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Fakes & Fraudshow to tell if a gemstone is synthetic? I am so confused!
1st Feb 2008 04:06 UTCFira Shay
I admit I am not a gemstone expert but I can in most cases tell by looking, what exactly I am looking at. I have watched many jewelry/gemstone home-shopping channels. One of them is JTV. I watched it for almost two months. I have seen them sell synthetic Alexandrite, which I'm not interested in even if it were real because I know this stone is said to posess a very dark aura. It's been labeled as the "gem of widows" meaning that if I was to own it I'd likely lose a husband or never get married at all. Some supersticious crap, which I'm sure doesn't matter to gemologists. But just in case, I stay as far away from it as possible.
Anyway it is interesting to hear presenters go on and on about this stone from an educational point. But one thing that really got me thinking is what one presenter stated about these synthetic gems. Acording to him if you take it to a gemologist, and have the stone tested, the results will be that this is Alexandrite...not a synthetic. So, they are practically claiming that as long as the only person who knows that it didn't come from the ground is you, you can sell it as a natural stone and NO ONE will be able to tell the difference.
HOW ON EARTH do you tell that it's a synthetic then? If all the properties are EXACTLY the same, even under close and extensive examinations, what makes it different from the real? Is there something they are just not mentioning? Does it really test out to be a natural Alexandrite gemstone?
And another question I have is about the gemstone jewelry sold on Gems TV, another jewelry shopping network. They claim that all of their gemstones are natural but I've been reading some nasty comments online from UK customers (where this network originally started) some claming that their gemstones tested out to be synthetic. And once tested, the customers weren't able to return because the third party, a gemologist, got involved. Which implies that a gemologist may have switched the stone while examining it, and said it was fake or something along those lines. And again, I ask myself, how can I tell if the gemstones are real or not? Can anyone really tell a difference between a good synthetic and the real deal? And how do I know if the ring with a ruby I bought (which appears genuine to me just not of best quality) has a real ruby?
In fact it doesn't matter where I go to buy my jewelry, I wouldn't know a way of telling. I could walk into Bvlgary and walk out with a synthetic gemstone ring, having paid thousands of dollars for it, then take it to a gemologist or an appraiser and if it tests genuine I'd be satisfied. And it's supposed to test as genuine according to JTV presenters.
I am SOOOOO confused now! I don't think I believe in gemstones being genuine anymore, unless I am the one who mines them straight out of the earth, cuts them, and sets them in jewelry myself.
Is everything sold on the market today, labeled as "genuine", good fakes/lab grown synthetics? And the ones labled as "fake" just bad lab experiments which didn't turn out right and don't imitate the stones enough?
Any thoughts and comments will be appreciated.
1st Feb 2008 09:36 UTCFira Shay
I recently bought a 3 carat emerald that cost me $300.00 per carat. It was advertised as natural "comming from the earth" but if it honestly were, I would have gone broke trying to pay for it. It would have been worth ten times more. The reason?
It's more then likely synthetic, lab created. Sure it has the exact physical and visual properties and will test exactly as an Emerald until they find the better equipment to distinguish a man made clone from the one that came from the ground, but for now it's an Emerald. The thing to keep in mind however, the more of them get created, the lesser the value will be years from now where as the one that comes from the ground will continue to go up in price.
What I don't understand however is how these home shopping tv networks even dare advertise it as comming from the earth and keep telling tales of mining these stones when the only mines they use is a lab around the corner. The price of the stone does go well with the prices for lab created, synthetics, so why put on a show? Just tell people straight out "these stones are lab created which doesn't make them worse then natural but does make them less expensive. Not like we charge a lot for them anyway, just the price of a true synthetic." It would make everything much more clear and people could make a well informed decision!
I have found this article online and I'll post a link if you want to read about lab created, synthetic diamonds. Here is where JTV and all those others come in. Are any of their diamonds actually formed in nature? OH PLEASE!!! If they were, they'd cost thousands upon thousands even for the smallest insignificant specks! In fact any "gemstone" you see selling for 10% or less of what it would cost, is 99% of times a synthetic, lab created stone. If it weren't you wouldn't be able to afford it.
http://www.wired.com/wired/archive/11.09/diamond.html
I used to be facinated by a gemstone world now I am just disapointed and disgusted because of mislabling and lies. Someone needs to start telling the truth.
Would I still buy a 3 carat Emerald if I knew that it was an exact clone to a nature's Emerald only I wouldn't be able to afford the one from nature and here I was getting quite a deal? I probably still would but at least I'd know right away that it was not a nature's creation. Which means that nothing's rare about it.
Which brings me to storngly question the nature of Tanzanite now. Maybe the Tiffany's really did find 100 or so pieces of Tanzanite in the earth originally and priced it accordingly but what if the Tanzanite that all these companies sell nowdays, is actually produced around the corner in a lab? Why am I paying a $1,000 per carat for something that was likely grown in a lab?
And I doubt that Tanzania would to this day be such a poor country if their earth was stuffed with all these natural, rare and exotic gemstones.
So, it's all a myth. Real gemstones are a thing of the past. If you're lucky enough to inherit a piece of jewelry with gemstones from your great grandmother, which has been in the family for ages, then and only then, do you have the real, exotic and priceless gemstone peice. Back in those days, they didn't have the technology to create synthetics.
Having said all that, please be careful with your money. Invest wisely.
1st Feb 2008 15:05 UTCsteven garza
Your guidelines, under regular circumstances of the average buyer, are good; but, if you go to a show, you'll find that the REAL stones ARE only a pitance, in comparison to the jewelry stores, which would make you think ALL the stones are fake, which they aren't! You'll find MUCH better quality & better SERVICE at shows than ANY "kiss-your-butt-to-make-a-sale" store will do, which tends to be "soothing" more than truly informative. You should hear the carp I hear, when I'm in the mood to have fun, at their expense.
Next, why would you WANT to buy something from people who refuse to allow an appraisal? Using the same excuse for refusing a return, over & over again? Unless they can PROVE a stone was switched, (underline this) 20 TIMES IN A ROW, they MUST take it back; the goods are sold under fraudulent grounds & ANY district attorney would LOVE such a case! The JTV would fall over BACKWARDS to settle, just to kill possible bad PR, which this case would surely bring.
Hope this helps.
Your friend, Steve
1st Feb 2008 16:25 UTCMike Salotti
4th Feb 2008 13:54 UTCSteven Thomas
One more note there are a lot of books available ,I have spent quite a lot of cash on mine, many are cheap but with accurate photo's and information. to learn these things,there worth it if this is a hobby or business someone wishes to persue, I sincerely hope this may shed some light on the confusion,If I can help send me an E-mail.
Ps. I can always send sa some photos of inclusions in any stone for you compiled from a da base of these inclusions in natural and synthetic.Steve
4th Feb 2008 15:58 UTCRay Ladbury
As long as there have been objects of desire, there have been those who were willing counterfeit said objects. In the gemstone world, you have two types of artificial stones--simulants, which are not even the same mineral as the stone they imitate--and synthetics, which are at least chemically the same mineral, but man-made. Actually, the world of simulants and synthetics is fascinating in its own right, but most people want a "natural" gemstone. Even here, you run into gemstones that have been "treated" to improve their appearance: Tourmalines, imperial topaz, sapphires and many other gems are heated are routinely heated; some sapphires have light, small elements like beryllium diffused into their crystalline structure to give beautiful colors; topaz is often irradiated; emeralds often are treated with resins or fillers to hide cracks and so on.
All I can say is that all of these treatments leave marks and can be detected by very good, knowledgeable gemologists--or by you if you have sufficient knowledge, familiarity with gems and their treatment and at least some gemological instruments. Likewise, natural gems can almost always be distinguished from simulants and synthetics--usually by looking at their microscopic inclusions. Gobelin had this down to an art, literally. He had a wonderful book of photographs of gemstone inclusions that was a work of art in and of itself.
