THIS !!! is an alexandrite!!!!!

[Starzin]

WHOA........now I'm getting confused! So is a true lime to true lemon color (as in bright fluorescent colors) of Chryso still a chyrsoberyl? Or does that then become Alex because it shows two different colors in different light? No mud, just pure psychedelic Green and Yellow.............(I still think it's chryso)

I'm with you digdeep (and LD) - alex is green to purple, this is a CC chrysoberyl to me. Quite a pretty one I might add, three "clean as a whistle" citrus colours.

ETA: I might add though that CC chrysoberyl is not something I've seen mentioned much here because, well, who knew they could be this attractive?

Niel where are you? We have a new obsession for you

 

[T L]

It's a real shame that some dealers are selling color shift chyrsoberyl as alexandrite. I have seen some chrysoberyl go from yellow to brown even, and some dealers call that alexandrite. It's very disconcerting and deceptive. In any case, if I were to buy a chrysoberyl, I certainly wouldn't want it to shift to brown in certain lighting. I rather it stay yellow.

 

[chrono]

TL, LD, Chrono, and anyone who knows, what does muddy mean in alex then? Brownish? Opaque?

It's a vague term, and I think people can ascribe their own meanings to it.

I agree here as well, muddy is just a generic term for some sort of odd looking mishmash colours. Opaque is opaque though; I've not heard of anyone describing it as muddy in an alexandrite.

 

[chrono]

WHOA........now I'm getting confused! So is a true lime to true lemon color (as in bright fluorescent colors) of Chryso still a chyrsoberyl? Or does that then become Alex because it shows two different colors in different light? No mud, just pure psychedelic Green and Yellow.............(I still think it's chryso)

My understanding is that it is still a regular old chrysoberyl, possibly a colour shifting chrysoberyl.

 

[LoversKites]

TL, LD, Chrono, and anyone who knows, what does muddy mean in alex then? Brownish? Opaque?

It's a vague term, and I think people can ascribe their own meanings to it.

I agree here as well, muddy is just a generic term for some sort of odd looking mishmash colours. Opaque is opaque though; I've not heard of anyone describing it as muddy in an alexandrite.

Thank you both for clearing that up.

Chrono, LD did use the word opaque which is why I asked about it.

"I just call it a horrible greenie brown! I definitely wouldn't call this muddy because it's not opaque"
(I'm on my phone so using the BB code is annoying, sorry about that)

 

[LD]

Loverskites - you're right. I did use the term opaque. When Alex has an abundance of silk type inclusions it can take away the transparency of the gem and make it look smokey or opaque. Interestingly it enhances the colour change but at the expense of the beauty of the gem! I've attached a photo of one of mine - hopefully you can make out the smokey haze?

In terms of the word "muddy" it's not a great descriptor because it means different things to different people I think. For example muddy to me is mud brown that you can't see through but to TL it's a nasty unattractive brown gem.

I need to clear something up - there is NO such thing as a colour changing Chrysoberyl. Chrysoberyl doesn't change colour. The Alexandrite variety of it does. One of the most important differentiators between the two is that one changes colour the other doesn't. Having said that, the yellow to brown variety of Alex is just a poor quality variety! All gemstones have the ability to shift A LITTLE so I'm not saying that Chrysoberyl won't shift because like most gems it will BUT to change it will be an Alexandrite. *steps off soap box*

 

[chrono]

LD, in your opinion, is a clear and obvious shift/change from green to yellow an alexandrite or chrysoberyl?

 

[T L]

Loverskites - you're right. I did use the term opaque. When Alex has an abundance of silk type inclusions it can take away the transparency of the gem and make it look smokey or opaque. Interestingly it enhances the colour change but at the expense of the beauty of the gem! I've attached a photo of one of mine - hopefully you can make out the smokey haze?

In terms of the word "muddy" it's not a great descriptor because it means different things to different people I think. For example muddy to me is mud brown that you can't see through but to TL it's a nasty unattractive brown gem.

I need to clear something up - there is NO such thing as a colour changing Chrysoberyl. Chrysoberyl doesn't change colour. The Alexandrite variety of it does. One of the most important differentiators between the two is that one changes colour the other doesn't. Having said that, the yellow to brown variety of Alex is just a poor quality variety! All gemstones have the ability to shift A LITTLE so I'm not saying that Chrysoberyl won't shift because like most gems it will BUT to change it will be an Alexandrite. *steps off soap box*

Yes, and color "shifting" is completely different than color "changing." Typically, there can be a lot of brown in yellow stones, and sometimes a chrysoberyl, if it is a golden color (orangy to brownish yellow) can go from yellowish to more brownish yellow. That is shifting, not changing to a completely different color, as in the case of an alexandrite, like green to purple, for example. I think a lot of dealers take advantage of the ability of some gems to "shift" a lot to a modifier (grey or brown) or to a color next door on the color wheel (blue to violet for example) to proclaim the gem a color changer, and hence somewhat more valuable because of that. To me, this is deceptive. A color change is one that goes from one part of the spectrum, to a long distance to another part of the spectrum. Red and green are not next to each other on the spectrum, and therefore the change is quite distinct.

