Blue spinel - what to consider before buying?

[Mrs_Strizzle]

I also have a deep blue spinel in marble from the Hunza Valley in Pakistan that also fluoresces a pink-to-purple colour in LWUV, presumably due to some chromium. Apparently these spinels are also supposed to be cobalt-bearing but I haven't had mine analysed, Pic attached.

Yes, my blue spinel fluoresces lavender-pink. One day I will send to be tested for cobalt (though I know it's far from the idea cobalt color.

 

[T L]

Yes, fluoresces red, but has needles. My other blue and violet spinels do not fluoresce.

ETA: it also is red/pink under the Chelsea filter. Other blue spinels are not.

 

[Niel]

In my opinion, if they were good enough to identify this correctly they’d know it’s value.
Unless they’re asking $150- it’s overpriced.

 

[Bron357]

Unfortunately in most Pawn Shops / Estate Jewellers the assessment is done using a Presidium Gem tester. Great for sorting out CZ (glass) from everything else and telling a few other gems apart BUT lab grown sapphire and Spinel test EXACTLY the same as natural.
And mostly a Pawn Shop, wanting to make most money, will go to extra effort to test gems further ie lab report if they believe it is so and they can ask more.
Lab grown material is attractive and wears well, is often set in good quality settings and was very popular in cocktail rings ie big gems so without a reputable lab report assume lab and pay a price based on that.

 

[arkieb1]

Just because a "gemologist" or indeed a valuer writes a report on a stone and says it is "natural" doesn't mean it isn't a synthetic. I have lost count of items I have bought or attempted to buy that have had valuers and "gemologists" write reports or look at the item only to be proved wrong by a lab. Lots of refunds and clueless sellers and indeed people who both value items and have done basic gem grading courses that simply use Presidium testers and still cannot tell the difference between real and synthetic material later......

I'd be betting based on that one photo it's a synthetic.

 

[Avondale]

And mostly a Pawn Shop, wanting to make most money, will go to extra effort to test gems further ie lab report if they believe it is so and they can ask more.

They did test it further. And they are asking for more. If they were using only a presidium tester they most probably wouldn't have been able to identify the other spinel ring they have right now which is, in fact, listed as synthetic and thus sold for the price of the gold setting only. However, "trust but verify" applies to gemologists and labs as well, and the lab I would want to have the gem tested at is on a summer break until Thursday. Since I have no intention of spending money on a synthetic, it will be just a couple more days before I can get things moving. Otherwise I cannot rule out the possibility that the person the pawn shop is working with could've made a mistake.

If you have a UV light, you check the stone your self. Almost all flame fusion blue spinel under long wave UV light will be pink or red. Natural blue spinel will not have a reaction or look green. I tested all the rough lab blue spinel I have and this was true except for the pulled Czochralski material which showed a green reaction like a natural stone. Just make sure you have a long wave not short wave UV.

That's very useful, thank you! I'm not sure whether it's at all possible for the average consumer to acquire equipment emitting short wave UV as it's considered dangerous, but a 365nm torch is available.

 

[Avondale]

Ok folks, I know that speculating about synthetics is all the buzz, but as entertaining as it is, it isn't really useful to repeat things we already know. Here's a quick summary of what I've learned (both here and through research) that I didn't know, though, which hopefully will be useful to other people considering a purchase as well.


1. Distinguishing between natural and synthetic blue spinel

1.1. Fluorescence is a good starting point, but not always definitive. If the spinel fluoresces pink/red under long-wave uv light, there's high chance it's synthetic (the same applies for cobalt diffused stones). In natural spinels the presence of iron (which is lacking in synthetics and is what gives natural stones the desaturated grayish look) curbs fluorescence. It's still possible for natural stones with strong and pure blue colour to fluoresce. Labs can also test for short-wave uv light fluorescence.

1.2. Any decent lab with competent gemologists and the required basic equipment for a gem lab should be able to distinguish between natural and synthetic spinel. Flame fusion spinels have a distinct and different RI to natural stones, and synthetics produced by flux can be distinguished by observation of specific inclusions, fluorescence and spectrometer (specifically for blue spinels).