What it all comes down to is that either you need to buy from a knowledgeable and trusted source or you yourself need to become knowledgeable. I have often noticed that as soon as I start asking questions, the frauds start to steer clear of me. And yes, sometimes you will get taken. Learn from it and don't make the same mistake twice. Gemstones represent an amazing world of beauty. Don't let yourself be put off by the bad apples. Just learn to protect yourself--and this website is a good place to start learning.
22nd Feb 2008 14:53 UTCzada
24th Feb 2008 07:19 UTCCurtis Wilbur Expert
Another tact is to buy material direct from the miner, (which is possible in many places in the world.) I happen to be in San Diego, which is close to some of the most productive tourmaline, beryl, kunzite, and gem garnet producing areas in the world. There are a number of people that the miners can recommend to cut your stone, and it makes the ownership of a gem so much more interesting when you know exactly where it came from.
And although I hesitate to cut some of these beautiful natural stones, I did have a 3.5 carat rubellite cut and mounted for my wife.
P.S. Another thought on this subject. When people are in a hurry to make money, they make mistakes. One of the most common mistakes is a bad cutting job, which manifests itself with facets of different sizes and uneven brilliance. I've seen natural aquamarine displayed on a cruise (naturally I took my loupe with me, and you should have seen the people crowd around when I took it out to look at these stones) which was so badly cut, that I couldn't recommend the stones to anyone.
Contrary to being disappointed, I find this aspect of human nature to add a fascinating complication to the challenge of finding a great stone. Do not despair!
11th Mar 2008 10:07 UTCClaire Scheepers
19th Mar 2008 12:22 UTCRay Hill Expert
19th Apr 2008 23:57 UTCConnie
20th Apr 2008 00:44 UTCDavid Von Bargen Manager
15th Jun 2008 04:15 UTCDianna
15th Jun 2008 04:52 UTCRay Ladbury
10th Jul 2008 21:13 UTCGrace Webster
-------------------------------------------------------
> End run, get a reputable appraiser {FGA or GG/GIA>
> to test any stone or stones in jewellery or out,
> that you need confirmation on. The industry is
> vainly trying its best to keep up with all the
> treatments on Natural stones, let alone the
> synthetics that are grown in pressure bombs that
> have 3 phase inclusions. Testing is the answer,
> believe me. Don't let yourself worry unnecessarily
> when a reasonable investment in a good appraiser
> with up to date equipment and training will give
> you relief and confidence in your purchases.
GIA does not appraise diamonds they only grade them.
17th May 2009 16:23 UTCTerri Goselin
29th May 2009 05:26 UTCJamey Swisher
These TV shows often sell stones under the wrong ID and or heavily treated as non-treated gemstones. JTV even sells glass filled topaz for crying out loud, got one in a parcel I bought to test(and of course sent right back, lol). Much of it is glass filled, resin filled, epoxy filled, etc.
A properly trained gemologist can ID a synthetic from a natural with nothing more then a microscope, and possibly a Spectroscope included in there for some stones. The only synthetic that can not be ID'ed under good magnification and key inclusions or growth structures is Quartz. They have so well perfected hydrothermal quartz, that is very few cases, can one tell the difference between natural and synthetic without the use of expensive lab equipment, like a RAMAN. You have to be lucky and hope that if natural, it has a natural inclusion in it or if synthetic that it just happens to have either a seed plate or a tell tale trail of breadcrumbs, otherwise no go without the heavy tools.
But syn. corundum(rubies & sapphires), emeralds and other beryls, spinels, etc. All have tell tale inclusions and/or growth patterns to look for if the person knows what they are looking for!!
Many of these TV shows are selling mined from the earth gemstones. They are just heavily treated, which is what brings the costs down so far. In most instances, where people think they are getting a deal, they are actually getting robbed blind, because the stone being sold is not worth anywhere near what the TV show is even selling it for! We just tested an Emerald for a client the other week, Columbian... no treatments mentioned... natural gemstone... top quality.... the stone was more epoxy(read GLUE) then it was beryl!!!! That is a newer treatment in Emeralds now, they are using epoxies and super glues to fill the cavities, fissures, etc. These glass filled/fissure filled rubies are actually more glass then anything! They should actually be no longer called natural stones, but instead, be classified as a composite stone! I just saw a test where they took true glass filled rubies(the good ones) and many of these TV show and Ebay sellers fissure filled/glass filled rubies and put them in acid to dissolve the glass. The TV shows and Ebay sellers stones where lots of little pieces of material that had been "glued" back together to form one stone using the majority of glass! The true, properly done, glass filled rubies just had cavities where the glass dissolved still leaving one solid stone for the most part, which is the proper use of this treatment.
The cookers in Thailand are even getting so good they are finding ways to introduce natural looking inclusions into synthetic rubies and sapphires to fool the untrained eye! Some of them are quite convincing too!
On another forum two different people got synthetic stones in the supposed all natural no synthetics JTV gemstone parcels! One of which was nothing more then glass, or Zandrite as they call it, but in reality it is nothing more then a type of glass.
Your best bet is to shop with legitimate stores/dealers. Shopping off of TV and/or Ebay is like playing Russian Roulette to be honest. Or as suggested by someone earlier in the thread, buy direct from a miner that is close to you or something. If shopping on Ebay, avoid the Chinese and almost all the Thai sellers, just for starters. There is an ongoing and growing list over at http://www.gemaddicts.com of bad sellers and good sellers and those somewhere in between. It would be a good starting point to find some legit vendors, or at the very least, finding some to stay clear of!
FYI, it would be a huge help for anyone/everyone to submit Vendors over there as well for Review for good ones and bad ones. There is a form to do so. It would greatly help the entire gemstone/mineral/gemological/geological communities as a whole to get the lists growing! :).
But have no worries, there are real and completely natural gemstones out there, just don;t expect to pay .99 cents for them, hehe. Seriously though, they are out there. Also, don;t be afraid of some treatments, especially those actually accepted by the Industry, i.e. heating of corundum, heating of tourmaline, glass filing of rubies(the proper way), flux healing, stabilization of turquoise, Andamooka opal, Tanzanite, citrine, prasiolite, etc. Just remember that in most cases a treated stone should always be cheaper then its untreated counterpart, but that is not always the case with like tourmaline heated vs. non-heated typically no difference in price. As long as the treatment is permanent and relatively(meaning glass filled) to permanently stable, no need to worry.
lastly, don;t fool for the synthetic diamond BS many are trying to pull now!!! There are synthetic diamonds being grown now using HPHT and CVD methods by 5 different companies, but they are all just as expensive as their natural counterparts for the most part!! What you are seeing being sold cheaply as man-made diamonds are nothing more then cheap commercially produced CZs. Like nexus Labs, who sells nothing more the Signity branded CZs, or at least that is what they were doing last year, but they are at least selling them as simulants now instead of synthetics!
2nd Jun 2009 20:35 UTCPeter Lyckberg Expert
Then the three books on inclusions in gemstones by Gubelin, Koivola are great!
11th Jun 2009 20:25 UTCTim Jokela Jr
Any sort of treatment of gemstones must be disclosed by the seller, this is a law in the US and Canada at least.
2) DO NOT buy gems advertised on television.
3) Do not assume that gems you bought at the mine actually came from that mine.
4) Educate yourself. It's fun, and at cocktail parties you'll be able to tell people that in fact all emeralds are oiled, sapphires are all heat treated, tanzanite and alexandrite are in fact not even proper mineral names, and that garnet is actually a group of over a dozen different minerals, found in every color of the rainbow, not just red. Buy books. Read them. Take a GIA course even. Mineralogy is a fascinating subject... look into it and you'll have a hobby that will last you a lifetime.
5) Remain healthily skeptical. When you buy a nice stone for $900, try not to worry about whether you've been scammed; try to enjoy it's beauty. Bearing in mind that there's a billion people out there living on a dollar a day will help distract you from your worries.
13th Jun 2009 01:51 UTCJamey Swisher
This is just NOT correct. All emeralds are not oiled, although many are, but not all. Also not all sapphires are heat treated. Not sure where you got this information but it is entirely incorrect. There are many lab reports out there proving that those statements are just not correct.
