I’m sorting through an old Ex Jewellers collection of Zambian stones and I’m coming across the odd one that is much more blue than green. See the stone 3rd from left on second row.
Is this still considered an emerald? The largest stone in the image is .92 cts.
When is an emerald not an emerald?
Many thanks for your kind knowledge.
Hi Mark,
Its not a true diagnostic test, but a Chelsea Filter would definitely come in handy here. Most emeralds will look red through the filter. An aquamarine will be a dull green.
I have the Hanneman Chelsea-Filter pocket set. The kit has a few other filters that help distinguishing the varieties of beryl and synthetics. There are some good quality loupe style filters out there as well.
Of course, the only way to know is to perform the standard set of ID tests: RI, SG, Optical figure and spectroscopy.
The second and sixth stones in the top row (from the left) also have more bluish tones. 
Have to say… though… that the largest parcel of “potential” emeralds, I have seen in one place…
Cheers!
Hello Mark,
By definition, emeralds are medium-green, dark green, or blueish green beryls with chromium and/or vanadium impurities. Putting aside the question of whether or not these gems are beryls, the stone you note as well as the ones TroyJ49412 notes do appear more blue than green. Have you examined the color of those stones individually, separated from the other gems? Perhaps the colors of the neighboring stones are making them appear bluer when they’re lined up.
Pedro
IGS Admin
Hi Troy,
Thanks for the detailed reply. I do have that filter set you mention and according to Miss Addison Rice in the first link you posted Zambian stones don’t glow red. I’ve had a couple of the stones professionally examined and they have been determined to be Zambian stones. To do it for all the stones would be cost prohibitive for me.
I’ve done a bit more research now and have found that the bluer stones are called seafoam blue. They don’t appear to be that common but I only have limmited knowledge in that regard.
The collection I’m having to deal with was found in a garage in a box stored in deteriorating browned ziplock bags. The stones had obviously been oiled in the past and had dried out. There was no rhyme or reason to the way they were stored as there were even some loupe clean stones stored with what I would call absolute rubbish stones.
Here is an image of one of the bags that I call rejects. They have brown staining or reflective feathers and the like viewable from multiple angles. The largest stone in this image is 2 cts.
The original image above I posted was a selection of stones that I consider presentable to the eye without such flaws. Yes it is a large collection but not my area of expertise.
Cheers, Mark
Hi Pedro,
Thanks also for your reply. Please see the answer I gave Troy above. I’ve been going a bit colour crazy looking at all these stones but even when separated they still appear to be more blue in my eyes. I even showed some to a local Jeweller who worked previously for a gem wholesaler for a decade recently and she even thought it was unusual and appealing to see the more blue coloured stones. It’s a large collection that is decades old so I guess I can expect some anomalies.
Cheers and thanks,
Mark
Congratulations on a good find regarding this collection. I hope you got it for a good price. That being said, as you already know, even the stones you culled out and call “rubbish” are still desirable to some people. I hope you get the answers you are seeking. There are a lot of good people on here.
Thanks for your reply Oldtroll.
I think I have to revisit the rubbish bags now. I do agree there are many good people in this forum and group. I do enjoy reading the good advice that many give here.
Cheers,
Mark
Hi Mark,
Apologize, for some reason I overlooked your initial comment about the stones being from Zambia. Zambian mines can and often produce more blue tinted material, as well as other localities like Muzo, Columbia. Unfortunately, most Zambian stones will be non-responsive to the Chelsea Filter.
Since several localities of emeralds can be identified by the type of inclusions they contain, I am curious what diagnostic was used to prove they were from Zambia? This is more for my own curiosity and I am sure others would be interested in knowing that information as well.
I also agree with @oldtroll57. Not one of those stones unless shattered or broken, should be considered unsellable! If they are emerald, which is a type III stone, always with some type of Jardin (inclusions) they can still have good sellable value.
Cheers!
Troy
Hi Troy,
No need for apologies as I read some things quickly too and miss details. Regarding the diagnostic used to tell that the stones are Zambian of origin, I believe it comes down to 2 factors, the high Iron content and the presence of skeletal ilmenite inclusions that are not found in other regions that produce emeralds. A few years back when I decided to start looking at what I had I did some microscopic examinations and posted some questions to this good forum with a title of Emerald spot inclusions. Please look that up as this was a preliminary before I had a couple of stones examined further.
Here is an excellent link from the GIA that mentions the tests that can determine the origin of a stone species by country. It’s an exciting thing now that science can now in relative definitive terms via the elemental makeup of the stones. But like I mentioned it is often cost prohibitive.
When it comes to the stones that I call rubbish or unsellable please point me in a direction of a person that would buy them for a fair price. None of them are damaged. The damaged stones I have in another bag that I’ll be putting under new trees I will plant on my property for good luck. I’m sure they need a treatment that is greater than the oil they were treated with decades ago. I don’t find the black and stained brown spots or the feathers and clouds appealing. It’s a mixed bag of around 30 cts that I imaged above. I’d sell them and give the proceeds to a charity. I don’t need the money but I’m sure that someone else does and I would show the moderators of this forum the receipts.
I donate to many charities monthly as I understand that many in this world are in unfortunate positions.
Thanks for your reply.
Mark
Hi Mark,
Thank you! That article is an excellent read which links to the original one you posted back in 2022 (another excellent resource).
I read your original post with @JCBellGG, @royjohn, and @beargems. I cannot agree more, this forum has many experienced members that I have learned and continue to learn from about gemstones and the industry! 
Have you attempted to clean the stains from any of the stones? It would be interesting if the surface stains could be removed from using swabs with isopropyl alcohol.
The IGS forum and site is full of excellent information… just found this one:
I have a couple of Zambian emeralds in my collection, that I still need to perform the diagnostics on. Unfortunately a few other projects have been keeping my focus away from doing so.
Hopefully, I can jump back into doing gemology stuff soon.
Cheers!
Hi Troy,
There is a wealth of information on this forum and also the IGS database.
We are all trying to work things out clearly and concisely and many of us are learning and thanks to many forum members and contributors that accelerates our knowledge.
No I haven’t tried to clean the gems in question or even reoil them. The brown stains are within the stone fractures. I just don’t have that time or even the expertise to do any of that but thanks for the link. Perhaps I’ll just put those stones in question away for a rainy day. I don’t like playing with acids.
We are all busy like you say. I wish the best for you.
Mark
It is really blue. I wonder if it might be a Topaz
