A Real Gemstone?

[lewood]

I've recently come into posession of an emerald cut aquamarine gemstone. I am unsure if it is real or not, and I have not had the chance to head over to a jeweler to have them determine if it actually is. As a result, I am wondering if there is any way for me to determine, on my own and in the mean time, if the stone is a genuine aquamarine? Furthermore, how exactly does a jeweler determind if a gemstone is real or not?

Thanks for your help!

 

[LD]

I'm very sorry but you're asking the impossible. It's incredibly difficult to identify a gemstone from a photograph. We might be able to have an educated guess if the photo is very good BUT it will be only that. A guess.

If you take it to a jeweller they should be able to check the gem's refractive index which will narrow it down, then they can look at whether it's doubly/singly refractive, look at the specific gravity etc. However, these rule out some things but not others. It will give a general indication but won't be definitive. Unfortunately there are tons of synthetics and simulants on the market so the only real way to be 100% sure with absolute clarity is to send the gem to a laboratory for testing. That would give an absolute answer.

 

[Michael_E]

Determining if the stone is a natural aqua could take a bit of equipment, but if it has any inclusions then the job has just gotten easier. Do you have a loupe? Hold the stone in bright sunlight so that the loupe and area behind the stone are shaded. As you're looking into the side of the stone, (NEVER look in direction of the sunlight with a loupe, since it won't show you anything and will damage your eyes), the bright oblique lighting should highlight any inclusions that are present and those inclusions can indicate that the stone is definitely natural and that it probably is an aqua. The inclusions to look for are what looks like fine silk but are all running in the same direction. Sometimes they are widely spaced and can have small dark spots that aren't visible to the naked eye. If you can't see any inclusions, then you're out of luck and would probably need to have the stone removed from it's setting to have it's specific gravity, refractive index and other features checked.

 

[lewood]

Hmmm....sounds like this is a job for a jeweler! I don't have a loupe, so chances are I won't be able to determine if this is a real aqua or not. Luckily the aqua is not set, which, I take, will make it easier to scope out.

Will any jeweler be able to check this aqua out for me? I kind of live in the middle of nowhere- independent jewelry stores are far and few.

 

[Largosmom]

This is a job for a gemologist....not a jeweler. Some jewelers are also gemologists, but some are only sales people. Call ahead and see if there is a graduate gemologist at the jewelry store. They will know how to identify various stones due to their schooling. Just ask if they have a G.G. on staff and when that person works so that you can bring the stone directly to them.

I didn't understand the difference myself until about a year ago, but it's really important as some sales people will tell you most anything to make a sale.

Laura

 

[T L]

Well, it could be a natural gemstone, but not necessarily an aqua. It could also be a synthetic gemstone. A combination of an RI test and some inclusions would be necessary to determine if this was a natural aquamarine. There are many simulants for aqua though, like synthetic spinel, synthetic corundum, natural blue topaz, and even blue glass. Aqua is blue form of the mineral beryl, and it shouldn't be too difficult, with an RI test, to determine if your stone is also a beryl. I had an aqua id'd before, it took all about five minutes with a refractometer from a gemologist. At the time, I don't believe synthetic beryl was being created, but it could be today, so natural inclusions might be necessary to determine if it's natural as well.

 

[Deathspi]

Sorry to threadjack but I've been wondering about this for a while now. Is there a way to distinguish between aqua and light blue topaz, or is that too, a case of looking at the RI? I have some small loose stones of both but I swear if they weren't labeled I wouldn't be able to tell what was what!

 

[blithesome71]

Same here. I'm wondering if aside from the inclusions, can you also tell if it's real aquamarine by its fluoresce under uv light... 'cos I have this gem that was sold to me as "aquamarine" but it fluoresce strong yellow green/apple green under black light (those used for detecting fake money bill)... It has a silvery brilliance w/ very fine silk & tiny needles running on the same direction (like rain drops of micro needles) in its pavillion... Visually, it looks beryl. But the thing that bothers me is its yellow green fluoresce... Perhaps I could send it to Michael E. for gem identification hehe

 

[LD]

Basically there isn't one test that will give you a definite "yes it is X". The tests you can run at home (or a gemmologist at a local jeweller can do) will point you in a direction but they WILL NOT give you a definitive answer because there are so many simulants, synthetics on the market AND some now have inclusions that can fool even those who are used to looking at them.