While the majority of all emeralds sold currently are oiled and most all sapphires are either heat treated or diffusion treated, they are not all treated and there are plenty of untreated ones out there, but expect to pay a premium price for them.
18th Jun 2009 20:37 UTCTim Jokela Jr
99% of emeralds are oiled, and 99% of sapphires are treated.
Sorry for exaggerating.
19th Jun 2009 04:56 UTCJamey Swisher
6th Dec 2009 05:12 UTCblondie
31st Jan 2010 08:49 UTCAnonymous User
You can tell in Aquas because they are replaced on the market with Spinell and the spec. gravity (density) if far smaller than that of Spinell.Just take the dimensiuns and keeping in mind how the stone is cut (there are a few sites were you can aprox. compute a stones volume based on cut and dimensions) you can calculate the spec. gravity and than compare it to that of the supposed aqua.:)
11th Feb 2010 13:12 UTCAlejandro G. Aragón
I've always been interested in gemology and I'd like to know more about distinguishing fake from real gemstones since I've become a potential buyer. Could you please recommend me some trustworthy and useful literature/bibliography on this issue? Thank you very much from Spain
Alejandro (nimrod_brandnew@hotmail.com)
2nd Mar 2010 17:08 UTCAlexandra Catalina Seclaman
If you want to make the difference between a real crystal, made by a geological process and a lab made one you will have to understand that mineral.
Understanding not knowing makes a good scientist.
Ups almost forgot... and a keen eye... and passion.
PS: Didn't want to offend anyone, just stating my point of view.
23rd Jun 2010 19:59 UTCMiya
hello! I am currently traveling the Middle East. I recently bought a Topaz here, from what seemed to be a very reputable jewelry store. The old man seemed very wise and assured me that the Topaz is real. Hence, I got it made into a ring. The topaz is cut into a traditional "diamond shape"..it is VERY brilliant, sparkles like crazy and the cuts are are sharp and perfect. I cannot see any imperfections in it (although I have just looked with the naked eye)...it is a gold-orange-slightly brownish color..I believe its an Imperial Topaz. Now, I took the seller's word that it was real, but I am now having serious doubts! What if it is glass??? How can I tell if it is heat treated, or even a topaz at all?! (What if it is citrine?!)
Please, I really need your help. I actually bought this for myself as an early birthday present. My birthday is in November and Topaz is my birthstone. I'm going to be 20 this year!
Really hope to hear from you...thank you so much for reading!
PS: if there is anyone else here who can help I will be forever grateful!!
23rd Jun 2010 20:49 UTCRob Woodside 🌟 Manager
24th Jun 2010 06:19 UTCJamey Swisher
Right now in the Middle East there are thousands upon thousands of fakes being pushed everywhere to part unsuspecting and unknowing soldiers and the like from their hard earned $$$$$, so you most definitely should have it checked out ASAP.
24th Jun 2010 18:13 UTCMiya
Thank you so much for your fast responses!!! Yes I will have the topaz checked immediately....just have to find a reliable gemologist. The whole reason I bought the stone is because its (hopefully!) real. ((Hahah I guess you can say I sort of *do* believe in its metaphysical properties.)) I believed the jewelers' claims it was real, but......umm...you never know.
Rob, thankyou for informing me about the RI index...that can definitely tell whether or not it actually is topaz...and Jamie thanks so much for letting me know about the vast number of fakes on the market...I'm going to be a lot more cautious in the future.
Lastly, the thing that heightens my suspicions is the fact that the jeweler didn't sell me the topaz for a very high price...it was in fact very inexpensive! He said that Topaz (here, at least) is not a precious stone AT ALL and is almost always found very easily. He said the Topazes here come straight from Pakistan and Afghanistan, and there is not a very high demand for them....so, basically put, its a "cheap stone."
What do you think? :S eeep..
26th Jun 2010 04:50 UTCJamey Swisher
Last I checked any kind of Imperial or Precious Topaz has a pretty good demand, especially the pinks from Katalang(sp). So I am not so sure I "buy" that line from him.
26th Jul 2010 22:12 UTCPaolo Malesci
28th Jul 2010 03:40 UTCJamey Swisher
-------------------------------------------------------
> Topaz may be a very cheap stone, once I have payed
> a stock of little and not clear xls R$20 (11-12
> US$ !). Obviously gem quality imperial topaz is
> more expensive but prices are not very high in
> mining countries.
Normal topaz, no, prices are not high, but imperial and precious topaz carries a hefty price tag in most any case, especially the ones in Pakistan from the aforementioned mine.
23rd Jan 2011 21:18 UTCRuthAnne Hiott
23rd Jan 2011 21:31 UTCAdam Kelly
But finding something yourself is worth more than any amount of money, at least for me.
27th Jan 2011 22:52 UTCAnonymous User
If you spend over a certian amount on any given stone I would always get a lab report. If it's a CS stone I would recommend AGL if a diamond then GIA
9th Feb 2011 04:18 UTCJamey Swisher
Another good lab to use, if you do not have the money to send to a big full blown one, for colored gemstones, would be Stone Group Labs. They do an excellent job and are not quite as expensive as the bigger labs.
9th Feb 2011 05:08 UTCAnonymous User
Stone Group Labs? Will have to look into them. Thanks for the reference
9th Feb 2011 05:17 UTCJamey Swisher
4th Apr 2011 19:58 UTCJustin Mayet
-------------------------------------------------------
> Hi there. -I am an accredited jewelry
> professional (GIA) with a degree in Geology and
> mineralogy and have been doing research on (and
> selling) gemstones from Tanzania for several
> years. Just in the last stages of completing my
> Graduate Gemologist Diploma. - One CAN distinguish
> between natural and synthetic stones - even
> diamonds. The way in which synthetic stones are
> "grown" is different and there are microscopic
> differences that any good gemologist should be
> able to see. - Laboratory grown stones are worth a
> fraction of natural gems, but the microscope will
> reveal the difference!
could you please e-mail me and let me know where you get your authentic stones from. oldschoolblue89@yahoo.com
Thank You,
20th May 2011 15:35 UTCDave Hall, Out of Creation Jewelry
Thank you, Steve,
Dave Hall
20th May 2011 16:03 UTCJolyon Ralph Founder
Look at gemmology training from the likes of the GemA (The FGA courses) or the GIA. Courses and examinations are not cheap, but then this is your profession and to be honest, it's kind of an absolute minimum for the trade these days.
Jolyon
21st May 2011 05:28 UTCJamey Swisher
25th Jul 2012 23:27 UTCYoanna
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=251075772101
26th Jul 2012 02:01 UTCReiner Mielke Expert
26th Jul 2012 08:33 UTCAnonymous User
26th Jul 2012 09:41 UTCMarcel Schwedler
good luck
26th Jul 2012 12:09 UTCOwen Lewis
To begin at the beginning.....
Synthetic gems crystals are real. They have the same chemistry in the same crystal lattice as the same compounds that crystalise in the Earth. The more obvious differences are that:
- Naturally formed crystals form over very long periods - and, often, formed a very long time ago. On the other hand, depending on the process, synthesising a coloured gem crystal in the lab takes somewhere between a few hours and about a year, depending on the process used and the size of the crystal grown
- Chemical and physical processes occurring in the Earth are not only slow, they are chaotic in occurrence and haphazard in production. Formation in a laboratory is not only quicker but it is cleaner.
So why are 'natural' gems prized (priced) so much higher than synthetic gems of the same type. The answer is history. Because of the the Earth's dirty, chaotic lab, the vast majority of crystals are not fit (are not beautiful enough) to be considered as gems and worn or carried as beauteous symbols of wealth. Those that are, are rare and have throughout human history been sought after and traded as items of value. Synthetic gemstones can be just as beauteous and with all the physical properties of the naturally formed gemstone - but they can never be rare (though some are collector's pieces in themselves). Synthetic gemstones can be made according to demand and in unlimited quantity.
It is never easy to tell with certainty a synthetic from a natural once the stone has been cut but, with experience and the right instruments, it can be done to a high level of assurance. Few gem owners and even small jewellers are trained and equipped to do this. with a high degree of certainty. The instruments required are expensive - more so than most gems - and themselves require skill to use.
