Show me your copper bearing tourmaline!

[T L]

Paraiba ****!!!

So many AWESOME stones - you drive me crazy!!!!!!!

TL - the round!!!!!

Minousbijoux - the last cushion-oval!!!!!

I have only some small brazilian and two purple mozambique stones.

The round isn't glowy though. Can you believe that was the worst cut stone in the universe. It was like I cut it blindfolded with one hand tied behind my back and with a saw. It was the ugliest cut ever (the lapidary said so too), but it did glow more before the recut. It lost saturation due to the recut even though less than a carat was removed. It is still a very pretty stone, but looks like a regular open blue tourmaline than a glowy paraiba.

I have this oval, which is poorly cut and inluded, but look at that glow. My mint garnet, all the way to the right, reminds me of a green paraiba. The blue ones just glow madly though.

 

[T L]

I have repeatedly found that the violet is not nearly as attractive nor nearly as glowy and neon as when it is heated and turns blue...perhaps I've been looking at all the wrong violets!

There are also purple copper bearing stones. This is mine, has a GIT memo stating its copper bearing, but to me, it reminds me of an amethyst. I'm not too enamored with it, but I just took a pic anyways.

 

[Marlow]

Marlow, don't feel too bad. I remember Steve Perry telling me a story of a time back in the 1990's when he was in Brazil not too long after the Batalha mine find, and stones were making it out into the local market. He was negotiating for a fairly good size parcel of cuprian tourmalines from the Batalha mine (all faceted) to purchase. He came to an agreeable price, left for minutes to procure the cash, but by the time he came back, another person purchased the entire lot (a German I believe is what Steve told me, anyone you know?).

Poor Mr. Perry!!!

Most Paraiba was sold to german cutting factories - family buiness like Wild, Petsch, Haag, Ruppenthal and Zang.

Thats why we still get the smaller stone "quite" cheap - they have a large stock ( same with spessartin, Mozpa ...).

For Acinom or other european PSer f. e. it would it be interessting to visit Inhorgenta - unfortunately you need some connections, it is a non public show...

Groh and Ripp for example offered hundreds of fine stones ( Paraiba, Mahenge..) - 1-10 ct whatever you what....a nightmare!!!

 

[RSargent]

Wow. I LOVE this stone. I think tourmaline's pleochroism and bifringence is what grabs me. Stunning.

 

[minousbijoux]

Wow. I LOVE this stone. I think tourmaline's pleochroism and bifringence is what grabs me. Stunning.

How so?

 

[RSargent]

When I turn these stones they seem to bleed into different shades of color.

 

[chrono]

Good point - my blue green tourmaline shows pleochroism easily but my turquoise blue cuprian doesn't seem to do this, IIRC.

 

[RSargent]

Do you think heating has anything to do with that? The unheated cuprians I've seen are pleochroic but not when they are that cyan blue color....

 

[RSargent]

TL, your violet cuprian reminds me of my favorite lilac flowers just as they begin to open in May...bluish purple with hints of pink. That's what I meant when I spoke of pleochroism.

 

[chrono]

That's not the traditional definition of pleochroism. Pleochrosim is when the stone appears to be different colours when observed at different angles (a axis versus b axis).

 

[Marlow]

Correct Chrono!

And tourmaline is dichroitic - I love to be a smart a??

Sorry but a and b-axis are similar in trigonal, hexagonal and tetragonal system

So it is c-axis and a/b axis

------

In triklin, orthorhombic and monoklin system ( chrysoberyl / orthorhombic) a, b and c axis are different( length and angle) so we have
3 colors - Alexandrite for example...

 

[RSargent]

I have much to learn but enjoying the whole process.

 

[chrono]

Correct Chrono!
And tourmaline is dichroitic - I love to be a smart a??

Sorry but a and b-axis are similar in trigonal, hexagonal and tetragonal system

So it is c-axis and a/b axis

------

In triklin, orthorhombic and monoklin system ( chrysoberyl / orthorhombic) a, b and c axis are different( length and angle) so we have
3 colors - Alexandrite for example...

My mistake - yes, it should be a/b versus c axis for tourmaline!
And yes, tourmaline is dichroic, Mr. Smart Alec.

 

[Marlow]

Chrono, I am sure it was only a test!!

 

[minousbijoux]

Correct Chrono!

And tourmaline is dichroitic - I love to be a smart a??

Sorry but a and b-axis are similar in trigonal, hexagonal and tetragonal system

So it is c-axis and a/b axis

------

In triklin, orthorhombic and monoklin system ( chrysoberyl / orthorhombic) a, b and c axis are different( length and angle) so we have
3 colors - Alexandrite for example...

This is why I was asking - except for the c axis, I don't think my tourmalines change or bleed shades of color as I turn them (unless they have big windows and the outer edge is more saturated than the middle!) I also don't think of tourmaline as a stone with high birefringence - not like some zircon say, or sphene.

