color change spinel ?

[colormyworld]

This is a picture of a spinel from Vietnam that I bought as a blue spinel. In natural light it is very blue but in incandesecent light it is a slightly reddish purple color though. Any experts or for that matter anybody care to share thier thoughts as to whether this would be considered a CC stone? The photo was taken using an OTT light for the fluorescent and a GE reveal bulb for the incandescent light. The colors are very true to what I see IRL.

 

[chrono]

CMW,
This colour shifter looks and behaves very much like the other 4 ct Vietnamese spinel I memo-ed a few months ago. This had a mix of purple and blue at the same time. It was considered a CC spinel and showed a gorgeous cornflower sapphire blue under strong sunlight, mixture of the 2 in regular sunlight and a grape-ish purple in other lights. So, yes, in my limited knowledge, I would consider this a CC spinel.

 

[colormyworld]

Hi Chrono, Thanks for the reply. In direct sunlight this stone shows a pretty strong red flash along with the blue . It does not really show any purple in the body color of the stone though. Although the camera does pick some up I can not see it with my eye.

I took a couple of more pics to better show the color shift/ change.

 

[colormyworld]

And the blue. In the first picture I am getting a little blue from a fluorescent light in the background.

 

[chrono]

It sounds very pretty. I'm looking forward to more pictures.

ETA
Woah! That's quite a strong change. I'd consider that a CC/shifter for sure.
Say CMW, you sure that CC spinel isn't up for sale?

Lovely stone.

 

[Pandora II]

Okay, I was waiting for more photos..

I wasn''t sure with the first one if it was just anomalous or pseudo-dichroism.

However that looks like a true colour shift/cc to me.

Lovely piece!

Explanation for those who want the detail - stones like spinel and garnet are singly refractive and therefore theoretically cannot show dichroism (where a stone shows two colours at the same time due to the light rays being split into two beams of different wavelengths).

However, they can show anomalous or pseudo-dichroism - IIRC this is due to the way light is absorbed by certain stones.

Worth remembering, as lack of double refraction is normally used as a good way of separating spinel and garnet from other doubly refractive stones (tourmaline, corundum etc)

 

[cushioncutnut]

Pandora... thanks for the information... (not that I will remember that..LOL!) but it is a great explanation.

CMW... as always, you have the most fabulous stones. In each picture, it definately takes on a different color to my eyes. The first picture reminds me a tiny bit of my color change spinel............. I struggle to say that because I know IRL your CC spinel would blow my CC spinel out of the water!!

 

[T L]

Spinels are one of my least favorite gems, and that''s probably because I''ve never seen one in person or in photos that I absoutely adored. However your threads are really making me drool!! Very nice stuff!!

 

[colormyworld]

Thank you Chrono,Pandora, R, TL. In the first picture I used a fluorescent and incandescent light to show both colors at once. Although I have no lab report I suspect this stone contains cobalt because of strong red flashes from pin point light sources.

Tourmaline lover I can''t really blame you for thinking spinels are not worthy of much effort because you have never seen one that impressed you. Good ones are extremely tough to locate and when found are even harder to seperate from the owner. Please believe me when I say that they are worth the effort though.

 

[Harriet]

Date: 12/23/2008 10:31:35 AM
Author: tourmaline_lover
Spinels are one of my least favorite gems, and that''s probably because I''ve never seen one in person or in photos that I absoutely adored. However your threads are really making me drool!! Very nice stuff!!

There are quite a number of icky ones out there. I hope you get to see one that changes your mind!

 

[T L]

Date: 12/23/2008 9:11:52 PM
Author: Harriet

Date: 12/23/2008 10:31:35 AM
Author: tourmaline_lover
Spinels are one of my least favorite gems, and that's probably because I've never seen one in person or in photos that I absoutely adored. However your threads are really making me drool!! Very nice stuff!!

There are quite a number of icky ones out there. I hope you get to see one that changes your mind!

Ha! I might have to go to the Tower of London to see one in the crown jewels just to see one that impresses me. The good ones are so hard to come by.

 

[Harriet]

No kidding. That''s why I''m going to pay CMW a visit.

 

[cushioncutnut]

Date: 12/23/2008 9:53:39 PM
Author: Harriet
No kidding. That''s why I''m going to pay CMW a visit.

LOL! That is what I was thinking!!!! Mrs. CMW is one lucky lady!!!!

 

[bling addict]

Well I really don''t know anything much about gems.....but love the colours of your spinel!

 

[Kelli]

WOW that''s soooo pretty! I have no idea what makes something qualify as a "color change" stone, but there certainly are different colors in the pics!

 

[coatimundi_org]

Awesome spinel!

Looks like true cc with nice hues to boot!

 

[marcy]

Very pretty!