For the average buyer of low-medium priced gemstones, the guideline should be 'caution' - if it looks much too good for the money being asked then, if its not a fake (a simulant) then it's probably wise not to buy it (if you care about it having formed in the Earth). Buyers of high-priced gems have the option to have the the stones certified by a gemmologist before purchasing. N.B. A simple certification of a stone's natural origin does not assure its value. Valuation/appraisal is a separate exercise, requiring additional knowledge of the gem market.
All the main gem varieties are commonly produced synthetically, including, Diamond, Ruby, Emerald, Sapphire, Amethyst, Citrine, Alexandrite - and so list goes on. Not all gem varieties are synthesised but the limits are commercial rather then scientific. The commercial production of synthetic gems has sometimes been carried along on the back of their synthesisation for industrial use e.g. Diamond and Quartz (Amethyst, Citrine etc). Other synthetics, in particular Ruby, which was first produced synthetically over 110 years ago, were iaimed at the gemstone market from the very outset. The very first synthetic rubies were sold simple as particularly fine quality Ruby from an undisclosed location for some while.
Synthetics and simulants are so important in the gem world that I think that a study of them should be made by every serious gem collector or trader. They are a fascination in themselves and it is a real pleasure to develop the skills to be able to distinguish them from gemstones formed in the Earth. This can be done only at the most basic level by studying books. One then needs also to spend many hours examining as many synthetic gem types and specimens as one can to build a little collection of them for reference, learning how to tease a confession out of them.
A point worth remembering, I think, is that it is often relatively simple to conclude with certainty that a stone has a natural origin. It is frequently harder to be quite certain that a specimen is of synthetic origin. The more perfect the specimen, the more care is needed.
26th Jul 2012 12:53 UTCRock Currier Expert
The stone is not very large. Ask the supplier how many carats the stone is. It sounds like you would be paying a lot more for the ring than the stone. What metal is the ring made from? and how much metal is in the ring? There is a lot of amethyst in the world and stones like that are fairly cheap. There is no way to know if it is a natural stone or not without testing, which will cost you the better part of $100, probably more than the stone is worth. When the testing cost more than a natural stone is worth, no one cares if it is real or not because it cost more to find out that what the stone is worth. Ask the supplier if he will also refund the cost of your getting it tested if it turns out to be man made.
26th Jul 2012 14:26 UTCAnonymous User
Do they make synthetic amethyst?
26th Jul 2012 15:37 UTCAlfredo Petrov Manager
26th Jul 2012 16:30 UTCSpencer Ivan Mather
26th Jul 2012 17:16 UTCOwen Lewis
-------------------------------------------------------
> Yes, there is synthetic amethyst from Russia.
> Since natural amethyst is cheap and abundant, I
> wonder why anyone would bother synthesizing it,
> but they do.
From China too. Some pieces are very attractive. I suspect that the synthetic Amethyst and Citrine production got started on the back of the synthetic Quartz industry which got started in the early 1940's and increased to become a major industry in support of the spread of electronics using crystal controlled oscillators as an accurate time source. If you've mega-investment in the industrial plant to provide oscillator crystals, then the doping of some Quartz to be Amethyst (etc) is nearly cost-free.
Top quality synthetic Amethyst can actually be more expensive than much of the natural stuff.
26th Jul 2012 17:49 UTCOwen Lewis
-------------------------------------------------------
> That is better. ;). Because, I have around 40 or
> so unheated sapphires of varying colors(including
> a color change) sitting here in front of me right
> now from various locations around the world but
> mainly from Africa, Burma, and Australia(although
> you could consider ALL sapphires from Australia
> heated under their current weather
> conditions..lol), hehe. ;).
Quite right Jamey. I have some untreated Emeralds and Sapphires (all sourced pre-1980's). It may depend on the way (and when) the stones entered the selling chain. I know of one gem trader in Brazil who is on the record as saying that he has only been offered one untreated Emerald in the last three years.
Heating lower grade Sapphire to improve its clarity and colour is so old a practice (2,000 years?) it is hard to object to it. Rather, one should just know enough to know that this is this and that is that - and the market values the two differently. Have you ever seen a cut and finished Montana Sapphire that has not been heat treated? Tanzanite is another lovely stone where virtually all the output is heat-treated. Those few who have seen an untreated cut and faceted Tanzanite will know why (only very rarely do such pieces look other then sad).
The trade accepts oiled Emeralds - and so do customers - without penalty except in the very top grades.This again is a practice at least as old as the Spanish exploitation of the Columbialn mines and domination of the world trade for a while. I think there is a fair distinction between this and the resin resin filling of Emerald which is otherwise so structurally flawed as to likely fall apart if subjected to the stresses of cutting without this prior treatment. Only in the very top grades are there Emeralds of that very rare quality where their appearance could not be improved by oiling. Those who get to see low-medium grade untreated Emeralds can attest to this - and the wonder that judicious oiling can work.
26th Jul 2012 18:35 UTCAlfredo Petrov Manager
26th Jul 2012 20:30 UTCSpencer Ivan Mather
26th Jul 2012 21:01 UTCPaul Siegel 🌟
Paul
26th Jul 2012 21:35 UTCRock Currier Expert
27th Jul 2012 13:36 UTCOwen Lewis
-------------------------------------------------------
> .... If I
> see a cut gem with a liquid+gas inclusion, I would
> assume it has not been heat-treated, as I imagine
> any severe heating would cause it to expand and
> crack (although I don't know whether this is
> really the case or not - might only be true for
> large bubbles?). However, if a corundum or a
> tanzanite or other gem does not include such
> bubbles, how could one tell whether they've been
> heated or not? I would assume that all have been
> heated, unless there was proof to the contrary,
> and I don't know what physical tests could prove
> that. (i would require something more substantial
> than just the word of a seller, regardless of that
> person's public reputation, because I doubt any
> sellers have been present for the entire
> production chain from mine to show floor.)
We can start from the fact that all crystals have been heated. Crystal formation is a hot process. Some crystal have, as a freak of nature, been heated more than once. So what an examiner is looking for is subtle signs that the effects being observed result from very brief heating as opposed to heating and cooling applied on a geologically significant time scale. In such cases, there is most often a partial healing process that follows on from the damage. Where this healing can be identified, it's good evidence that the damage had a geological rather than anthropogenic cause. This can sometimes be done with just a loupe and a directed light source but a good microscope is really the tool for the job.
Here's a set of pics to illustrate what I mean. The stone is a light-yellow Danburite which, unusually, has been cut and faceted into a 9mm round, making an attractive feature of some non-surface reaching tubes within it. If the first shot is zoomed, then close to the girdle at one 'oclock can be seen light spots on a dark backround surrounding a large inclusion. This is the partially healed fracture looked at in detail in the third shot, The axial alignment of the unhealed damage remnants (small liquid inclusions) can be clearly seen if the pic is zoomed a litle.
The second shot is a detailed closeup of the growth tubes as viewed through the pavilion (back of the stone). No heating damage... likelu that the tubes were formed after the last heating occurred?
The last shot shows clearly the partially healed fracture indicated in the first shot, probably caused by the differential expansion of the Danburite and some differently coloured inclusion as seen. This is a near textbook example of 'fingerprint' healing. However there is a second fracture here also, likely caused by the same inclusion (and in a later heating of the crystal?) running at close to a right angle to the healing plane. This appears to have dislocated slightly the pre-existing fingerprint but itself also then to have healed. The dislocation on the fingerprint suggests strongly that it was caused after the fingerprint had formed (also requiring time on a geological scale) and, having itself healed, it can't result from heating on a gem-cooker's time-scale in recent days.