2. Treatments

2.1. Heating is uncommon, can be identified under a microscope by a trained eye and in cases of high heat also through spectroscopy.

2.2. Clarity enhancements can be identified under a microscope, additionally testing for oil is done using a hot point.

2.3. Cobalt diffusion produces strong and vibrant blue colour and is identified through observation using a chelsea filter, microscope, uv fluorescence and submerging in methylene iodide.


Here are a few extra articles for future reference:
Spinel and its Treatments: A Current Status Report - published in InColor
Oiled Spinel and Tanzanite - article by Lotus
GRS Alert: A new type of synthetic spinel appears at the Bangkok show
Flux-Grown Synthetic Red and Blue Spinels from Russia - article by GIA

Any additional information or amendment to the above is most welcome.

 

[fredflintstone]

Unfortunately in most Pawn Shops / Estate Jewellers the assessment is done using a Presidium Gem tester. Great for sorting out CZ (glass) from everything else and telling a few other gems apart BUT lab grown sapphire and Spinel test EXACTLY the same as natural.
And mostly a Pawn Shop, wanting to make most money, will go to extra effort to test gems further ie lab report if they believe it is so and they can ask more.
Lab grown material is attractive and wears well, is often set in good quality settings and was very popular in cocktail rings ie big gems so without a reputable lab report assume lab and pay a price based on that.

Yes, this may be true of some, but plenty have GIA Gemologist or other trained gemologists. So, I would not generalize. I used to sale to a lot of pawn/jewelry stores. Also knew many pawn shop owners who by experience could identify natural vs. synthetic gemstones with no problem.

 

[T L]

Ok folks, I know that speculating about synthetics is all the buzz, but as entertaining as it is, it isn't really useful to repeat things we already know. Here's a quick summary of what I've learned (both here and through research) that I didn't know, though, which hopefully will be useful to other people considering a purchase as well.


1. Distinguishing between natural and synthetic blue spinel

1.1. Fluorescence is a good starting point, but not always definitive. If the spinel fluoresces pink/red under long-wave uv light, there's high chance it's synthetic (the same applies for cobalt diffused stones). In natural spinels the presence of iron (which is lacking in synthetics and is what gives natural stones the desaturated grayish look) curbs fluorescence. It's still possible for natural stones with strong and pure blue colour to fluoresce. Labs can also test for short-wave uv light fluorescence.

1.2. Any decent lab with competent gemologists and the required basic equipment for a gem lab should be able to distinguish between natural and synthetic spinel. Flame fusion spinels have a distinct and different RI to natural stones, and synthetics produced by flux can be distinguished by observation of specific inclusions, fluorescence and spectrometer (specifically for blue spinels).


2. Treatments

2.1. Heating is uncommon, can be identified under a microscope by a trained eye and in cases of high heat also through spectroscopy.

2.2. Clarity enhancements can be identified under a microscope, additionally testing for oil is done using a hot point.

2.3. Cobalt diffusion produces strong and vibrant blue colour and is identified through observation using a chelsea filter, microscope, uv fluorescence and submerging in methylene iodide.


Here are a few extra articles for future reference:
Spinel and its Treatments: A Current Status Report - published in InColor
Oiled Spinel and Tanzanite - article by Lotus
GRS Alert: A new type of synthetic spinel appears at the Bangkok show
Flux-Grown Synthetic Red and Blue Spinels from Russia - article by GIA

Any additional information or amendment to the above is most welcome.

The only thing I would add is that I would look for inclusions like negative crystals and/or needles, but you kind of have to know what you’re looking at. That’s where a good gemologist comes in. And just because a gemstone has inclusions, that doesn’t mean that it’s natural or untreated.

I do like the use of the UV light though in this case.

 

[Niel]

It’s obvious by your remarks you’re annoyed that you’re not getting the answer you’d hoped.

 

[PrecisionGem]

That's very useful, thank you! I'm not sure whether it's at all possible for the average consumer to acquire equipment emitting short wave UV as it's considered dangerous, but a 365nm torch is available.

Here you go.

