Alexandrites

[Phantasmagoria]

I know there is a topic section somewhat like this ones, but it is not quite about my question. The other topic asked what the difference was between Alexandrites and the other simular color-changing stones.

My question is, If one baught a stone they believed to be Alexandrite, how could he/she tell if it really is an Alexandrite, or just a color-changing sapphire? If it helps, here is a picture of the exact stone i am curious about.

Alexandrite in queston.

 

[Barbara]

Date: 8/5/2006 8:10:18 AM
Author:Phantasmagoria
I know there is a topic section somewhat like this ones, but it is not quite about my question. The other topic asked what the difference was between Alexandrites and the other simular color-changing stones.


My question is, If one baught a stone they believed to be Alexandrite, how could he/she tell if it really is an Alexandrite, or just a color-changing sapphire? If it helps, here is a picture of the exact stone i am curious about.


Alexandrite in queston.

Hi Phantasmagoria,

Alexandrites from various locations and with different amounts of trace elements responsible for the color change, show some variation in their daylight and incandescent light colors, but most are some shade of teal and raspberry. I have not seen any with the dramatic spectral green and vivid orange color change of this stone. Neither does that photo look like the typical cc sapphires which tend to be more of a purplish blue to reddish purple color change. I have seen both color change garnet and man-made color change glass with similar shades to those in your photo.

It is never possible to "sight ID" a stone -- gems must be tested, so please take my above remarks with a grain of salt and keep in my that I am no, by no means, an Alex expert. However, I can say with some certainty that simple gemological tests would determine almost immediately whether the stone is Alex or not. (Refractive index for example, in this case should be telling). If the stone is Alex, it would be more difficult to determine (but usually possible) whether it is of natural or man-made origin, and whether it has been enhanced or not.

Barbara

 

[Richard Sherwood]

Alexandrite is tough to photograph, especially under incandescent lighting. The digital camera (mine at least) never seems to portray the actual color seen with the eye.

This stone has the look of natural alexandrites I have photographed. As Barbara points out the easiest solution to your problem is a simple refractive index test, along with examination by a competent gemologist to determine natural versus synthetic.

I notice the stone is offered by Thai Gems. Out of an appraiser''s curiosity, do you mind if I ask the carat weight, and how much they''re asking for the stone? Did they mention a country of origin?

 

[Richard M.]

Date: 8/5/2006 11:52:20 AM
Author: Barbara
If the stone is Alex, it would be more difficult to determine (but usually possible) whether it is of natural or man-made origin, and whether it has been enhanced or not.

Just curious Barbara: I''ve not heard of any enhancements to alex, nor are any listed in my AGTA sheet. Am I behind the curve? I know of attempts to irradiate Indian cat''s-eye to change the color but that''s the only chrysoberyl treatment I''ve heard of.

Richard M.

 

[Barbara]

Richard,

My comments on the relative ease of determining the species of a gem compared to figuring out whether it is synthetic or treated were meant generally. I know of no current enhancement process being used specifically on Alex.

It''s kind of like being on a treadmill whose speed is ever increasing, in gemology these days, though. You keep having to work harder just to stay in place! It sounds like you are running as fast as I am. Your gallery is magnifcent, by the way. I particularly like the uvarovite piece.

Barbara

 

[Richard M.]

Date: 8/5/2006 1:22:58 PM
Author: Barbara
It''s kind of like being on a treadmill whose speed is ever increasing, in gemology these days, though. You keep having to work harder just to stay in place! It sounds like you are running as fast as I am. Your gallery is magnifcent, by the way. I particularly like the uvarovite piece.

Thanks for clarifying. Yes, all the new treatments are great for the labs but I''m not so sure they''re good for the gem business. I''m having very mixed feelings about the whole process. Thanks for your comments on the Gallery. Uvarovite is a favorite: just wish it grew single crystals large enough to cut center stones.

Richard M.

 

[nicky newark]

Date: 8/5/2006 12:15:53 PM
Author: Richard Sherwood
Alexandrite is tough to photograph, especially under incandescent lighting. The digital camera (mine at least) never seems to portray the actual color seen with the eye.

