Another Alexandrite question

[Kashmir]

I am in possession of an Alexandrite purchased by my grandfather in Singapore sometime in the early part of the 20th century. My grandparents did not know the meaning of the word frugal nor do I believe my grandfather would have knowingly purchased a synthetic stone but anything is possible. I do know my grandmother once dove under a bed to retrieve the stone after it popped out of the setting. Did I fail to mention this occurred during an air raid on Hong Kong during the Second World War? I just don''t know if she would have done so were the stone a synthetic.

It is a substantial stone, almost as big around as a dime. Could it be real? Were there synthetic stones around at the time when it was purchased? I will post pictures should anybody be interested.

I appreciate any help with this.

 

[ma re]

From what I know, alexandrite (unlike many other gems) wasn''t synthesized until the 1970''s, so if you''re sure that it''s an alexandrite, you can be pretty certain that it''s a natural stone. But it can (theoretically) be a lot of other things, so make sure you have it checked by a gemologist.

 

[chrono]

It could also be a colour change garnet as well which has the same colour change. If it is really a natural Alex, it is worth a fortune. I’d suggest getting the stone verified by an experienced coloured gemstone appraiser or sent for lab certification, and INSURED!

 

[Barrett]

yea..I agree I don''t think they had syn. alex''s back then...how good a color change does it do?

 

[T L]

Synthetic color change corundum has been around since many of our grandparent's times, and was used as a substitute for alexandrite. The color change is often red/pink to purple. What is the color change on this stone?

The only way to know for sure is to take it to a gemologist, but a photo of the stone would also be helpful if you could post one.

 

[LD]

TL is spot on. Unfortunately a huge amount of "antique" jewellery containing Alex is actually a colour change corundum. If it's as big as a dime (which I think is about .5"?) then you're talking about 4-5 carats. If that's the case and it is an Alex, if the colour change is good, then it would be worth a small fortune. You really need to get this checked out BUT go in thinking it's synthetic and that way, anything else is a bonus.

Some things to check in the meantime:-

1. Can you see any inclusions? If so, what do they look like?
2. What is the daytime colour?
3. What is the colour under electric light in the evening?
4. Does the whole gemstone change colour or just parts?

It may be synthetic if:-

1. The gemstone is clear with no inclusions. Typically with a loupe you will see something in an Alex. They are very rarely completely clean in a gemstone of that size.
2. The whole gemstone changes colour and changes colour dramatically - again, for an Alex that size, to see an incredible 100% colour change is rare. Not impossible but very rare.
3. The colour should be typically a green colour during the day and turns to a purple (almost grape red colour) at night. If the colour is reversed or any other colour variation then it could be a synthetic.

You may find this interesting:

http://www.alexandrite.net/chapters/chapter7/index.html

 

[Kashmir]

The color goes from teal when exposed to indirect sunlight to deep purple in the sun to a red-purple color under incandescent lights. Lousy picture but this is the stone in direct sunlight.

 

[Kashmir]

This is the stone outside in indirect sunlight. Again, apologies for the picture quality. The color is teal or there abouts. It will also turn a reddish purple raspberry-esqe color. Anybody know of a colored gemstone person in the Southern USA?

 

[jstarfireb]

Really hard to tell from the pics - sorry! Hopefully you can find an appraiser and get back to us; I''d really love to hear how this turns out.

 

[Kashmir]

I promise to let everybody here know the outcome of this.

I really thank you for all the input.

 

[chrono]

Sounds like you are having a GG look at it? There''s just no way to ID the stone from a few pictures but thanks for them anyway.

 

[Kashmir]

Oh, I realize the stone couldn''t be authenticated via the internet. A couple of people had asked for pictures so I posted a couple. They are poor, I admit.

Again, I thank all of you for your input.

 

[LD]

I've hesitated posting up but I hope you don't mind me being honest? The colour change you describe i.e. looking teal in indirect sunlight and purple in sunlight indicates it's not Alexandrite. Alex will NOT go purple in sunlight. If anything it should look at its most green. It's only under electric light that it should turn purple. I'm sorry and I hope you don't mind me saying that?