But I'm glad you said something, RSargent, because you got me to thinking.

 

[Marlow]

You use a dichroscope??.

I see only a weak dichroism but my stones are very small ( Turquoise, neon blue, green and turquoise-purple bicolor)

 

[Arcadian]

Correct Chrono!

And tourmaline is dichroitic - I love to be a smart a??

Sorry but a and b-axis are similar in trigonal, hexagonal and tetragonal system

So it is c-axis and a/b axis

------

In triklin, orthorhombic and monoklin system ( chrysoberyl / orthorhombic) a, b and c axis are different( length and angle) so we have
3 colors - Alexandrite for example...

This is why I was asking - except for the c axis, I don't think my tourmalines change or bleed shades of color as I turn them (unless they have big windows and the outer edge is more saturated than the middle!) I also don't think of tourmaline as a stone with high birefringence - not like some zircon say, or sphene.

But I'm glad you said something, RSargent, because you got me to thinking.

Thats interesting! some of my non-cuprian tourmalines you can see several colors depending on how they're oriented, especially the last one I set. Most if not all the tourmalines I have set at current were precision cut, no window to be had. I have to take the princess for walk but I'm also really interested in this discussion!

My violet has a huge honking window, I don't really get anything other than violet/blueish out of it

 

[minousbijoux]

But Arc, are you talking about the c axis? Because that would explain it - you will see another color there...

 

[Arcadian]

But Arc, are you talking about the c axis? Because that would explain it - you will see another color there...

Yes...I think? A/B axis is the flat part of the uncut stone right? C axis is the length (at least I always thought it was) This is where my knowledge gets a bit dicey. Go easy I need about 3rd grade level science to understand (if someone wants to provide a picture even better!)

 

[Marlow]

For example BERYLL

Aquamarine - often long hexagonal prism but Morganite - flat tabular hexagonal prism ( c-axis could be shorter then the diameter of prism)

This is called HABITUS

Same in corundum - some "flat" rubies but also some loong dipyramid sapphire...

 

[RSargent]

Wow.I now question my brain. Its like if the dress is blue or white. I have collected tourmalines since I was a little girl with my dad. I have never seen stones with so much motion in color. As I turn them and view them in different light sources they blend into subtle colors that bleed into each other...mesmerizing. The Mozambique cuprians are even better. Wow. Maybe it's dichroism? Help me here my gemologist friends. The turquoise blues I have that are cuprians are immune to this but not the green blues. Look at TLs violet. Does anyone else see all the colors in that one photo? I am 52 and not a drinker. I promise!

 

[pregcurious]

Learning here also. I have no tourmalines. Perhaps I should fix that.

 

[minousbijoux]

Learning here also. I have no tourmalines. Perhaps I should fix that.

This is a problem. Of all people! Thank God you see the solution.

 

[T L]

Some tourmalines show birefringence, which causes light to break up into other colors when hitting the facets. I have a few pink tourmalines like this, where some violet is shown.

I don't remember if my violet tourmaline does this, because it sits at the bank 99% of the time. I have yet to set it.

Some tourmaline is also pleochroic, meaning that one axis shows another hue/tone than another axis. Iolite and andalusite are examples of gems with strong pleochroism.

 

[lilmosun]

The cuprian that brought me to PS doesn't have light bulb glow but definitely has flashes of blue popping out of the green in daylight (camera doesn't seem to pick it up though).



Picked this cuprian cut by Barry up from a friend selling on LT



And my baby Paraiba ring shown in my avatar (which got me hooked)

Totally missed the train but happy/lucky to find some pretties in my budget (as I tell myself as I look at the treasures others have in envy).

 

[Siameseroo]

Beautiful tourmalines! I love the windex blues but am more drawn to the blue green cuprians. Here is to hoping I can afford one one day!

ETA: lilmosun - beautiful tourmalines! i love the bluish green tones.

 

[lilmosun]

Thanks ricezo...I would love a larger windex blue but the closest I'll probably ever get is an apatite. You probably can still find an occasional deal on blue-green cuprians (Paraiba-type) with some effort and patience. I bought both of mine in the past year. (And yes, pregcurious needs some tourmalines!)

 

[kgizo]

Was out shopping for watches for the husband today and saw this beauty. JB Star 3+ Carat paraiba, paraibas also on the shank. They wanted $99,000.

 

[minousbijoux]

Was out shopping for watches for the husband today and saw this beauty. JB Star 3+ Carat paraiba, paraibas also on the shank. They wanted $99,000.

Um, yes please!

 

[Acinom]

Was out shopping for watches for the husband today and saw this beauty. JB Star 3+ Carat paraiba, paraibas also on the shank. They wanted $99,000.

Ah, I could live with that
Thanks for sharing!