There is no evidence in this well-included stone of unhealed damage associated with any of the other inclusions, so one concludes that this crystal was not cooked by Man. Or, as I would prefer to put it, 'No sign of treatment'. One has looked (carefully) and found nothing. A negative here is not (IMHO) a proof absolute - so one just states one's negative finding. A good seller will always take back a stone that a customer is unhappy with. IMO, sellers that won't are to be avoided - other than at the level of street-trading - for which a gem customer should either be quite knowledgeable or leave strictly alone :-)
12th Nov 2012 11:08 UTCTopaz
12th Nov 2012 12:00 UTCTopaz
I have bought a Green Topaz for a pretty unexpensive price (about 10 USD), and now I am starting to doubt if that is a natural stone or not. I am attaching a picture of one of the parts of the ring that made me doubt. The stone is well cut but the straight sides that are next to the silver are like shown in the pictures. Is that look of the normal non cut part? Or that is ...glass??
I would appreciate your opinions.
Best regards
Topaz
12th Nov 2012 14:23 UTCOwen Lewis
But all is not lost. As a matter of fact, there is *no* synthetic Topaz in the market as it can't be sold for the cost of making it. However, there is other stuff sold as 'Topaz' and I suspect that this us what you have. What else should you expect of a stone of more that one carat weight and mounted on a silver ring and all for 10 bucks? If I were looking at it I'd start with the proposition that it is most likely glass and try to prove it isn't. To identify correctly what it is, you need to buy the necessary tools and study and practice a bit to learn how to use them effectively - or give the ring to a friendly gemologist to identify the stone for you.
N.B. Real Topaz is quite commonly treated to change it's colour - but that's another story.
12th Nov 2012 15:51 UTCTopaz
Thank you very much.
Yes, this is because it is not allowed to post pictures with more than 1000KB and I had to reduce it. I am trying to post another picture . Let´see if that is better.
12th Nov 2012 15:55 UTCTopaz
The point now is trying to see if you think that this is a Topaz or not...
12th Nov 2012 16:00 UTCTopaz
12th Nov 2012 17:17 UTCOwen Lewis
Experienced mineralogists can sometimes guess correctly a mineral species from just a photo of its crystal form colour, matrix etc. - and their personal store of knowledge. With only very occasional exceptions, it is just a silly game to try do the same the same with cut stones. The best one can do is to reel off a list of species that the stone is *not^. E.g. I'll promise you that your stone is neither Schorl nor Diamond:-D To be sure of what it *is*, you will need to have it tested competently.
That said, I do think it's most probably glass and not worth the postage of sending it to anyone not local to you. Do you have a friendly local jeweller?.
28th Jun 2013 07:38 UTCFria Shay
28th Jun 2013 12:33 UTCBob Harman
So my answer to you FRIA/FIRA is basically what all the others have said. Study and learn. Read the small print about guarantees and return policies before buying. And take all purchases to any local ethical and reputable jewelry stores for an objective, independent appraisal. And even after all of the above, be prepared for being scammed as some of what is sold on tv is overpriced and much is not truly "fine jewelry" CHEERS.........BOB
28th Jun 2013 16:09 UTCStephanie Martin
Have you seen those gold advertisers that will buy your gold jewellery? They take out the stones and throw them in a pile. They sell them in mixed lots to get rid of them. Diamonds too. Tells you that if they were valuable they would make an effort.
regards,
stephanie :-)
28th Jun 2013 17:57 UTCOwen Lewis
-------------------------------------------------------
> It depends on the stone, diamond wouldn't be,
> sapphire and ruby could be.
And so could emerald. Plus, there are look-alike imitations of many others that date back a couple of thousand years or more.The first synthetic diamonds (not gem grade) date to the 1950's. And then there are the treatments of gemstones.....
Re other comments:
- The presence of inclusions is no guarantee of geological origin. You need knowledge and much practice to reliably tell one from the other. A useful rule of thumb is that an experienced gemmologist, properly equipped should be able to differentiate almost all naturals from synthetics - and will veer to a conservative view when in doubt.
- The cost of advanced testing is around USD 100+ a go. This makes such testing uneconomic for stones worth less than XXXX. This makes extensive knowledge and real expertise in the use of standard gemmological tools more rather then less important.
- If an offer looks too good to be true, it probably is.
- Natural, untreated emeralds don't have to cost more than 300/ct - but the good ones do;-)
29th Jun 2013 20:43 UTCTim Jokela Jr
If you want to buy from TV or online shysters and mindlessly accumulate cheap junk that looks pretty, go ahead. But don't worry about whether it's genuine or not. I recommend CZ; it wears well, comes in every color, looks awesome, and is cheap as chips. Life is too short to worry about whether a $10 topaz is real or not. Would you worry about whether a $10 car is real, or $10 heart surgery?
If you love to hunt for bargains, and hate the though of overpaying, or only have five dollars to spend, go shopping at the mall or hit the dollar store.
Gems are not for poor people.
9th Apr 2014 17:34 UTCI1992
Wrap a strand of hair around the stone. Use a lighter to, or try to, burn the hair. If it burns, the gemstone is a fake. If it doesn't burn, the gemstone is genuine.
I was a bit uncertain at first to try this on my carnelian stone, but I done it nevertheless...and the hair didn't burn!! I done it again in front of my friends and they witnessed the same thing.
My mum also tried it on hers with the same result...
Try it!
PS I doubt you would be able to try this after walking into a jewelry store lol. Best bet is to buy a stone from ebay, and the user has set a return policy, so you can send it back to them if it's fake...
9th Apr 2014 17:47 UTCRob Woodside 🌟 Manager
I have a burning question for you:
How on earth could the flammability of a hair depend on the history of a bunch of nearby atoms?
9th Apr 2014 19:36 UTCSpencer Ivan Mather
Spencer.
9th Apr 2014 20:14 UTCRock Currier Expert
9th Apr 2014 20:44 UTCRonald J. Pellar Expert
Ron
16th May 2014 05:39 UTCDashrath International
23rd May 2014 06:02 UTCAnonymous User
23rd May 2014 10:11 UTCRock Currier Expert
23rd May 2014 18:53 UTCAnonymous User
And I hear you on the perceived rarity, I had to go to Namibia for work in the "Forbidden" zone on the South African border. There are diamonds just lying literally lying around there. Don't try to take one though, part of the permit to go in, is you will be extensively, and I mean extensively searched. I bought the engagement stone before my current job gained me valuable contacts outside of DeBeers control. I just don't have the bankroll, desire, or the stupidity to risk my well being to buy/sell other than if I was in the market myself.
Thanks again,
Mike
24th May 2014 17:55 UTCOwen Lewis
You done good. Stay away from the treated diamond trade unless to you have a *very* good understanding of what you are about. My personal advice also is not to purchase new in the retail trade. Reputable and expert auction houses, such as Bonhams, have regular sales of jewellery at their sites around the world and (less frequently) of loose gems also. These auctions (if you set up with the auctioneer in advance) are accessible in real time with bidding on line. There are, occasionally, excellent bargains to be had. this is *not* like E-bay. Register with the auctioneer well in advance; view the catalogue(s) up to 14 days before the auction - and ask for an 'auctioneer's (expert) report before deciding to bid. These houses occasionally sell minerals and fossils too. But you will not be in the ten-buck market.
Don't over-fret over Rock's comment about diamonds chipping (yes, they are relatively brittle bit nowhere as near so as (say) spodumene. At 72, I have my great-grandmother's diamond ring; yes, the ring and mounting are a little worn (it has been in *reasonably careful* daily use for about 100 years) but the three stones are as good as when they were cut - 'Old European' cut. This sold at auction for appreciably less than half the retail selling price as item of 'estate jewellery' - and less than one fifth the cost of the same carat weight and grading of stones bought new from the likes of Blue Nile, that undercuts the 'shop-front' retail market.
1st Jun 2014 18:34 UTCcascaillou
In the first place you need extensive knowledge of gemology. But there's no straight answer to that question. It all depends on the nature of the stone, and also what are the different existing methods of synthesis for this specific mineral. Observation of internal features under the microscope is usually a good start, but further testing is often required, and while some synthetics are easily spotted, for some other stones the only way to go is through laboratory analysis methods.
Let's add that synthetics aren't the only concern, you should also be careful about treatments and imitations.
