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MissMagpie
07-12-2008, 01:17 AM
What's the difference between paraiba toumaline and cuprian tourmaline?

I know they both come from the same area, that paraiba contains copper and manganese and that the "curpian" bit obviously means copper... Does that mean that cuprian tourmaline doesn't contain manganese? Or is there some other difference?

Thanks, Gav! (Or anyone else who knows the answer... Meeshoo...?)

Meeshoo
07-12-2008, 05:50 PM
Gav - feel free to correct me if I'm wrong .................

Cuprian Elbaite Tourmaline (sometimes just Elbaite Tourmaline) is the name given to most Tourmaline found in Mozambique, Nigeria etc. However, there is a sub-category called "Paraiba" Tourmaline. This is reserved only for those gemstones that meet the "Paraiba" criteria i.e. neon, intensity of colour, and blue, green or purple.

Cuprian Elbaite Tourmaline can be found in lots of colours, pink, peach, pale green, brown, yellow, orange, grey, blue, yellowie green etc etc. but don't have the neon intensity of the gems called "Paraiba".

Here's an excerpt from the AGTA Gemological Testing Centre:

Does every tourmaline that contains a certain amount of copper/manganese qualify as a paraíba-type? In a word, no. The most important feature of a paraíba tourmaline is exactly that which made the gem famous in the first place – intensity of color. Thus if a gem submitted for testing lacks the necessary degree of color saturation, it will not meet the AGTA GTC's paraíba criteria, no matter what its chemistry. In such a case, color trumps chemistry.

Another issue is that of origin. While paraíba tourmalines were first found in Brazil's Paraíba State, stones of similar color and composition have now been found in the neighboring Rio Grande do Norte State (Brazil), Nigeria and Mozambique. Some purists have argued that the paraíba variety should be limited to Brazilian stones, but the decision of the LMHC was that this variety will be defined by color and composition, not country-of-origin. Upon request, member labs of the LMHC will identify the country-of-origin on their documents, thus satisfying all clients.

Hope that helps.

MissMagpie
07-12-2008, 06:21 PM
Thanks, Meeshoo.... But I'm still a bit confused. Some of the paraibas on offer seem quite a pale green and you would have to use a lot of imagination to describe them as "neon", while some of the cuprian tourmalines (particularly the yellow-green ones) look very vivid?

Meeshoo
07-12-2008, 07:22 PM
There's a very fine line between what you might class as Paraiba and what you wouldn't. Being neon and vivid/intense are different.

Look at these two links. The first is all Paraiba - you can see the colour and "neon-ness" screaming at you. The second link is blue/green tourmalines. Some are incredibly vivid but none have the neon quality although are stunning and incredibly vivid.

http://www.paraibainternational.com/products.php?category=3&page=all&sort=
Look at product code id 1426 - for me that doesn't cut the mustard!

http://www.paraibainternational.com/products.php?category=7&page=all&sort=
Look at product code id 537 - I bet you lots of places would class that as Paraiba.

Klosblue
07-12-2008, 07:26 PM
I did a search on the web for Cuprian Tourmaline when I first saw it because I had never heard of it. I came across these which I found very interesting:-

http://atggems.blogspot.com/2008/11/paraiba-lawsuit-dismissed.html

http://gemwiseblogspotcom.blogspot.com/2006/07/cuprian-tourmaline-from-mozambique.html

Probably doesn't help to answer your question and I see Meeshoo who knows a million miles more than me has posted but you may think these are worth a read.

Klosblue
07-12-2008, 07:32 PM
There's a very fine line between what you might class as Paraiba and what you wouldn't. Being neon and vivid/intense are different.

Look at these two links. The first is all Paraiba - you can see the colour and "neon-ness" screaming at you. The second link is blue/green tourmalines. Some are incredibly vivid but none have the neon quality although are stunning and incredibly vivid.

http://www.paraibainternational.com/products.php?category=3&page=all&sort=
Look at product code id 1426 - for me that doesn't cut the mustard!

http://www.paraibainternational.com/products.php?category=7&page=all&sort=
Look at product code id 537 - I bet you lots of places would class that as Paraiba.


That's really interesting Meeshoo. I've seen a lot of stones which look identical to those on Page 2 being sold as "Paraiba"!! Not good!

Sacha
07-12-2008, 09:23 PM
There's a very fine line between what you might class as Paraiba and what you wouldn't. Being neon and vivid/intense are different.

