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Is it really Paraíba?

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I have this 13.64 carat stone in my possession, with an opportunity to purchase it. It’s being represented as Paraíba tourmaline from Mozambique. I’ve studied it carefully and I can’t find any inclusions or, significant problems other than I personally don’t think the color is very attractive. Another thing that isn’t very attractive is the price, so I want to be very careful to get all the advice I can from members with more experience than I have with tourmaline. I have a programmable kiln which I use routinely for heat treating Tanzanite, and some occasional aquamarine. I have used it successfully to treat Rubilite tourmaline that was too dark to be usable, and ended up with some beautiful shades of fuchsia or hot pink. My questions are, 1. Is this piece of rough in fact Paraíba tourmaline? 2. If heat treated, what color would be expected, and can anyone offer information on heat treating ramp up time, maximum temperature, and how long to hold the stone at max temp? 3. What is a reasonable price to pay for a piece of rough like this?

Thanks for any help you can provide!

I could be very wrong but at first glance I think cordierite if not that then sapphire … but it’s pleochroism from violet blue to gray exhibited in pictures scream iolite … have you tried to do a spot reading RI on it or use a dichroscope and check its Pleochroism ?

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I have not done those tests because I don’t yet own the equipment. I know the person selling this piece and have good reason to believe he is telling me what he believes to be true. I’m also confident this piece is tourmaline. My concern is whether or not it’s a fairly run of the mill, pale green tourmaline, or the rare and expensive Paraíba tourmaline, and of course any information I can get on what it might look like after heating.

Assuming it is tourmaline as represented, it is not the high-grade color of heatable Paraiba-type color. But it may become a very fine color indeed, but to my eye lacks the intensity of color I’d want as a starting point. If you’ve heated before, you know there are always variables in heating tourmaline, not the least of which is what color the stone will become. If the money is substantial, it would be best to find someone who is an expert at heating tourmaline from Mozambique, pay them a consulting fee if necessary and discuss it with them. (Sorry, I don’t have that expertise.)

Only a lab like GIA has the necessary equipment to determine if this is “copper bearing” tourmaline, or not.

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If the origin is Mozambique and it contains copper it would be a Cuprian, not Paraiba. There is a huge price difference between the two. As an example, according to the Gemguide, if we take a fine quality (7) grade Paraiba of a cut stone weighing between 3.00 and 3.99ct the price would be $22500 per carat. The same stone but a Cuprian from Mozambique would be $7000 per carat which ties in with the prices we are seeing in South Africa for the Mozambique material. Unfortunately I am not able to give you an opinion about heat treating.

I’m not arguing. I only know what I can read, and that’s why I ask the question. Here is what I can read on the IGS website.

In 1988 exceptionally bright colored tourmalines were discovered in Paraíba, Brazil. It was determined that they were elbaite tourmalines and the intense coloring was due to copper. They also contained manganese and often a bit of bismuth. These stones generated great excitement and prices soon went over $20K per carat.

Soon after the original discovery, similar tourmalines were found in Brazil’s Rio Grande Do Norte state, just north of Paraíba state. This new find was also described as “paraíba tourmaline.”

In 2001, more copper colored tourmalines were discovered in Nigeria. Generally, the Nigerian gemstones were not as vivid as those from Brazil, although the range of colors did overlap. With the proper equipment, the Nigerian material can be distinguished by its lead content, which the Brazilian material lacks.

A couple years later, still more copper bearing tourmalines were discovered, this time in Mozambique. Their colors are much closer to those of the Brazilian, but their chemical composition is much more complex, with varying amounts of copper, magnesium, lead, and bismuth. A large number of these tourmalines do not contain any lead and have compositions that overlap those of the Brazilian tourmalines.

The Name Game – What is a True Paraíba Tourmaline?

From the beginning, the trade labeled these Paraíba tourmalines. The Rio Grande Do Norte tourmalines were also called paraiba.

Naming the Nigerian gems was a bit of a problem. Many would like to have them called “paraíba like,” or “Cu or copper bearing” tourmalines. Unfortunately, a lot of the Nigerian material was mixed with the Brazilian early on and the distinctions were confused. Next we had the addition of the Mozambique stones. These were commonly called “paraíba tourmalines from Mozambique.”

The chemical differences between the sources are so slight that it is often impossible to determine the origin. Visually, the best samples from Nigeria or Mozambique had colors that were as vivid as the ones from Brazil.

In 1999, before the Nigerian discoveries, the World Jewellery Confederation, (CIBJO,) modified their rules, allowing “paraíba” as a valid trade name. Traditionally, minerals often receive their name as a reference to the place where they were first encountered, so calling all the copper bearing elbaite tourmalines “paraíba” was easily accepted.

In February this year, (2006,) at the International Gemstone Industry Laboratory Conference the term “paraíba tourmaline” was adapted as a variety name, regardless of geographic origin. In April, the International Laboratory Manual Harmonization Committee also accepted the new terminology.

As a result of these recent events, most international gemological laboratories are calling all copper containing elbaite “paraíba tourmaline.” Many lab reports note that this is a variety name and does not necessarily denote origin.

The American Gem Trade Association, often at the front of ethical issues, has revised their reporting procedures. As of June first, AGTA reports will contain the following information:

  • SPECIES: Natural elbaite tourmaline
  • VARIETY: Paraíba tourmaline
  • ORIGIN: the source, (if known,) or not determined
  • COMMENTS: the variety name paraíba is derived from the locality in Brazil where it was first mined. its geographical origin has not been determined and therefore could be from Brazil, Mozambique, Nigeria or another locality.

And this from a different source. (There are many others of the same opinion.)

In 2006, the LMHC (Laboratory Manual Harmonization Committee) agreed that “Paraiba” should refer to a type of tourmaline, and not indicate a geographic origin. The term “paraiba” should not be capitalized (as it is in the name of the Brazilian state). Therefore, the term “paraiba tourmaline” may now refer to gems found in Brazil, Nigeria, and Mozambique, and in other places where new deposits of copper-bearing tourmaline may be found in the future.

The best advice you got above is to send it to GIA for a report. They can tell you if it is from African or Brazilian (Paraiba). If the seller is not willing to wait for this to be done, at your expense, then don’t buy this rough.

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In any case, the author, you need to do a comprehensive, in-depth examination! and best of all at the GIA!
But I’m 80% sure that you do not have Touribaline Paraiba, but it may well be another mineral. including the above-mentioned Cordierite (Iolite)

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