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2,90 carat Ruby?

Hello everybody

I am a new member at IGS, but i have been reading IGS for a long time.
I have a question about a ruby, that my wife inherited from her grandfather 7-8 years ago.
I dont know too much about gemstones, i have only bought and sold south sea pearls and invested in gold / silver.
My scale shows 2,9 / 2,95 carats or 0.58 / 0.59 grams, so i think the ruby is between 2,9 and 2,95 carats.
When i use a uv light on the stone, it fluorescence a strong red blood color.
I would very much appreciate any information or thoughts you might have about this stone.
Like its origin , quality , value etc.
Thank you very much

Hello DaveTT.

My first opinion just by looking at the pics is that might be a synthetic ruby. Have you checked it in a microscope for growthlines, inclusions, bubbles etc?


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I have seen , what looks like a calcite crystal and a finger print inclusion.

Photo 6f reminds of a surface I have seem in reheated (and lead glass injected rubies). Ruby of inferior quality with clarity characteristics is heated and lead glass is added to fill fractures. You may want to try an immersion looking for the original ruby andlead glass.

Anybody knows what this might be ? ( its a bit hard to see ).

Highly suspicious of flame fusion synthetic ruby

have you checked refractive index?stone looks like is cut en cabochon.more testing needs to be done before value and origin and quality can be determined.

An almost 3 ct natural ruby of that clarity and color would be well over a thousand dollar purchase…my price guide gives $1000/ct at grade 5 and this is much better than that, probably at least $4000/ct. I’d suggest that if your wife and her grandfather were on speaking terms, he probably would have noted that he had a $10,000+ ruby if he’d purchased such. The fact that it wasn’t noted as that or set in gold or platinum argues for it being some kind of synthtic or glass filled stone. If you think it is worth spending money on an appriasal, I would get one. If not, wait until there are gem shows again…they usually have a gem ID booth or some gemologists around who might give you an ID off the cuff for free. AFAIK, a strong fluorescence is not an indicator of natural vs synthetic. If you have a good loupe or microscope, you could look up the subject of inclusions in natural and synthetic ruby and try to ID it yourself. I would not expect a bonanza, as the odds of having a 3 ct natural ruby in a drawer somewhere are unlikely without family knowing of it.

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Good day!
I am of the opinion, as are some of the commentators. - that the ruby you presented is synthetic.
They have been raised since the end of the 19th century.
Another thing is that it is extremely difficult to carry out diagnostics using the photo + complicates the matter - the type of cut is a kabashon.
If possible - you need to conduct a gemological study in the laboratory, but the result and procedure can cost much more than the ruby itself, if it is synthetic.

You should check to see if it is not a spinel
Scales, water, and thread.
ruby 3,99
spinel 3,57