 

[chrono]

LD
You are correct about purple indoors and green outdoors but I do have a question about the teal colour: do you think it's bleeding of colour (incomplete change)?

ETA
I reread that the poster wrote it is purple outdoors - that's definitely not an Alex colour. It sounds the opposite of what an Alex does.

 

[LD]

Date: 7/10/2009 1:43:54 PM
Author: Chrono
LD
You are correct about purple indoors and green outdoors but I do have a question about the teal colour: do you think it''s bleeding of colour (incomplete change)?

ETA
I reread that the poster wrote it is purple outdoors - that''s definitely not an Alex colour. It sounds the opposite of what an Alex does.

And very typical of a synthetic/different gemstone unfortunately. That''s why I specifically asked about the colour change in my first post. It can be fairly definitive in terms of diagnosis if the colour change is "wrong".

Chrono, some Alex do have a teal daytime colour - not a true teal as we know it but certainly a blue/green rather than a forest green. I''ve seen this in the Brazilian stones although I believe some of the Indian stones display this also (although personally I haven''t found that with the Indian material).

 

[Kashmir]

I don''t mind anybody saying anything unless it is to call me names or something. It''s all cool.

I still plan on having the stone authenticated but I am planning on a ''not an Alexandrite'' outcome.

Thanks all.

 

[LD]

You know what? The thing that''s most important is that this is a family heirloom and you have lovely memories associated with the ring. So it doesn''t matter if it''s glass or the most expensive gemstone in the world because it''s unique to you and your family. Enjoy your ring. x

 

[Richard M.]

Kashmir,

A simple check of refractive index should establish whether the gem is corundum or chrysoberyl (alex). Unless you view color change under rather strict lighting conditions it''s not definitive: even geniune alex''s can display inconclusive colors when natural daylight is mixed with fluorescent or incandescent. Many jewelers are able to make the simple test and it will put you on track for a positive ID.

Richard M.

 

[LD]

Richard

The poster said she was seeing purple outdoors in sunlight. I have never seen an Alex do this. I agree if there were a mix of incandescent lighting it could be possible but that''s not what the poster said. Have you observed an Alex change to the incandescent light colour outside in sunlight please? I''d be very interested if you have.

Thanks you any information you can give.

 

[diamondringlover]

I hope it is Alexandrite, that would be sweet, I know my Alex does the opposite, mine goes teal in sunlight and purple in indoor lighting.

 

[Richard Sherwood]

Sounds like (and despite the blurry photos, looks like) synthetic color change sapphire.

 

[T L]

Date: 7/11/2009 7:15:36 PM
Author: diamondrnglover
I hope it is Alexandrite, that would be sweet, I know my Alex does the opposite, mine goes teal in sunlight and purple in indoor lighting.

Mine as well.

 

[LD]

Date: 7/11/2009 7:15:36 PM
Author: diamondrnglover
I hope it is Alexandrite, that would be sweet, I know my Alex does the opposite, mine goes teal in sunlight and purple in indoor lighting.

That''s the normal colourway for an Alex, although the daylight colour is usually more of a forest green or a shade of green rather than blue/green (although there are some that display the teal colour). HOWEVER, the colours you describe can also be the "normal" colourway for a colour change sapphire, colour change garnet etc., and a number of others (including synthetic Alex). Sooooooooo, if you see this colourway it''s not definitive and you need to get the stone checked out.

 

[norman_in_L.A.]

Hi Kashmir:

Have you taken the stone to a Gemologist?

I looked at your photos and I agree with Richard that it looks like a synthetic color change sapphire. We see this stone type once or twice a week. Most people cannot believe that synthetics were being created in the lab a hundred years ago.

A quick check @ 10X power will reveal curved striae.

 

[Sagebrush]

As Richard says, I think you are looking at a Synthetic sapphire. Sapphire was first synthesized around 1890 and literally piles of the color shift type was sold in Mexico, Egypt and other places as alexandrite.

They do shift color, so that fools many people enough, at least, to buy. I have never heard of one that changes color from purple-red to green as true alexandite does. They tend to have more of an amethyst like color that adds red, but change the chemistry a bit and voila!