I remember when my grandma brought me a ring with a dark sapphire inherited from her sister, and asked me about it, well that was such a perfect textbook case... http://www.ruby-sapphire.com/images/verneuil-synthetic-corundum/figure04.jpg
Since that day, I'm very reluctant to take a look at wedding rings from close relatives...sometimes a candid illusion is worth all the truth in the world.
28th Jun 2014 22:42 UTCMe
That said, I just found a ring at the beach (yes i asked around no one claimed it) and it has some purple stones in it. I don't know how to tell whether they are real or not. How can I tell and how can I get them out of the ring without any special tools. Please help me.
29th Jun 2014 00:40 UTCRock Currier Expert
28th Aug 2014 15:15 UTCshane brady
28th Aug 2014 20:48 UTCOwen Melfyn Lewis
Go back to the books.
Not all ruby is magnetic and synthetic sapphire certainly is.
Iron plays no part in the essential formulation of ruby but may, coincidentally be present is minute trace amounts. The chromophore is Cr in substituioin for Al in a quantity between 1-4% by mass.
For sapphire (blue), no Cr is required but the presence of both Fe and Ti in combination. The colour is cause by a valency charge transfer effect. I.e. No iron == no (blue) sapphire.
Sorry, but your advice is misleading to the many who seek an easy 'one club' solution to complex matters. The correct approach is:
1. Is the mineral species corundum? Y/N
2. If Y then:
a, If red and of gem quality, = ruby
b. Or if blue etc., then sapphire.
c. If colourless etc, then white sapphire.
d. If yellow, green, purple then yellow (etc.) sapphire. Colour is used as an adjectival (descriptive) modifier.
3. If N, then start again to identify some other mineral.
And, of course, to a mineralogist, it is *all* just corundum :-)
28th Aug 2014 21:57 UTCAlfredo Petrov Manager
29th Aug 2014 01:13 UTCOwen Melfyn Lewis
Corundum is synthesised by one of several methods. The synthetic is diffentiated from the natural by microscopic differentiation in the crystallisation. Here are two examples:
1. This is a sapphire produced by the flame fusion process. The curved growth lines in this specimen are absolutely clear and are diagnostic for corundum synthesised by this method.
2. Here is a photomicrograph of of pink sapphire produced by the flux melt process (Chatham method). What is seen is a fragment of the chromophore Cr2O3 bound up with the flux and not fully dissolved in the Al2O3 before the cooling of the melt prevented completion of the process. The 'lace' formed in this way can be mistaken, if unpracticed, for a partially healed fracture in natural corundum but, with some experience, this characteristic is diagnostic of the flux melt process.
To make the point plain, here is another example of this 'lace', this time in a flux melt emerald (Chatham method)
N.B. Synthetic emerald is also usually weak to moderately magnetic ;-)
29th Aug 2014 02:03 UTCAlfredo Petrov Manager
The majority of solids are noticeably attracted to strong magnets, even things with no iron in them at all, with the exception of a minority of diamagnetic ones that are repelled (graphite, bismuth, etc). And as time goes by, stronger and stronger magnets are available to the general public and so these effects become more easily noticeable, and the pool of materials that we can say are "not attracted to a magnet" has shrunk a lot!
Nevertheless, if you compare a typical natural sapphire crystal and a synthetic, you would expect to find that the natural one is more often strongly attracted to a magnet just because of its highly magnetic inclusions, and that synthetics were more weakly attracted, quite apart from the minuscule amount of chromophore iron in the sapphire structure itself. Natural material from different localities/geological environments would of course be expected to be variable in properties, including magnetism (and that might sometimes help pin down where a gem comes from).
Anyway, as to whether such magnetic effects are "noticeable" or not, much will depend on the strength of magnet used, sample size, and several other variables, with no quantitative data being determinable, so the experiment is more of a didactic curiosity than a useful identification procedure, because we can't directly compare and standardize our observations :(
29th Aug 2014 07:06 UTCReinhardt van Vuuren
When you buy gems (set in Jewelry) from a retail outlet the sales consultant has to use certain terms for certain gems (here in South Africa at least)
if it is Synthetic the sales person will simply call it Synthetic Sapphire.
if it is Natural from the ground BUT its been treated (heat, irradiation ext) the sales person has to call it Genuine Sapphire.
if it is Natural from the ground and is not treated in any way accept the cutting done to it obviously the sales person may call it Natural Sapphire.
now in light of the above there are some gems where a certain level of enhancement is considered "Normal" for example Heat Treated Tanzanites or oiled Emeralds but these still need to be sold as Genuine not Natural.
As I say I'm not sure if this applies everywhere in the world but this is how it is here in SA.
Also something interesting to mention is here in SA we don't use the term WATERPROOF it has to have a ATM or BAR reading. :)
29th Aug 2014 13:09 UTCOwen Melfyn Lewis
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> No, Owen, I think you missed the point that I was
> responding specifically to Shane, who claimed
> magnetism could separate natural from synthetic
> corundum....
But so was I so responding. This technique is, for the stated purpose, a busted flush. It is so far from being diagnostic as to be of dubious value even as a supportive test. I would never bother to use it on corundum, other than to satisfy some curiosity.
It is possible to build a (fairly expensive) rig that, together with a little use of maths, allows magnetic observations by the amateur to move from the purely qualitative to the quantitative - but one then runs into the brick wall of the uncertainty of exact chemical composition in a fistful of samples of the same mineral. Like the use of Mohs's Scale, one can spoil its certain utility by attempting to over-refine its application.
29th Aug 2014 14:45 UTCOwen Melfyn Lewis
-------------------------------------------------------
> So much been said on top I just wanted to add
> something lets hope it hasn't been mentioned:
> When you buy gems (set in Jewelry) from a retail
> outlet the sales consultant has to use certain
> terms for certain gems (here in South Africa at
> least)
> if it is Synthetic the sales person will simply
> call it Synthetic Sapphire.
> if it is Natural from the ground BUT its been
> treated (heat, irradiation ext) the sales person
> has to call it Genuine Sapphire.
> if it is Natural from the ground and is not
> treated in any way accept the cutting done to it
> obviously the sales person may call it Natural
> Sapphire.
> now in light of the above there are some gems
> where a certain level of enhancement is considered
> "Normal" for example Heat Treated Tanzanites or
> oiled Emeralds but these still need to be sold as
> Genuine not Natural.
> As I say I'm not sure if this applies everywhere
> in the world but this is how it is here in SA.
Hi Reiner,
You touch on big subject, albeit one more for gemmologists or jewellers than for mineralogists :-) The aim is to keep trading honest and to serve the public good. That's fine but, IMHO, is an end not well served by the twisting of the meaning of words to suit some end, however praiseworthy that end may be.
The bare fact is that synthetic (lab-made) gemstones are, in every way, the real and genuine article, be they diamond, ruby, sapphire, emerald, etc. In fact, the 'etc.' is not so big as there is no economic case for the synthesisation of the lesser gems. Topaz *can* be synthesised but has never been so on a commercial scale as the economics would make no sense - no market for it at the probable volume/price level..
Tanzanite is a valuable gem but has not (yet) been synthesised. Rather synthetic forsterite is doped to look rather like tanzanite and is sometimes passed off as tanzanite. In this case, although the substance is of synthetic production, its correct trade description would be either 'imitant' or 'simulant' and not synthetic. Synthesised colour change corundum is similarly sold as an imitant/simulant of alexandrite (cc chrysoberyl).
Then there are reak cgems that, to all intents and purposes, are only known from synthetic production. E.g. the cubic phase of zirconium dioxide (CZ), yttrium aluminium garnet (YAG), gallium gadolinium garnet (GGG). All make beautiful gems in their own right. And should not have to be labelled as diamond simulants.
Quartz is the only cheap gemstone widely synthesised for sale for jewellery. This is because the commercial synthesisation of quartz as gemstones rides on the back of the enormous scale of quartz synthesised for industrial purposes.
The treatment of geologically formed (or, nowadays, synthetic) gemstones to enhance their attractiveness, is as ancient as the use of coloured stones for adornment or ornamentation (2,000 years++). Roman emperors complained about such practices and even ordered the destruction of all books containing 'how to' recipies. Like the book-burners of all ages, they failed to eradicate the thoughts of other men. The vast majority of gemstones receive some enhancing treatment or other. Many treatments are detectable with a high level of assurance. Some other and very common treatments are, in truth, undetectable.