I have a chrysoberyl that looks very yellow in one light source, and very greenish yellow in another, and it's definitely a shifter, but NOT an alexandrite.

So for example, here's a bunch of chrysoberyls I photographed at a museum collection. Very golden in color (brownish orangy yellow), and in one light source, they may be more yellowish, and in another, more brown. They would not be considered alexandrite to me at all.

 

[LD]

TL I completely agree about the shifting/changing analysis which is why I was careful how I worded my post. Shifters are often marketed as changers when they're not!

Having said that, I did lots of research when I bought my vanadium chrysoberyl from AJS because I was surprised it changed colour (a very weak change but a change nonetheless).

I spoke with David W because I was very confused and he was absolutely crystal clear that if there's a distinct colour change then it's an Alexandrite not "just" a Chrysoberyl. I asked if the Vanadium component would change the diagnosis and he was very clear that it didn't and it was the colour change that mattered.

Marlow linked to a page from Alexandrite.net the other day that basically says the same thing in the first paragraph but the following paragraphs are not as explicit. However, considering on the MC website the yellow/green to brown/orange colour shifters with a strong distinct shift (and I appreciate they don't change across the colour wheel) are marketed as Alexandrite and not Chrysoberyl, I would say that any distinct shift/change means that the stone tips into Alexandrite territory.

I understand all the arguments for and against but my gut tells me that David is right and I've applied that reasoning since our discussion some years ago. Of course, he (and I) could be wrong! Oh and by the way, I would never buy a yellow/green to brown/orange variation as I don't like them and feel very snobbishly that they are not good Alex


EDIT: Here's an extract from Alexandrite.net that explains (much more clearly than I), what should be classified as an Alex:

"Only chrysoberyl displaying a distinct change of color should be designated as alexandrite. This means that chrysoberyl and alexandrite can be difficult to differentiate. Since stones with a weak change may be called alexandrite or chrysoberyl, the determination can be subjective. As the color change in alexandrite is due to the presence of chromium, and the color of yellow or brown in ordinary chrysoberyl is due to the presence of iron, spectroscopic examination will reveal these differences and help with identification. Chrysoberyl usually shows no fluorescence. The red fluorescence of alexandrite is evident using the "crossed filter" method."

NB: The Vanadium Chrysoberyl that I had, showed pink fluor. So if in doubt, get out the blacklight!

 

[T L]

I agree that murky green to reddish brown/orangy brown probably qualifies as an alexandrite, as in the "muddy" example I posted on the prior page. The stones I was referring to are more color shifters, and I also agree with you that I would never buy or want an alexandrite with such murky colorways. At the end of the day though, there can be a fine line between what is and what isn't an alexandrite, and I recommend that people do not pay for the name "alexandrite" but for what appeals to their eyes the most.

To me, color shifters are the following:

Brownish/orangy yellow to yellow
greenish yellow to yellow

Yellow is between green and orange on the spectrum, so the above examples are a shift, not a change.

 

[Marlow]

http://www.alexandrite.net/chapters/chapter5/index.html

I think Mr. W. is a bit inconsequent looking at his stock - ugly chryso or alex - it is still ugly!!!

I doubt you will get an alexandrite spectrum or red fluor with these greenish yellow to orange shifting chrysoberyl.

I will try to buy such a gem and ask Dr. Schmetzer ( my authority in alexandrite) to check the chrome, vanadium and iron content.

I will ask Dr. Hanneman ( he developed an alexandrite filter *) about his experience.


* a filter is always an additional tool!!!

 

[LD]

I agree that murky green to reddish brown/orangy brown probably qualifies as an alexandrite, as in the "muddy" example I posted on the prior page. The stones I was referring to are more color shifters, and I also agree with you that I would never buy or want an alexandrite with such murky colorways. At the end of the day though, there can be a fine line between what is and what isn't an alexandrite, and I recommend that people do not pay for the name "alexandrite" but for what appeals to their eyes the most.

To me, color shifters are the following:

Brownish/orangy yellow to yellow
greenish yellow to yellow

Yellow is between green and orange on the spectrum, so the above examples are a shift, not a change.

Completely agree with all of the above BUT if some of those horrible shifters have a red/pink fluor then DW classifies them as Alex.

 

[Marlow]

The spectrum is more important imo - handheld or this...

http://www.cigem.ca/research/GLGemSpecPromo.pdf

Usefull for diamonds too - but I fear you need support to calibrate it and some "masterstones"

Crossed filter is very easy and quick and you can check several alex parallel.

 

[Marlow]

Maybe this is interesting...

http://www.gem-a.com/media/95198/article%205%20schmetzer%20lake%20manyara%20final.pdf

Alexandrite and color change chrysoberyl from Lake Manyara....

 

[LD]

Maybe this is interesting...

http://www.gem-a.com/media/95198/article%205%20schmetzer%20lake%20manyara%20final.pdf

Alexandrite and color change chrysoberyl from Lake Manyara....