Look at these two links. The first is all Paraiba - you can see the colour and "neon-ness" screaming at you. The second link is blue/green tourmalines. Some are incredibly vivid but none have the neon quality although are stunning and incredibly vivid.

http://www.paraibainternational.com/products.php?category=3&page=all&sort=
Look at product code id 1426 - for me that doesn't cut the mustard!

http://www.paraibainternational.com/products.php?category=7&page=all&sort=
Look at product code id 537 - I bet you lots of places would class that as Paraiba.

Bit of a botched job with the cutting on that one!

I personally wouldn't mind (assuming I had a spare $15k+ the one nearby numbered 2192, t'would be a tad big for a ring,
but perfect for a pendant!

Thanks for the links ladies, all makes interesting reading. I would think folks who got their hands on the original Brazilian Paraiba Tourmaline would be most happy now. I know Gems sold some, indeed I managed to acquire a very very small piece that must have been lurking in the vaults long after the rest was sold. But can anyone, who was an earlier customer than myself, tell us what sort of quantities they had for sale?

I well remember the video clip of Gavin sitting in his office describing to us the scale of colours of PT. But most of the pieces I see these days, that are not 'considered' prices, are very watery and pale in colour as well as being windowed. Quite disappointing.

Gemstone Gav
08-12-2008, 12:40 PM
Hi Guys:

Thanks for the question Miss Magpie.

Tourmaline is a group of related minerals whose differences in composition result in a plethora of colours. While there are thirteen different mineralogical varieties of Tourmaline, you only really need to worry about Elbaite. Named after the island of its discovery (Elba) in Tuscany, Italy, Elbaite is the backbone of Tourmaline gemstones. The only commercial exception is the exceedingly rare Chrome Tourmaline, a vivid pure green East African Dravite coloured by chromium and vanadium. However, unless an Elbaite Tourmaline contains trace amounts of copper it cannot be called Cuprian Elbaite Tourmaline.

In 2006, the LMHC (Laboratory Manual Harmonisation Committee) decided that because 'Paraíba' from Brazil and Africa is indistinguishable using standard gemmological tests, blue (electric blue, neon blue or violet blue), bluish-green to greenish-blue or green copper-rich (Cuprian) Elbaite Tourmaline with a medium to high saturation and tone of any origin can be called ‘Paraíba’. In his book, ‘Gemstones: Quality and Value, Volume 1’, Yasukazu Suwa says, “The appeal of Paraíba Tourmaline far exceeds that of other gems, to the point where they are desired even by people who are accustomed to seeing a variety of gemstones”. The main reason for this is its vivid colours, characterised by a sizzling, electric, neon or fluorescent appearance as well as a distinctive transparency that affords Paraíba Tourmaline’s fine brilliance. In a way, colour in Paraíba Tourmaline is perhaps a dichotomy, in that its typically medium toned, sometimes almost pastel hues, still have intensity. This is unusual and a big reason for its appeal.

Curprian Tourmaline is the name for the copper-rich (Cuprian) Mozambique Tourmalines that do not fall within the acceptable colours for Paraíba Tourmaline. Extremely collectable for the true Tourmaline connoisseur, Curprian Tourmaline is a fairly new gemstone, only appearing commercially since the discovery of Paraíba Tourmaline’s Mozambique deposits. The colours seen in Curprian Tourmaline include burnt oranges, dusty roses, lavenders, purples, reddish-purples, and yellows. According to current industry standards, Product ID: 2509 and Product ID: 2504 on this page http://www.paraibainternational.com/products.php?category=3&page=all&sort= are not the correct colour (i.e. they're purple) to be called Paraíba Tourmaline. I would call them Curprian Tourmaline.

Guys, please don’t get confused over ‘neon-ness’. This characteristic is a by product of its copper content, not the defining criteria. As long as it’s got the copper, the right colour range (variously described as Caribbean blue, peacock, copper-green, neon-aquamarine, swimming pool blue or turquoise blue, from a gemmological perspective, the colours range from bluish-green, blue-green, greenish-blue, blue and bluish-violet) and a medium to high saturation and tone (which is perhaps somewhat subjective for some), it is Paraíba Tourmaline. For example, some of the gems on this page http://www.paraibainternational.com/products.php?category=7&page=all&sort= come close in terms of colour and ‘neon-ness’, but I assume they don’t have copper, so they cannot be sold as Paraíba Tourmaline.

I hope this helps and as always, please let me know if I can be of any further assistance.

Kind Regards,

Gav

MissMagpie
08-12-2008, 02:10 PM
Thanks, Gav!