 考 文 献

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