What is a treatment? A true story. A friend was given a pair of 'natural' hyacinth zircon earrings by her husband. The stones were a matched pair. She put them away on a jewel case where they sat in a drawer for about six months before she next took them out to wear - and they were no longer a a matched pair - one was orange and one was brown! What might have happened? Had her husband been swindled?? I suggested that she leave them both sit on a sunny windowsill for a week, after which, if there was still a problem, she should revert for further advice.
At the end of the week their colour was once again matched. Now what I advised was a treatment of her stones; though both were 'natural' one or both were not colour stable without fairly continual low level energy input (as provided by sunlight). Declare such treatment? Pish! It's absolutely undetectable (as are the large majority of the widely used irradiation treatments). My friend has a pair of earrings of sentimental value to her and that value of which is now further enhanced by the knowledge that they have lives of their own that require her attendance if they are to appear as she would wish them to look.
This is not to suggest that *all* treatments are so innocuous - or undetectable. That's not so. This point is that to lump together all treatments in one simple trade description and declaration is simply ignorant and unhelpful to the buying public.
As a chemistry tutor once said to me over half a century ago, "All things are simple to the simple-minded, Lewis".
29th Aug 2014 15:17 UTCReiner Mielke Expert
29th Aug 2014 16:50 UTCDoug Daniels
1st Sep 2014 19:15 UTCOwen Melfyn Lewis
-------------------------------------------------------
> Just to play the devil's advocate. In my opinion
> once you cut a stone any stone ( natural or
> synthetic), it just becomes a pretty bauble. If
> not for irrational valuation (example cut diamond
> vs. cubic zirconia) the concern about synthetic
> vs.natural would be irrelevant. Now if people
> mounted uncut stones I could understand the
> concern.
Reiner, most stones are pretty ugly even if anyone bothers to cut them :-) As a broad definition, those stones that are enhanced by polishing and, maybe, faceting as well are *gem* stones :)-D
Mais chaq'un a son gout...
8th Oct 2014 12:09 UTCBollywoodtrinkets
But here are a few tips to help you get started:
1) Synthesized gems or synthetics of certain types react positively to a magnetic test, bring a strong rare earth magnet near them and see if they get attracted ... this is due to residual trace metal elements in the gem left over from the industrial manufacturing process. Natural gemstones and diamonds will never test positive to a magnetic test.
2) A simple refraction test will reveal most fakes and simulants, all gemstones have a known refractive index and synthetics tend to show clean values across the gem an are easily detected as opposed to natural gems which contain higher variations.
2) In the case of emeralds you must first realize that they actually belong to the Beryl family of gemstones and are actually one of the few precious stones that come from the family of semi precious stones. An emerald is nothing more than pure Beryl coloured green by the element Chromium, and it may further interest you to know that Rubies and Sapphires belong to the same family as Beryl, ruby being coloured red due to metal oxides and sapphires blue again due to secondary elements or impurities contained in the Beryl. Gems that are themselves colourless but exhibit colour due to trace elements or impurities that are not part of their chemical composition are known as allochromatic or 'coloured by others', and Emeralds, Rubies and Sapphires are prime examples of allochromatic gems.
Unfortunately Beryl is one of those gemstones that is highly susceptible to false colouring, irradiation, oiling and many other techniques for use as simulants in the industry and i would not personally recommend that any customer purchase an emerald, ruby, star ruby or sapphire without a certificate or authenticity or guarantee from the jeweller where the source of the precious stone is clearly identified and accompanied by purchase records you can see for yourself. A good quality emerald, ruby or sapphire should actually cost more than a diamond of equal carat ... and if you expect to see certificates for diamonds when buying them, you can ask for one when buying an emerald (although you may have to end up paying for the test yourself, since most jewellers mostly only buy from their own known sources and randomly batch test rather than test each stone).
8th Oct 2014 17:23 UTCMark Heintzelman 🌟 Expert
The major flaw I see here is that Sapphires and Rubies do not belong to the Beryl group, they are Corundum and members of the Hematite group,. An entirely different species with entirely different properties. What good is offering your customers advice if your "facts" are simply incorrect even down to the fundamental level of description?
11th Oct 2014 18:12 UTCOwen Melfyn Lewis
13th Oct 2014 03:10 UTCRock Currier Expert
3rd Nov 2014 12:06 UTCOwen Melfyn Lewis
It may be a coloured transparent crystal or it may be the same in glass. If a crystal, its species and variety need to be determined by testing - and that requires some knowledge and equipment. Differentiating a synthetic (lab-grown crystal) from one geologically formed requires more experience - and can has a great effect on the value. Also if the crystal has been geologically formed, has it been treated to improve its appearance and value?
I would take it to your local jeweller and ask for an opinion as a start point at least.
To play a guessing game, I would say that it might be an iolite (old gem name for coloured cordierite). This is from the lowish refractive index and hint of pleochroic colours that I think I detect in the pics. Cordierite is not synthesised commercially so, if iolite, then it was formed geologically. Also iolite is not treated commercially to enhance it. Again *if* iolite, I'd put the weight in the 12-18 ct range. Iolite is not especially rare but is not often seen in jewellery as other gems are preferred. However, an iolite of that size and with no major flaws would have a retail value upwards of around USD700. So treat it with care until you have it properly checked out.
Good luck!
4th Nov 2014 05:58 UTCRock Currier Expert
4th Nov 2014 10:53 UTCReinhardt van Vuuren
4th Nov 2014 14:51 UTCOwen Melfyn Lewis
But to continue the fun...
Refraction and reflection:
- When a beam of light travelling in one medium(air) reached a flat boundary with (say) a faceted gemstone, one of two things happen.to the light. Some it is reflected off the surface, bouncing back into the air and some enters the stone where it is either absorbed, passes through or is reflected back of the rear of the stone. For any angle at which the light strikes the air/gem boundary whether the light is passed through or reflected is a differentiating property of the species looked at. It is not a unique property but is the same for only a few species of gem mineral. This property can be measured accurately and have a numeric value, called its refractive index. Lists of refractive indices are published to assist in the identification of gemstones and all other minerals.
- But what if one can't measure the RI? With a little experience, one comes to know that a very 'glittery' faceted surface indicates a high RI (say the RI of corundum through to diamond) - or some specific treatments, Also, look at light coming from the back facets (pavilion) of the stone. In the third shot, from prior experience it can be concluded that light is seen to be coming through the stone from the material behind it (a condition called 'windowing'. For this to happen needs the angles pavilion is cut at be too shallow to math the RI property of the stone (its a cutting defect that saves money as the stone is smaller, using up less of the gem material for a given face size. Guessing that the pavilion (backside) is cut to a normal shape this indicates an RI no higher than that for beryl and even down to that for fluorite. Common glass would also fit this bill as glass can be doped to make its RI anywhere between high and low.
From the colour and the assessment of a modest RI, quartz - amethystine quartz - or glass - would probably be everyone's first guess I suggest. But look at the third shot; a light blue predominates over traces only of purple. Amethyst does not do that - cannot do that. But some iolite does. If one enlarges the pics, flecks of that light blue can be found in the other shots too. There is a colour change effect that occurs in many coloured and transparent minerals according to the angles from which they are lit and viewed. This effect is often quite weak and needs some simple equipment to make it apparent. However there is a small number of minerals in which the effect (called pleochroism) is sufficiently strong to be visible without assistance (except maybe from a little magnification).
Pleochroism is strong in iolite. In pure form, iolite (cordierite) is colourless. The main cause of colour is the inclusion of some Fe in the crystal as an impurity. Nature running a dirty workshop, there are often small traces of other elements so that the pleochroic colours can vary from sample to sample. Typically, amethyst shows two pleochroic colors only, purple and reddish-purple. Iolite usually shows three colours with some alternates as follows: violet, colourless/yellow, light blue or green.