I don't do this many words! Having said that, figure 40 and the words beneath it demonstrate there are differences of opinion in the trade as to exactly when an Alex is an Alex or when it may be a chrysoberyl. Also, interestingly, in figure 33 I wouldn't have placed stones 1, 2, 3 and 6 as Alex (although 1 would be shown as such on MC) and this is discussed in that article on page 28 of 31 in the first column with the paragraph starting "Using the Lake Manyara stones ...........".

One of the conclusions states if there is not a red component to the incandescent colour way then the author wouldn't classify that stone as an Alex (which makes sense).

 

[digdeep]

Marlow..........yup, that was interesting until my eyes glazed over. I thought I read that there can be a green to yellow CC Chryso/ Alex. Although you need a LOT more scientific analysis to define most of the perimeter color changes. Is that anywhere near the gist of the article.......and if not, can you summarize..........Please???

 

[Marlow]

Marlow..........yup, that was interesting until my eyes glazed over. I thought I read that there can be a green to yellow CC Chryso/ Alex. Although you need a LOT more scientific analysis to define most of the perimeter color changes. Is that anywhere near the gist of the article.......and if not, can you summarize..........Please???

Please understand that I am not able to summarize this article in an acceptable quality.

LD posted the figures which are interesting (33, 40) - I agree with her post.

I think - and I posted this several times ( and no answer to this...) - the amount and ratio of chrome ( resp. for the CC), vanadium and iron
is important and the key to understand alexandrite.

You see that the daylight color in figure 33 is quite similar but the incandescent color differs - 1,2,3,6 and I think the bluish gray too do not show the classic CC - honestly - No. 1 is closer to alex than the green to bluish gray ....

I will read this article course I discovered it yesterday late in the evening - Dr. Schmetzer worked on many Alexandrite locations and other chrysoberyl variaties ( Vanadium etc.) - he published also a laaarge article on CC garnet.
I think figure 40 is worth to think about and .... it is a discussion in trade so will discuss too. We have to accept that their is no wrong and right. Their will be always borderline stones...

 

[digdeep]

Figures 33 and 34 were pretty specific in color ranges (diversity).......I read fig. 40 (and discussion) as mostly an orientation with axis discussion.
It still seems to come down to what is aesthetically 'pretty' (extreme color changes) vs what appears to be scientifically valid mineral compositions that can show less than extreme color change. (See #'s 2 and 6 on fig. 33)...........
In the end........gemstones are often labeled one way for the benefit of commercialism, while science has sneaky ways of not showing everything as clearly as cash registers!!

 

[chrono]

Digdeep,
I agree; this sounds very much like the line between ruby and pink sapphire. It depends on who is selling and who is buying.

 

[Marlow]

Digdeep,
I agree; this sounds very much like the line between ruby and pink sapphire. It depends on who is selling and who is buying.

But again !!!!

Multicolorgems is a highly respected vendor and I recommand them - why ??

The price reflects the quality - for premium alex a high price - for lower qualities a fair small price !!! And some are really interesting!!!

 

[LoversKites]

Interesting discussion which I have nothing to add, as usual

And thanks LD for explaining what you meant by muddy.

 

[LD]

Interesting discussion which I have nothing to add, as usual

And thanks LD for explaining what you meant by muddy.

Do you mean opaque?

 

[LoversKites]

Interesting discussion which I have nothing to add, as usual

And thanks LD for explaining what you meant by muddy.

Do you mean opaque?

Yes! Oops.

 

[Marlow]

Think this is very interesting - esp. the last post of Mr. Smith (AGL)

You see the Alex if you download the pdf on the GIA site.

http://www.gemologyonline.com/Forum/phpBB2/viewtopic.php?f=6&t=20374&start=30

Hope it is o.k. to post the link - a very good addition to our topic here.

 

[irinaalexandrovna]

What do you think guys about these earrings?:
This matching pair of 14k yellow gold natural alexandrite earrings is set with Brazilian alexandrite faceted gemstones weighing 1.03 carats total weight. This pair of genuine alexandrite gemstones has deep green color when worn in daylight conditions (see photo at left), and they show a strong natural color change to purpleish-red hues when viewed under incandescent light

Thanks!

Irina

 

[chrono]

1. Is the vendor reputable? (Good return policy and full refund)
2. How accurate are the pictures? I'm surprised to see a perfect green pictured.

Not knowing the vendor nor having familiarity with the vendor, I would want to find a way to authenticate that these alexandrites are not synthetics or simulants.

 

[irinaalexandrovna]

1. Is the vendor reputable? (Good return policy and full refund)
2. How accurate are the pictures? I'm surprised to see a perfect green pictured.

Not knowing the vendor nor having familiarity with the vendor, I would want to find a way to authenticate that these alexandrites are not synthetics or simulants.

I guess http://www.mineralminers.com is reputable. It has been mentioned on this forum.
Isn't the green too dark?

Thanks!