I need a little help

[joeygo]

I found this ring about 20 years ago.Can anyone tell me what kind of stone it is? The size of the stone is about 15mm x 13mm.It changes color from violet to blue,green,and red.Depending on the lighting.It''s very pretty and I''m wondering if it''s worth resetting?Thanks in advance for any help.------------ Joey

 

[WinkHPD]

It is impossible to say for sure without inspecting the stone in person, but it looks like synthetic alexandrite-like sapphire, which would account for the color changes.

Of course, that is a mere guess, and not to be taken as a statement of fact!

Wink

 

[glitterata]

I have one in a similar setting. I wouldn't reset it. The stone itself isn't particularly vaulable (that is, assuming it's the synthetic sapphire Wink describes; mine is), and the setting is so very much of its time--it's a fun, vintage piece.

If you like the stone and want another setting, you could probably get a whole new stone for not a lot of $$.

 

[joeygo]

Is there a way that I could tell if it's synthetic or not?I feel that it probably is not a "real" Alexandrite It also has a what I believe to be a jewelers mark on the inside of the ring.How would I track down who made it.Part of the fun is the chase.Thanks again--------Joey

 

[Nicrez]

Well "real" Alexandrite is a color changing Chrysoberly. It usually green in daylight/florescent light, and changes to brownish or purplish-red in incandescent night, like lamp light or candle light.

It's about a 8.5 of on the Moh's scale, so that would mean that it could scratch anything softer, like Quartz or feldspar. To tell if it's synthetic, you would truly need to take it to a Gemologist or appraiser who can do test on it, such as a refractive test or other such tests.

Some facts about a natural Alexandrite which make it quite pricey...especially at that size.

It would have fingerprint like inclusions, silk, and must change color.

Refractive index: 1.746-1.755 (+.004-.006) - would be the same as the synthetic
Birefringence: .008 to .010
Dispersion: .015

Also, doing a test such as one with a Spectra Scope would show that it has a very specific spectra, even in it's color change, and that may be evident from such a test on a synthetic.

Most likely the magnification of the gem would show the inclusions to be appropriate to a natural gem, or the synthetic may exhibit a slight florescence.

If it was an imitation, it would depend on HOW it was made, as there are 4 main ways, so you could differentiate the inclusions form the natural gem. SOme of the inclusions on sythetic include:

Flux method: veil-like inclusions, tubes or parallel planes of flux, hexagonal, triangular or
trapezoidal metallic platelets, straight growth lines

Czochralski method: needle-like inclusions, carves striae

Floating zone: gas bubbles, swirled appearance

Undulating growth lines in cat's-eye variety (which you obviously don't have)

Again, my guess is that at that size, if there are no visible inclusions to identify the stone, it is most likely a synthetic or a really really rare and expensive stone... so check the inclusions and the florescence, which would show a moderate to strong red in UV light...

Either way, it's lovely, enjoy it!!!!!

 

[DiamondExpert]

For what looks to me like what might be a 20-30ct. stone, a natural Alex that size with good color change would run you at least 6 figures, so if you paid a lot less than that, it's either not a natural stone, or you got the deal of the century!

 

[chialea]

if it's pretty and you like it, why not reset it? I wouldn't spend too much on the setting, perhaps, but it looks like a pretty colour. perhaps in a yellow gold setting with some filligree or flowers around the edge?

 

[joeygo]

Thank you for all the help.I really know nothing about stones.I've been looking through a 10x magnification and I can see very small bubbles and some imperfections. Like I said,I don't know what I'm looking at.Maybe I'll do some more checking and at the same time educate myself.Would anyone have an idea what a manmade Alexandrite like this be worth.Again thank you for the advice.Here is another picture that I took in the daylight.Thanks-----------Joey