So, for example, the RI of a natural Alexandrite is 1.741-1.760 (the Chrysoberyl family). However synthetic corundum (ie material that looks like a natural alex and will be sold as alex) will reveal a refractive index of 1.759 - 1.778. So (a) you have to be able to read the RI correctly AND (b) know that your machine is calibrated correctly. The ranges are so close that you may want to run more tests because this will only be suggestive. However, if the gemstone you're looking at is reading something completely different then you can be sure that it's not a natural Alexandrite. It doesn't tell you what it is but you then look to see what other gemstones test in the range you've found. You then need to look at inclusions, the SG of a stone and what you see with a spectroscope. Together those things will give you a good idea and you'll probably be right BUT as TL has said, unfortunately, nowadays technology with simulants is getting so good that the only sure fire way of being sure is with lab testing.

For example, I have been collecting for many years and am used to looking at inclusions. I can also conduct RI tests and various others. Would I be able to say that X is definitely X? No. I would probably be able to get to an 80% "I'm pretty sure that this is X" but for some gemstones the only way to be 100% sure is by lab testing. The 80% is good enough for me if the gemstone is not a significant purchase. For significant purchases I would want a lab report.

 

[Michael_E]

Same here. I'm wondering if aside from the inclusions, can you also tell if it's real aquamarine by its fluoresce under uv light... 'cos I have this gem that was sold to me as "aquamarine" but it fluoresce strong yellow green/apple green under black light (those used for detecting fake money bill)... It has a silvery brilliance w/ very fine silk & tiny needles running on the same direction (like rain drops of micro needles) in its pavillion... Visually, it looks beryl. But the thing that bothers me is its yellow green fluoresce... Perhaps I could send it to Michael E. for gem identification hehe

Aquamarine is colored by iron and so it is generally inert under UV light, so that stone is unlikely to be an aqua. I'd have someone check it out and see what it is as that sounds interesting.

 

[Michael_E]

AND some now have inclusions that can fool even those who are used to looking at them.

Outside of healed fingerprint and silk type inclusions in sapphire I can't think of any other gems which have inclusions that can be mimicked in synthetics. If you have some good references for this I'd sure be interested in reading them.

For example, I have been collecting for many years and am used to looking at inclusions. I can also conduct RI tests and various others. Would I be able to say that X is definitely X? No. I would probably be able to get to an 80% "I'm pretty sure that this is X" but for some gemstones the only way to be 100% sure is by lab testing. The 80% is good enough for me if the gemstone is not a significant purchase. For significant purchases I would want a lab report.

You ought to check into the "Hodgkinson Method". It's an excellent way to tell what you're looking at with a little training. Here's a link to an explanation of this and how it was developed: http://www.nordskip.com/hh.html As a good example of the use of this it is easily possible to tell the difference between light blue sapphire, aqua and topaz by just looking at them. Topaz and aqua are very difficult to tell apart without getting their specific gravities, but the spectral colors produced when viewing them are enough different that after some experience it is hard to get fooled, (aqua passes most of the yellow light entering it while blue topaz doesn't and this is pretty easy to see in their spectral color display). As for telling synthetic from natural in anything but sapphire, well it's pretty easy and a lab report for something like tourmaline is completely unnecessary IMO, (unless you don't want to mess around with learning how to tell what you're buying...and then a fake lab report looks as good as a real one, so you could still be in a pickle).

 

[T L]

I know this isn't definitive, but I find most aquas to have a strong grey cast, much more so than a blue topaz. If the stone is a very saturated or vivid blue, I would be suspect it's not an aqua. They rarely ever come that saturated.

 

[LD]

AND some now have inclusions that can fool even those who are used to looking at them.