M101HO (High Output) - 11 Watt Shortwave & Longwave Ultraviolet Lamp K

The M101HO is our 11 watt shortwave field lamp. The longwave is a LED (365nm) UV flashlight. The Shortwave UV light source (254nm) is powered by a 11 watt shortwave UV fluorescent bulb. Longwave bulb AKA blacklight UV emitting at (365nm) Kit includes UV blocking safety glasses and 10...

www.uvtools.com

But you want to test it with long wave to see if it goes red, now short wave.

 

[Avondale]

The only thing I would add is that I would look for inclusions like negative crystals and/or needles, but you kind of have to know what you’re looking at. That’s where a good gemologist comes in. And just because a gemstone has inclusions, that doesn’t mean that it’s natural or untreated.

I do like the use of the UV light though in this case.

Yes, it's very reassuring that as long as you have competent professionals and a decent lab at your disposal, a spinel can be fully identified and thus purchased with a clean mind. It's not a case of "you need this large machine that costs $2 million that only a grand total of 4 labs in the world can afford to own", which can be very limiting.

Here you go.

M101HO (High Output) - 11 Watt Shortwave & Longwave Ultraviolet Lamp K

The M101HO is our 11 watt shortwave field lamp. The longwave is a LED (365nm) UV flashlight. The Shortwave UV light source (254nm) is powered by a 11 watt shortwave UV fluorescent bulb. Longwave bulb AKA blacklight UV emitting at (365nm) Kit includes UV blocking safety glasses and 10...

www.uvtools.com

But you want to test it with long wave to see if it goes red, now short wave.

Oh wow. I'm surprised this is sold freely, such equipment here is definitely restricted to professionals. I don't imagine myself being comfortable handling that, I don't even own any of the necessary protective equipment. Anyway, my torch is 365nm, right on the spot for long wave, so it will be perfectly adequate. I'll leave the short wave uv to the lab.

 

[Avondale]

It’s obvious by your remarks you’re annoyed that you’re not getting the answer you’d hoped.

On the contrary, I'm getting plenty of answers I hoped for. And no, I'm not annoyed, because I understand people are coming from a good place. But allow me to explain it so that there's no misunderstanding and hard feelings.

I opened this thread because I'm potentially interested in a stone and need to know what to be careful about, what to check, what to verify and whether I can verify it at all about said stone. This is what I asked about - information on the basis of which I can educate myself. I wasn't looking for verification that the stone is natural and that I'm okay to buy. The decision whether to buy or not will be mine, not the forum's.

The key here is that I'll be actively involved in the whole process. It won't be a matter of me, as a buyer, saying "get me a lab report or I'm not buying", and then blindly trusting said lab report. I understand that this is how most of the transactions of the average buyer work out and that mostly average buyers will ask for advice here. So it's expected that the answer they would get is "beware it might be synthetic" and "get a lab report".

But you see, I don't mean to just "get a lab report". Neither to just "buy a synthetic for a hundred bucks". What I mean is to be able to talk to the pawn shop and ask the right questions. I want to be able to talk to the lab and discuss the details of the testing they perform and the results of said testing. And for that particular goal "this stone is most probably synthetic" as an answer doesn't contribute anything.

What does contribute is information about the defining characteristics of the natural stone, the different lab alternatives that exist and their defining characteristics, as well as information about the known treatments and how they can be identified. And this information has been plentiful, and I've done my best to summarise it above so that it can be useful to others as well. I also had to steer the thread back into the direction I want it to go in. Turning this into a fest of "I think it's synthetic" answers is about as useful to anyone reading it as saying "the sky is blue" and it's not what I'm after.

 

[fredflintstone]

On the contrary, I'm getting plenty of answers I hoped for. And no, I'm not annoyed, because I understand people are coming from a good place. But allow me to explain it so that there's no misunderstanding and hard feelings.

I opened this thread because I'm potentially interested in a stone and need to know what to be careful about, what to check, what to verify and whether I can verify it at all about said stone. This is what I asked about - information on the basis of which I can educate myself. I wasn't looking for verification that the stone is natural and that I'm okay to buy. The decision whether to buy or not will be mine, not the forum's.