This stone has the look of natural alexandrites I have photographed. As Barbara points out the easiest solution to your problem is a simple refractive index test, along with examination by a competent gemologist to determine natural versus synthetic.

I notice the stone is offered by Thai Gems. Out of an appraiser''s curiosity, do you mind if I ask the carat weight, and how much they''re asking for the stone? Did they mention a country of origin?

I would stay far away from anything at Thai Gems. You will be disappointed by their quality for sure.

 

[Phantasmagoria]

Quantity: 1 Piece(s)
Approx Weight: 0.47 Ct.
Product Type: Alexandrite
Shape: Oval Cut
Size: 6 x 4 MM.
Color: Change Green To Purple Red
Clarity: Slight Inclusion
Origin: India
Hardness: 8.5
Specific Gravity: 3.71-3.74
Refractive Index: 1.745-1.757
Chemical Composition: Beal2o4
Orthorhombic
Treatment: None
Recommended
Retail Price: $1,468.00

I don''t know if that helps you, richard. It was an auction on e-bay. It may be poor quality but i''m not picky, i''m am only a poor college student that found out about alexandrites and was interested in having one. I don''t really mind if it isn''t naturally made, though here they say it is. As long as it IS an alex i''m happy.
Thank you all for helping me out with my question, and i hope to learn more about this wonderful gem.

 

[colorchange]

Date: 8/5/2006 12:15:53 PM
Author: Richard Sherwood
Alexandrite is tough to photograph, especially under incandescent lighting. The digital camera (mine at least) never seems to portray the actual color seen with the eye.

This stone has the look of natural alexandrites I have photographed. As Barbara points out the easiest solution to your problem is a simple refractive index test, along with examination by a competent gemologist to determine natural versus synthetic.

I notice the stone is offered by Thai Gems. Out of an appraiser''s curiosity, do you mind if I ask the carat weight, and how much they''re asking for the stone? Did they mention a country of origin?

Richard, you are mentionning country of origin.
I''m not dealing in alex but hear that those from Russia are worth more... is there any way of checking the origin ?

 

[Phantasmagoria]

Well it says it is from India. I actually recieved the stone today and it looks absolutely nothing like the photo. Rather than turning green to that odd, orangish color, it turns Bright, gorgeous green to a gray-purple. I am not saying i am disappointed, i see it is a really low quality alex, but at least it IS an alex and i like it. Also for how much i paid for it i shouldn''t complain

i wasthinking of returning it, however, just because it was so different from the picture and that made me mad, but i asked my boyfriend and he said "then get a different kind of stone" and immediately i was thinking emerald of some sort, but realized the alex looks like one anyways in the sunlight lol.

thank you all for your help!

 

[oshinbreez]

I also bought one of the Alexandrites from Thai Gems. Here''s the auction:




Quantity: 1 Piece(s)
Approx Weight: 1.77 Ct.
Product Type: Alexandrite Cats Eye
Shape: Round Cab Cabochon
Size: 7.3 MM.
Color: Change Green To Purple Red
Clarity: Slight Inclusion
Origin: India
Hardness: 8.5
Specific Gravity: 3.71-3.74
Refractive Index: 1.745-1.757
Chemical Composition: Beal2o4
Orthorhombic
Treatment: None
Recommended
Retail Price: $1,656.00

Is this gemstone real or synthetic?
All our items are natural/real unless clearly described as ''Created Gem''.


I got it for REAL cheap, so I won''t complain either. I took some pics of it today.

First was in direct sunlight.

 

[oshinbreez]

Next in the shade

 

[oshinbreez]

Last under florenscent light. All 3 pics were taken on a piece of white computer paper.

 

[Phantasmagoria]

well yours seems to have quite a bit of color change that''s good. Mine doesn''t change in color very much, however, and was nothing like how it was pictured

 

[oshinbreez]

I''m not too sure about there being much color change. I think it was the camera. Notice how none of the backgrounds are white? And they were all taken on a white piece of paper. Atleast they are "Natural"

 

[Richard M.]

All,

I’ve been building up to this little rant for a long while so I hope no one on the thread takes it personally. Briefly stated: genuine alexandrites with top color change are expensive. It would be a miracle to find such a stone at a low-priced auction site like EBay or from a mass Etailer like Thaigem.