Outside of healed fingerprint and silk type inclusions in sapphire I can't think of any other gems which have inclusions that can be mimicked in synthetics. If you have some good references for this I'd sure be interested in reading them.

In synthetic Emeralds, you may see natural inclusions i.e mica flakes in Zambian & Pakistan emeralds or three phase inclusions seen in Columbian emeralds. With Chatham Rubies you may see fingerprint inclusions or feathers. Correct me if I'm wrong, but you might also see those same inclusions in the natural gemstones?

I guess my point is that inclusions are not definitive and more importantly, it takes many many many years of consistent practice to be able to identify (correctly) inclusions. It's easy to assume that somebody can pick up a loupe and then understand what they're seeing. I would think that for you Michael it's something you do everyday and so is second nature. I've been looking at gemstones for years and struggle to identify everything I see.

You also need a good understanding of (a) what is/isn't normally seen in a particular type of natural gemstone and (b) if something is out of the ordinary identifying what it is and whether it would be something that has occurred naturally or is a by-product of a man made process.

So, just by way of an example, if you see a bubble type inclusion in a Ruby/Sapphire, it may be indicative of a treatment or synthetic. However, seeing a bubble in a spinel would be less alarming and actually might be more reassuring (correct me if I'm wrong as I am a million miles away from being an expert in this matter)! In my opinion, the average layman with their loupe may struggle to understand the difference.

 

[Deathspi]

I know this isn't definitive, but I find most aquas to have a strong grey cast, much more so than a blue topaz. If the stone is a very saturated or vivid blue, I would be suspect it's not an aqua. They rarely ever come that saturated.

That's exactly what I would presume too, but unfortunately these stones look exactly the same...

I really hate being 'pretty sure' that something is something, though I know it's not always the case that you can look at a stone and identify it straight away. Oh well, I'm learning more all the time and maybe one day I'll be able to tell the stones apart!

 

[T L]

When in real doubt, and you don't know who you can trust, send it to a gem lab. AGL, for example, charges around $65 for a simple id report. That being said, the stone might not even be worth $65 (even if it is a natural aqua), but if you're dying to definitively know, without the shadow of a doubt, send it to a REPUTABLE gem lab.

 

[Deathspi]

Well I don't know about the OP, but the stones I'm pondering over are very small and very crappy, rescued from someones old jewellery actually, so not really worth it!

 

[colormyworld]

Sorry to threadjack but I've been wondering about this for a while now. Is there a way to distinguish between aqua and light blue topaz, or is that too, a case of looking at the RI? I have some small loose stones of both but I swear if they weren't labeled I wouldn't be able to tell what was what!

I remember reading somewhere that topaz will feel more" slippery" than beryl when held between your thumb and forefinger.

 

[Richard M.]

As for telling synthetic from natural in anything but sapphire, well it's pretty easy .

Michael, do you care to share with us an "easy" method for distinguishing natural aqua from man-made hydrothermal "aqua" beryl? I'm sure there's a lot of the latter being marketed as mined aqua, especially on EBay.

Actually, natural aqua can be difficult to sort out if there are no loupe-visible inclusions. And being a Type I gem, it's often very clean. It's easy to detect glass, synthetic spinel, zircon, CZ and a few other aqua simulants but the hydro synthetics are a very different matter. Many people even in the gem trade are still not aware they exist. Few amateur gem fanciers are equipped with 60-power microscopes and the knowledge/experience with immersion microscopy required to detect their cellular structure.

Richard M. (Rick Martin)

 

[T L]

So there is synthetic beryl out there. I think, if I remember correctly, it was being used as a paraiba substitute from Morion (a synthetic manufacturer). My memory is coming back.

Yes, if it's too clean, then the only way to probably tell is to send it to a gem lab with sophisticated ID processes.

If it's a "crappy gem" as the OP stated, and it's not worth the time, then just enjoy it for what it is, and don't let it keep you up at night. It probably isn't worth very much anyways.

http://www.morioncompany.com/NewMaterials.htm