The key here is that I'll be actively involved in the whole process. It won't be a matter of me, as a buyer, saying "get me a lab report or I'm not buying", and then blindly trusting said lab report. I understand that this is how most of the transactions of the average buyer work out and that mostly average buyers will ask for advice here. So it's expected that the answer they would get is "beware it might be synthetic" and "get a lab report".

But you see, I don't mean to just "get a lab report". Neither to just "buy a synthetic for a hundred bucks". What I mean is to be able to talk to the pawn shop and ask the right questions. I want to be able to talk to the lab and discuss the details of the testing they perform and the results of said testing. And for that particular goal "this stone is most probably synthetic" as an answer doesn't contribute anything.

What does contribute is information about the defining characteristics of the natural stone, the different lab alternatives that exist and their defining characteristics, as well as information about the known treatments and how they can be identified. And this information has been plentiful, and I've done my best to summarise it above so that it can be useful to others as well. I also had to steer the thread back into the direction I want it to go in. Turning this into a fest of "I think it's synthetic" answers is about as useful to anyone reading it as saying "the sky is blue" and it's not what I'm after.

This article will answer your questions, though it is long and filled with a great amount of scientific information that will be foreign to the average layman.

https://www.gia.edu/doc/Flux-Grown-Synthetic-Red-and-Blue-Spinels-from-Russia.pdf

In all sincerity, many of the answers you received here are good. As you really do not know how qualified the pawn shop is to make the distinction between lab created vs. natural, you need to send the Spinel to a lab. There are many labs more than capable of determining whether the origin is natural or synthetic. This pawn shop can only give you any answer to the best of their knowledge, and we do not know what that is.

Buy it on the condition of sending it to a lab that it comes back as natural.

That is the best advice.

 

[Avondale]

This article will answer your questions, though it is long and filled with a great amount of scientific information that will be foreign to the average layman.

Heh, it’s actually one of the articles I quoted above. It’s not that difficult to read as long as you have some knowledge in chemistry and a bit in physics. The only thing that’s a bit more cumbersome is having to Google the names of unknown equipment. In any case it was very educational and also quite interesting to read.

Buy it on the condition of sending it to a lab that it comes back as natural.

The pawn shop offers lab certification prior to purchase. It was one of the first things I checked, I’ll have no issue to agree to buy it only on condition it comes back natural and untreated. But it was very useful to learn that fluorescence is more often than not a telling sign of synthetics. After all, why waste time with a lab if I’m 90% confident it will come back as lab grown.

 

[fredflintstone]

Heh, it’s actually one of the articles I quoted above. It’s not that difficult to read as long as you have some knowledge in chemistry and a bit in physics. The only thing that’s a bit more cumbersome is having to Google the names of unknown equipment. In any case it was very educational and also quite interesting to read.


The pawn shop offers lab certification prior to purchase. It was one of the first things I checked, I’ll have no issue to agree to buy it only on condition it comes back natural and untreated. But it was very useful to learn that fluorescence is more often than not a telling sign of synthetics. After all, why waste time with a lab if I’m 90% confident it will come back as lab grown.

What lab is that?

I've was in the gemstone business for 40 years, never had really any problems that were major with stones not being what they are represented as, but as the article stated, there is overlapping R.I. on some Russian synthetic Spinel with natural Spinel, and it is an old article.

All the best.

 

[fredflintstone]

Not here. The law requires a pawn shop to be only pawn shop. So only second hand pieces.

I agree, it’s most definitely somewhat grey, but to what extent I can’t determine by photos alone. In your experience, if we assume natural, what kind of treatments are common with these stones? Everyone says spinels are generally not treated, but then some obviously are…


GIA is not an option, as I already stated. It’s not $85 - not when you consider shipping half-way across the planet, insurance, import fees and VAT in both directions. No one is going to deal with all that just to potentially get confirmation the stone is synthetic. No one.

Didn't see this, sorry. Unless it is synthetic, Spinel's this color are untreated.

Pawn shop's sale jewelry. A good one will have a inhouse gemologist or a very experienced person that can tell what a stone is through experience.

I've not read through this whole thread. I take it your are considering purchase through the internet? Have you done business with this pawn shop before?