Here’s a Reality Check. If you go to a site like THIS ONE you will be presented with an image of a top quality alexandrite, usually of fairly large size. Books and other internet sites usually show only top-of-the-line alex''s. Stones like that are rare and for perspective, below is an idea of current retail pricing of one carat+ stones. (Bear in mind sellers'' mark-ups vary and the prices shown here may be high for some dealers, low for others. They are examples only but are based on pricing data widely accepted in the gem trade.)

Lowest commercial quality: $400 to $1,600 per ct. Good quality: $1,600 to $6,000 per ct. Fine quality: $6,000 to $11,000 per ct. Extra Fine quality: $11,000 to $15,000 per ct. Remember: these price ranges are for stones from 1 to 2 carats. Stones from 2 to 3 carats command significantly higher per carat prices, and gems from 3 to 5 carats are very rare and much higher yet.

Prices are strongly affected by specific daylight and incandescent colors as well as the strength and percentage of change. Some sellers'' prices show a preference for the types color change from one location or another: some claim Brazilian is better than Russian and vice-versa. Indian stones in general (there are major exceptions) don''t display the strong nighttime red colors of the foregoing types but usually have a very nice daylight hue as Phantasmagoria discovered.

Alexandrite (chrysoberyl) is rated as a Type II stone by GIA, defined as usually eye clean with some inclusions under magnification. Clarity can vary by mining location. Brazilian alex is often very clean compared with Russian, Indian or African stones.

While alex from Tanzania and Madagascar may be very fine, those locations are known for producing color changes that differ from the traditional reddish-to-greenish of alexandrite. Only stones showing red-to-green change are graded as alexandrite. Non-red/green colors are graded as color-change chrysoberyl and bring lower prices.

No alexandrite treatments are presently known. The quality of cutting can affect alex pricing but if clarity, colors/color change and size are high-end, cut usually plays a minor role in valuation.

I probably haven''t covered all the bases but it just isn''t realistic to expect top colors and color change from low-priced stones. They are affordable natural stone choices for those with June birthdays or consumers who just want a genuine alexandrite.

Richard M.

 

[nicky newark]

Date: 8/7/2006 3:49:20 PM
Author: Phantasmagoria
Well it says it is from India. I actually recieved the stone today and it looks absolutely nothing like the photo. Rather than turning green to that odd, orangish color, it turns Bright, gorgeous green to a gray-purple. I am not saying i am disappointed, i see it is a really low quality alex, but at least it IS an alex and i like it. Also for how much i paid for it i shouldn''t complain

i wasthinking of returning it, however, just because it was so different from the picture and that made me mad, but i asked my boyfriend and he said ''then get a different kind of stone'' and immediately i was thinking emerald of some sort, but realized the alex looks like one anyways in the sunlight lol.

thank you all for your help!

If you buy Emerald, Alexandrite or anything else from Thai Gems you will always be disappointed. They misrepresent everything and nothing is going to look like their images.

 

[oshinbreez]

ou buy Emerald, Alexandrite or anything else from Thai Gems you will always be disappointed. They misrepresent everything and nothing is going to look like their images.

In all fairness, I have bought some stones from them that are very pretty and they were represented accurately. Others weren''t the greatest. But, I don''t get my hopes up too high. I''ll believe it when I see it.

 

[movie zombie]

Date: 8/7/2006 7:49:03 PM
Author: Richard M.
All,

I’ve been building up to this little rant for a long while so I hope no one on the thread takes it personally. Briefly stated: genuine alexandrites with top color change are expensive. It would be a miracle to find such a stone at a low-priced auction site like EBay or from a mass Etailer like Thaigem.

Here’s a Reality Check. If you go to a site like THIS ONE you will be presented with an image of a top quality alexandrite, usually of fairly large size. Books and other internet sites usually show only top-of-the-line alex''s. Stones like that are rare and for perspective, below is an idea of current retail pricing of one carat+ stones. (Bear in mind sellers'' mark-ups vary and the prices shown here may be high for some dealers, low for others. They are examples only but are based on pricing data widely accepted in the gem trade.)

