Opinion on possible small Emeralds

[Alex_Paul]

I would be grateful for any opinion about possible small Emeralds. They have been part of a silver jewelry with not very good design and that is the reason I pulled them. The weight is about 0.65 ct each and the density is about 2.67.
Thanks in advance,
Alex

 

[minousbijoux]

What makes you think they are emeralds?

 

[Alex_Paul]

I am not the professional jeweler. The color looks very much like Emerald , density. Also the same jewelry had real red garnets , so I thought these might be real Emeralds. :roll
Alex

 

[Alex_Paul]

Sorry, that was the error of calculation. The density is more like 4.0 or even a little bit higher.
Can it be green garnet ? Are there variations of green garnets with density a little higher than 4 ?

 

[Seaglow]

It could be synthetic sapphire.

 

[Alex_Paul]

I am not an expert again, but these stones appear to be glowing like garnets. It doesn't mean they are natural of course.

 

[Seaglow]

The reason I wrote that it might be synthetic sapphire is emerald, tsavorite, demantoid, green grossular, tourmaline, and diopside which are the stones that occur in that color have a lower density than 4. And synthetic sapphire that color are sold in the market as imitation for emeralds and green garnets.

 

[Alex_Paul]

Thank you for your reply. The problem is that these stones are too small and I might be mistaken about the exact density. Also I have the synthetic sapphire and simple diamond tester - the measuring is very different for these green stones and sapphire (the sapphire shows higher conductivity).
Thanks again,
Alex

 

[T L]

I think the the fact that they are so clean, raises a red flag that they might be synthetic. A good colored stone gemologist should take a look to discern if they are natural or not. Also, unless these gems were in Victorian era jewelry, or a custom pair of earrings you or someone else had made, why would they be in silver? Commercial silver jewelry typically denotes colored stones of lesser value, like synthetics.

I'm not saying with 100% certainty they're synthetic, or perhaps simulants (i.e. green glass, synthetic Quartz), but they could be.

 

[pwsg07]

It is hard to see the stones in your photo. We need a brighter photo to make any judgement.

 

[Alex_Paul]

Thank you for your replies. I will try to make better photos under day light.

 

[chatoyancy]

Could they possibly be chrome diopside? I could see those before by set in silver. Ask a jeweler.

 

[Alex_Paul]

Yes, I agree that the best way is to ask for the beginning some well-qualified jeweler.

 

[Alex_Paul]

I went to a couple of local jewelers and they don't know what it is. Actually they told me that local jewelers know only obvious things such as diamonds, clear cases of sapphire , emeralds, but not other rare variations of colored gems.
I measured the density , it is close to 4.0 , also I would think the stones look very similar to Russian demantoids, but w/out inclusions and that is the red flag. Also I think the quality would be too good
to be true. I am attaching a couple of pictures of demantoids from the web along with my stones.
Alex

 

[T L]

I am highly doubtful they're demantoids because you rarely see demantoids in a long oval shape. Their crystal structure lends itself best to cushions or rounds. The demantoid you have depicted is a very high quality one worth $$$ and no way would it be set in silver.

I'm thinking they might be chrome diopside, an inexpensive green stone that you often see set in silver. No way to know for sure though without appropriate testing.

 

[Alex_Paul]

I have a candidate for possible chrome diopside, or even for Chrome Tourmaline.
It was set in silver. The only problem is that it is too large - 75 ct. Does it mean that it is
most likely synthetics or glass ? Images are attached. Sorry for the bad lighting. Live I think it has
pleochroism - green and yellow. The density is 3.24 .
Thanks in advance,
Alex

 

[partgypsy]

The ovals look like chrome diopside, just a guess. Their specific gravity is 3.22 to 3.38.
Tourmaline is 2.9-3.1 density.
There are tsavorite garnets that look like that, but they probably would not be set in inexpensive jewelry.
They don't look like emerald or demantoid garnets.

As far as the 2nd stone, where you got it, what they said it was, and how much you paid for it should give you a clue. If I had to make a wild guess, lead crystal glass, simply from the size, price and clarity.

 

[Alex_Paul]

Thank you for your reply. The ovals are a little puzzling, because their density is about 4.0,
I measured several times. The problem is when I looked through 60X loupe - there is extremely small bubble inside , not sure if it is air filled or something else, but it is a bad sign. The diamond tester shows conductivity of approximately - garnet, but definitely not corundum (I thought it is synthetic green sapphire).
Second large stone was bought indeed cheap on eBay from US dealer who sells many such silver rings, but not with these large stones. It attracted me because it is sparkling very much and half of it becomes yellow, when rotating, but it sparkles with small other colors including dark blue. I read that diopsides are up 3.4 and tourmalines up to 3.3, so it appears to match both. Also on the internet they say that there is no synthetic chrome tourmalines and they are emulated by spinels, but I agree that it is very improbable that it is a chrome tourmaline of such size.
Btw, I just read the article about chrome tourmalines at gemselect.com and tried to rub the large stone against the wool and it indeed picked up the small piece of paper, so it gets the magnetism,
after mechanical friction (piezoelectricity ?), not sure though if it indicates anything.
Thanks again,
Alex

 

[Seaglow]

Small stones can be "low" zircon. Big stone can be synthetic diopside as you'd be lucky to have a natural diopside more than 10 carats (based from the densities you've given and thermal conductivity on the small stones).

 

[Alex_Paul]

Interesting, thank you for the reply. I agree that the large stone looks like synthetic, because it is too clean and looks "new". But I read that chrome diopsides are not pleochroic , probably the same for synthetic. Can it be some "generic" synthetic crystal ?
Regarding small ovals - is the silver setting the main reason for not being demantoid. Also with density of 4.0 are there other than corundum synthetic materials. I am thinking that whatever these gemstones are if they are natural they can be worth something.
Thanks again,
Alex

 

[Seaglow]

You said that the density is 4. Demantoid tops at 3.85 so it cannot be demantoid. Demantoid also has a higher dispersion than diamonds and though your photos are limiting, it doesn't show that.

Flint glass can also reach a density of 4.

 

[Alex_Paul]

Ok, thank you, probably I used the wrong source of information. There is a fragment of book on Google called Gemstones of the World
by Walter Schumann.
He says that Andradite (includes Demantoid) has the density 3.7 - 4.1. But probably Demantoid itself has lower density.

 

[Seaglow]

Ok, thank you, probably I used the wrong source of information. There is a fragment of book on Google called Gemstones of the World
by Walter Schumann.
He says that Andradite (includes Demantoid) has the density 3.7 - 4.1. But probably Demantoid itself has lower density.

I used Liddicoat and GIA's Gem Identification Lab Manual. Andradite's SG is 3.84 (+/- 0.03).