The mounting is suspect to a synthetic, but as I wrote earlier, jewelry stores have catalogs filled with generic settings, so that is not a tell all, but if it is 10k gold, be very afraid. Because if a person can afford a natural Spinel that size, they can afford 14k gold. But, then again, 15 years ago and more, these stones were not that expensive, but the ring looks in good shape to be that old or older, though maybe it just did not get worn much...

 

[PrecisionGem]

What is the asking price?

 

[Avondale]

What lab is that?

I’m not comfortable sharing that because it ties my general location to this nickname and I take great caution to preserve full anonymity whenever possible. I’m sorry, I know you’re trying to be helpful and I appreciate that. It’s a local small lab that has existed for about 30 years now.

I take it your are considering purchase through the internet?

Nah, the pawn shop is in my city. I can visit them anytime I want.

the ring looks in good shape to be that old or older

Ring is 14k but it isn’t in good shape. It’s been cut off from someone’s finger and was obviously pretty disfigured although they did their best to get it back in a circular shape. This probably contributed to the lower price.

What is the asking price?

It was offered for what was about the equivalent of $650-700, before the exchange rates skyrocketed recently. This might very well be no longer of any importance though, because the listing has been taken down. They might be updating it and it might reappear again in a couple of days (has happened before with other pieces) but if it doesn’t, then someone already bought it.

 

[fredflintstone]

So, you have seen it in person?

Of course, that is up to you not to name the lab, but I do not think you need worry about being targeted for robbery here or unwanted solicitations, after all, you are not using your real name.

 

[fredflintstone]

$650 to $700 would be about scrap gold price. Of course I do not know the gram weight of the ring, but to hold a stone of that size. Which means you'd be getting the Spinel for free, but if it is synthetic, it is not worth anything, anyway. If it is real, then you've done well, but you really are not giving us any real pertinent info. Also, shops without real colored gemstone experience often do not know the value of what they have.

Good luck to you.

 

[Avondale]

So, you have seen it in person?

Of course, that is up to you not to name the lab, but I do not think you need worry about being targeted for robbery here or unwanted solicitations, after all, you are not using your real name.

Was going to probably next week. If it’s sold, I won’t be able to. I’ll know soon, I guess.

I’m not concerned about robbery, I just know how easy it is if someone isn’t careful to be traced by what they post on the internet and I very much don’t like it, hence do everything I can to avoid it. You’d be surprised, especially with younger people, how one can start from a nickname and end up with full real name, address, names and addresses of family and friends. Shouldn’t be underestimated.

$650 to $700 would be about scrap gold price.

This is where difference in local economy comes into play. I don’t recall accurately but I’m pretty sure it was about six grams. If I could sell six grams of 14k gold for 600 dollars, I’d be able to buy a brand new car easily.

No. The scrap gold would’ve been no more than $100, at best, more likely about 80.

 

[fredflintstone]

Was going to probably next week. If it’s sold, I won’t be able to. I’ll know soon, I guess.

I’m not concerned about robbery, I just know how easy it is if someone isn’t careful to be traced by what they post on the internet and I very much don’t like it, hence do everything I can to avoid it. You’d be surprised, especially with younger people, how one can start from a nickname and end up with full real name, address, names and addresses of family and friends. Shouldn’t be underestimated.


This is where difference in local economy comes into play. I don’t recall accurately but I’m pretty sure it was about six grams. If I could sell six grams of 14k gold for 600 dollars, I’d be able to buy a brand new car easily.

No. The scrap gold would’ve been no more than $100, at best, more likely about 80.

I'm talking retail scrap. Big difference in price, What you pay for is a lot more than the jewelry trade does. What you get paid for is much less.

 

[Avondale]

I'm talking retail scrap. Big difference in price, What you pay for is a lot more than the jewelry trade does. What you get paid for is much less.

You got me curious and I’ll make sure to ask my jeweller what’s the retail scrap price that he can get but I’m not gonna lie - I’ll be very very very surprised if it was anything even close to $100 per gram provided last year I was buying brand new custom pieces for half that price.