Lowest commercial quality: $400 to $1,600 per ct. Good quality: $1,600 to $6,000 per ct. Fine quality: $6,000 to $11,000 per ct. Extra Fine quality: $11,000 to $15,000 per ct. Remember: these price ranges are for stones from 1 to 2 carats. Stones from 2 to 3 carats command significantly higher per carat prices, and gems from 3 to 5 carats are very rare and much higher yet.

Prices are strongly affected by specific daylight and incandescent colors as well as the strength and percentage of change. Some sellers'' prices show a preference for the types color change from one location or another: some claim Brazilian is better than Russian and vice-versa. Indian stones in general (there are major exceptions) don''t display the strong nighttime red colors of the foregoing types but usually have a very nice daylight hue as Phantasmagoria discovered.

Alexandrite (chrysoberyl) is rated as a Type II stone by GIA, defined as usually eye clean with some inclusions under magnification. Clarity can vary by mining location. Brazilian alex is often very clean compared with Russian, Indian or African stones.

While alex from Tanzania and Madagascar may be very fine, those locations are known for producing color changes that differ from the traditional reddish-to-greenish of alexandrite. Only stones showing red-to-green change are graded as alexandrite. Non-red/green colors are graded as color-change chrysoberyl and bring lower prices.

No alexandrite treatments are presently known. The quality of cutting can affect alex pricing but if clarity, colors/color change and size are high-end, cut usually plays a minor role in valuation.

I probably haven''t covered all the bases but it just isn''t realistic to expect top colors and color change from low-priced stones. They are affordable natural stone choices for those with June birthdays or consumers who just want a genuine alexandrite.

Richard M.

richard, thank you for stating what should be obvious.....i''ll share the rant and also hope no one takes it personal.

a good quality color gem stone is going to cost some $$$ just like a good quality diamond. the stereotype that color stones are just not in the same league with diamonds persists, unfortunately. pricescopers over in rocky talk always advise against buying a diamond via ebay......imo, the same advise holds for anyone in the market for a good [or better quality] color stone. i understand budget constraints , but the same advise holds: you get what you pay for. there are a few posters [or were] who are collectors and have established a rapport with some vendors, even ebay vendors and have made some good buys: 1-because they took the time to learn about the stone and developed that rapport with the vendor and 2-they knew enough about the market that they were ahead of a stone becoming popular with the masses.

i also think it is very grand that there is a stone for every budget.....but the same holds true for diamonds. not everyone wants to or can afford to spend the time and money necessary to get a quality stone. that''s ok as long as the buyer has lowered his/her expectations to match the pay point. admittedly, while i have now developed an eye for some quality stones, alas my budget isn''t going to allow me the luxury of always buying a world class stone. but just like with diamonds, i''m going to always expect good color and cut and i''m going to sacrifice size to get the best i can for my budget. however, i never ever want to end up feeling like i settled for less. in my case, i''ll even change the color stone i want if my $$ will go further [better cut, color, etc.] with a different stone. i know i can''t afford a great sapphire and/or ruby.....but i might be able to get a pretty decent cabachon.

however, it really is up to each buyer and it really is in the eye of each beholder. however, your last sentence holds true for most color gems on the market.

 

[Phantasmagoria]

Date: 8/7/2006 7:49:03 PM
Author: Richard M.
All,

I’ve been building up to this little rant for a long while so I hope no one on the thread takes it personally. Briefly stated: genuine alexandrites with top color change are expensive. It would be a miracle to find such a stone at a low-priced auction site like EBay or from a mass Etailer like Thaigem.

Here’s a Reality Check. If you go to a site like THIS ONE you will be presented with an image of a top quality alexandrite, usually of fairly large size. Books and other internet sites usually show only top-of-the-line alex''s. Stones like that are rare and for perspective, below is an idea of current retail pricing of one carat+ stones. (Bear in mind sellers'' mark-ups vary and the prices shown here may be high for some dealers, low for others. They are examples only but are based on pricing data widely accepted in the gem trade.)