 

[fredflintstone]

You got me curious and I’ll make sure to ask my jeweller what’s the retail scrap price that he can get but I’m not gonna lie - I’ll be very very very surprised if it was anything even close to $100 per gram provided last year I was buying brand new custom pieces for half that price.

Good luck, most won't tell. They do one of two things, sale it to a smelter who only deals with retail, or melt themselves if they have a bench jeweler and make a new ring.

 

[fredflintstone]

Just at gold prices today for the consumer investing (not speaking of retail mark up), 6 grams of 14k gold is $195.14.

 

[fredflintstone]

"The average markup at GoldSilver.com stands at roughly 35%, said company president Alex Daley. Markups for gold jewelry on eBay EBAY, 3.04% and retail stores vary widely, with premiums anywhere from double to three times or more over the metal’s value."

3 golden rules for buying jewelry you can wear — and resell at a profit

With a few exceptions for certain coins and bullion, the IRS considers metals and gems to be collectibles.

www.marketwatch.com

 

[ItsMainelyYou]

I’m not comfortable sharing that because it ties my general location to this nickname and I take great caution to preserve full anonymity whenever possible. I’m sorry, I know you’re trying to be helpful and I appreciate that. It’s a local small lab that has existed for about 30 years now.


Nah, the pawn shop is in my city. I can visit them anytime I want.


Ring is 14k but it isn’t in good shape. It’s been cut off from someone’s finger and was obviously pretty disfigured although they did their best to get it back in a circular shape. This probably contributed to the lower price.


It was offered for what was about the equivalent of $650-700, before the exchange rates skyrocketed recently. This might very well be no longer of any importance though, because the listing has been taken down. They might be updating it and it might reappear again in a couple of days (has happened before with other pieces) but if it doesn’t, then someone already bought it.

I hope I'm wrong- but my gut is pinging and I'd feel bad not saying anything.
Of course, you don't have to take my advice and I only mean to give it in good faith- not to discourage.

That's a red flag one right there:
The price doesn't make any sense. Not even if bought at the source.
That price alone makes me think they knew it was synthetic and overpriced it for what it was hoping someone would hopeful bite without making sure the agreement was in place to return/reimburse after lab check. There is almost zero chance of a retail/pawn shop worth their salt mistakenly selling a rare real specimen like this. Not for at least a decade.

*A decade ago I bought a imperfectly cut 5 carat natural blue spinel in a custom 18k pink rose gold diamond mount at auction- it had a full GIA lab report.

If they had any inkling it was the real deal, sending it off for a full report would have happened the day they got it as a matter of course. They're not ignorant of trends or turning a profit. Not in the internet age. It's chump change if the spinel is real and would be an expected requirement in order to sell.

Red flag two:
The color range was the most popular synthetic spinel color for several decades after red. Spinels in desirable colors can be 100x rarer than ruby or sapphire. Yes, you read that right. That's why naturals never became 'popular'- there just weren't enough to make them commercially viable.
Most people have never even seen a natural one.
They only know them as synthetics from class/fashion rings. There are many synthetics out there.

It is my favorite gem and the only one I collect.

Usually, if a spinel ring is missed as natural over a carat (spinels are more 'commonly' found in the sub 2 carat range) it's because it was inherited or a private owned piece sold ignorant of it's actual value.
So, if buying with expectation of real- they refund the cost of ring/lab if it comes back synth. If in the very slight chance it turns out to be real, it will have to be full lab certed for insurance in any event, the money won't be wasted either way.

I would be over the moon happy for you is it turned out as real- but don't trust anything until verified- a stone like that has paperwork- always.

 

[Mrsz1ppy]

This topic has fascinated me because I bought a blue ‘spinel’ from TRR last week. I ordered the light @PrecisionGem posted, and can’t wait to check my find. Apologies to OP, but this was just too much of a coincidence not to hop on your thread.

 

[T L]

I have never seen, or remembered seeing, a natural blue or violet spinel in that size, 4+ carats, ever cut in a round. Has anyone else?

My memory is either fading, or that’s a red flag. I could be wrong, but I’ve been collecting these spinels for years. Someone please let me know if I’m wrong.