Lowest commercial quality: $400 to $1,600 per ct. Good quality: $1,600 to $6,000 per ct. Fine quality: $6,000 to $11,000 per ct. Extra Fine quality: $11,000 to $15,000 per ct. Remember: these price ranges are for stones from 1 to 2 carats. Stones from 2 to 3 carats command significantly higher per carat prices, and gems from 3 to 5 carats are very rare and much higher yet.

Prices are strongly affected by specific daylight and incandescent colors as well as the strength and percentage of change. Some sellers'' prices show a preference for the types color change from one location or another: some claim Brazilian is better than Russian and vice-versa. Indian stones in general (there are major exceptions) don''t display the strong nighttime red colors of the foregoing types but usually have a very nice daylight hue as Phantasmagoria discovered.

Alexandrite (chrysoberyl) is rated as a Type II stone by GIA, defined as usually eye clean with some inclusions under magnification. Clarity can vary by mining location. Brazilian alex is often very clean compared with Russian, Indian or African stones.

While alex from Tanzania and Madagascar may be very fine, those locations are known for producing color changes that differ from the traditional reddish-to-greenish of alexandrite. Only stones showing red-to-green change are graded as alexandrite. Non-red/green colors are graded as color-change chrysoberyl and bring lower prices.

No alexandrite treatments are presently known. The quality of cutting can affect alex pricing but if clarity, colors/color change and size are high-end, cut usually plays a minor role in valuation.

I probably haven''t covered all the bases but it just isn''t realistic to expect top colors and color change from low-priced stones. They are affordable natural stone choices for those with June birthdays or consumers who just want a genuine alexandrite.

Richard M.

Richard, i''m glad you were able to get that off your chest, but that has nothing to do with the questions asked. As i have said before in previous comments, i do not care about the quality, my question had to do with if it is alex or not. My beef with Taigems was not because it was low-quality, it was because the stone was not as pictured.

i understand that little rant was probably building up over time and finally it had the chance to come out, but i don''t want you to get the wrong impression about this topic.

 

[gemmy1]

Date: 8/6/2006 9:06:03 PM
Author: Phantasmagoria
Quantity: 1 Piece(s)
Approx Weight: 0.47 Ct.
Product Type: Alexandrite
Shape: Oval Cut
Size: 6 x 4 MM.
Color: Change Green To Purple Red
Clarity: Slight Inclusion
Origin: India
Hardness: 8.5
Specific Gravity: 3.71-3.74
Refractive Index: 1.745-1.757
Chemical Composition: Beal2o4
Orthorhombic
Treatment: None
Recommended
Retail Price: $1,468.00

I don''t know if that helps you, richard. It was an auction on e-bay. It may be poor quality but i''m not picky, i''m am only a poor college student that found out about alexandrites and was interested in having one. I don''t really mind if it isn''t naturally made, though here they say it is. As long as it IS an alex i''m happy.
Thank you all for helping me out with my question, and i hope to learn more about this wonderful gem.

If you don''t care if it is natural, why not get a lab grown true synthetic alexandrite? $1400 bucks is alot to spend on a poor quality stone. At least with the synthetic you will get nice color change, clarity and cutting.

 

[gemmy1]

While alex from Tanzania and Madagascar may be very fine, those locations are known for producing color changes that differ from the traditional reddish-to-greenish of alexandrite. Only stones showing red-to-green change are graded as alexandrite. Non-red/green colors are graded as color-change chrysoberyl and bring lower prices.

This is not exactly correct. One time when I was in Sri Lanka buying sapphires, I had the good fortune to be offered a very attractive large chrysoberyl that had just been cut. I looked at the stone and put a penlight to it and immediately saw a distinct color change. I quickly negotiated a price close to what the broker was asking and bought the stone. ( I didn''t want to risk actually paying the asking price as that would have raised alot of suspicion in that part of the world )

The stone was an attractive forest green in flourescent changing to a handsome almost cognac brown in incandescent. It was large and it was very clean and it was offered to me at a regular chrysoberyl price. When I got back to the states I sent it to GIA and it came back as "Natural Alexandrite". The color call was something like "yellowish green changing to yellowish brown". No mention of red, but I was nonetheless extremely happy to get that report.