Both quartz and cordierite being anisotropic, each have two different RI's (just to complicate matters) and these are largely spread over the same narrow range - so both fit with the observation of moderate/low RI.
So iolite. Am I sure? Of course not; it needs testing. But my guess results from logical process and is not blind.
7th Nov 2014 06:14 UTCReinhardt van Vuuren
7th Nov 2014 11:09 UTCOwen Melfyn Lewis
Giving an opinion formed from the colour and habit of a crystal on a known matrix with *reliable* locality information is one thing (for expert mineralogists/geologists). To give an opinion on a cut and polished material just from a photograph is quite another; almost always, it is wiser to say nothing :-) And where one says something, it's main purpose should be to stimulate the owner into getting it properly tested.
24th Nov 2014 18:39 UTCNorman James
( My first warning sign ) Supplier offers 7 day return for full refund less 10% handling . Also offers to obtain a certificate at a cost of R300 ( $30 ). Is it possible to send me some photos of inclusions for Tanzanite as well as Topaz and Acquamarine . As I do not own any Stones yet I have no idea what they look like or what to look for . I look forward to your reply .. Regards Norman
Look forward to your reply .
24th Nov 2014 22:12 UTCOwen Melfyn Lewis
So you are just starting out? What do you want to do? Just buy gems because they're pretty, impress the ladies and are more permanent possessions that cases of beer :-) Or do you want to learn how they are made, which of them can be modified by treatments and how. Which are synthesised on a commercial scale, what their fair value is and much more besides? If the latter, you need a couple of books and some basic instruments to make a start with. And a small packet of reasonably cheap gems that have been examined by someone who knows butter from margarine, so that you can start to practice with no mistakes in the identity of what you are looking at. Throw a lot of hours at it and a basic competence can come in 9 months - though it takes many three years to do it. There are formal courses, examinations and qualifications if that route attracts you, up to and including a PhD. So the skies the limit....
Before making a good start, asking for images of inclusions in gems is jumping in at the deep end before learning to swim and with lead weights ties to your ankles :-) Start by learning the different crystal systems, their more common forms and the sorts of things you might expect to identify in gemstones for yourself - once you have some fairly expensive optical equipment. But of course you need none of these things to impress the ladies with sparkly bits of colour.
Use the search box at the top of this page. Type in 'inclusions' and you will pull up more threads with pics of inclusions that you are likely to want to read. If you are really interested in this stuff, what can you tell me about my avatar pic? Anything at all that crosses your mind and is related to crystals and the properties of light. If you come back with something, I'll PM you some more pics that explain some of the features. Actual size is about 1mm long. Here's a closeup.
Trying to ID tanzanite by its inclusions is a bad idea. To ID that gemstone once cut and facetted, you need to be able to:
- Determine its SG to 2 DP.
- Measure its two refractive indices to 2DP - and interpolate the third decimal place.
- Observe its different colours and determine how many there are.
If you can do those things, you will know for sure you have a tanzanite, whether or not it has been heat treated - or whether you have a faceted piece of blue glass, synthetic forsterite (the usual simulant other than glass) or some other zoisite that is not the valuable tanzanite.
29th Jan 2015 07:05 UTCH. Claire Scheepers
29th Jan 2015 13:28 UTCOwen Melfyn Lewis
However, it is quite likely that any of these three stones has been modified by man, tanzanite and aquamarine by heating and topaz by irradiation. The commonality of heat treatment of tanzanite pieces is > 90%, this modifies the colour to suit market pre-conceptions and expectation and is routinely done by the mining company before grading of the rough.
Colourless/light brown topaz is very probably untreated but market demand is weak. Pinks and blues should always be suspect. There is no certain test for the colour changing process; opinion should be based only on the quality of the trail attached to the material from the moment it was mined. The 'London' and 'Swiss' blues are always the product of treatment - but are also fairly cheap stones. The danger area comes with fine pink specimens which have recently become expensive and sought after. Fine pink topaz can be be found (but very rarely) in nature and it is also known to result from the irradiation of some topaz (Brazilian especially). In almost all cases, the only recommendable course is to pay for a specimen only what one would pay were it known to be treated..
The natural colour of almost all aquamarine is a sea-green. Historical research by John Sinkansas, the noted American mineralogist, gemmologist and compiler of the great work, 'Emerald and Other Beryl', concluded that blue aquamarine was virtually unknown until the 20th century and observed that (by the 1980's), nothing but blue aquamarine was to be found in the gem market. I count myself lucky to own a 15ct cushion cut sea-green aquamarine.
20th May 2015 23:43 UTC1gengehm
I am new to this message board but I have been a rabid gemstone enthusiast for better than 30 years and I have a question, this has bothered me for better than 7 years, you may say to yourself why not just bring their the gem into a gemologist office to have it identified as to whether it is genuine or manmade, the thought for me is one of finances, to me and to most I would think that every dollar counts when it comes to investing into fine gems,... Wherever it is you may find the gem .. Most individuals are not out there in the field it didn't their hands in the dirt looking through thousands of pieces of what looks like... Mostly because of lack of time to be able to do this or even again the old adage every dollar counts, the question I have is this and I will explain exactly what this gem looks like,and of course I will post photos as soon as I am able... What I have is ..
a color change garnet that is cushion in shape its weight is approximately 5. 20 carats..when I found the gem it came from a based in Tucson Arizona back in 2001, in the sunlight this gemstone has a most wonderful medium dark sky blue colour clean and clear with an exceptionally fine luster,.. When I bring the stone into incandescent light the color of the gym changes to a pinkish orange e red with the same brilliantcolor and clarity.., as if I were to be seen the stone in direct sunlight or for that matter anywhere where the Sun may be glowing whether it is overcast cloudy blue sky or any other type of weather or shade of sunlight you view this gemstone in the color is a wonderful blue.. The 2nd colour change that I mentioned earlier which is the orange e pinkish red viewed in incandescent light, such as an old-time flashlight, or a lit match or a lite BIC or as well and incandescent light bulb of any strength the stone has this wonderful Orangi pinkish red hue that I'm speaking of.. The other change that is noticeable is that in combined light of incandescent light and sunlight this gemstone has a tendency to go purple, and the last color change is when viewing this gemstone under a full wave fluorescent light weather this late is handheld or a black light or something of that nature long wave fluorescent I should say.. The gem stone at this has a further color change which is a very brilliant kind of copper green color with some tan beige and brown into it.. To explain further when I hold or touch the gemstone with my fingers or hand,.. The stone feels cold and heavy..this for all intensive purposes looks feels and acts like the real thing which would be a..bekily Madagascar origin color change garnet.. I have seen many one or two hundred color change garnets in the time that I have been first looking at gemstones.. I have seen this type of color change garnet and one in 2 carat size is Cell for as much as $8000USD,,.. This goes to the fact that some one may have purchased this Gem through many of the cable gemstone companies that sell gemstones lose for a value,...I have a small bevy of gemstone people that I have worked with for better than 30 years....but this particular color change garnet gemstone confounds me because I am not really sure if it's the genuine article so I have not yet shown it to the public in general.. But after studying this for better than three years, by reading and watching and understanding everything I can about color change Stones, I am convinced that this gemstone is the genuine article... So ultimately I also wonder what is the gemstone actually worth to one who really enjoy owning a gemstone as thimy collection of gemstones is extensive I have been collecting since 1983 and of course always looking for the best possible value when I obtain these gemstones,,.. And as I provide them to others I have always been extremely fair about the value..,,, I have been providing these gemstones online for better than 12 years,,.. I was available to people on overstock.com up until the day in which they ended their general auction site..., and had provided better than 465 separate gemstones to just as many collectors.. with all of that only seven individuals who I provided a gemstone to asked that their value be returned..most or better than 95% of all my clients were very pleased with what they obtained..,, and its I guess the fact that I am very much involved with them until they are happy with the gemstone that they obtained..,, I have always giving everyone a chance to return a gemstone for up to 10 days after obtaining that gemstone so if they chose to have the value returned to them I did so without question.. Anyway I understand the quandary of having some gem stone and not necessarily being able to figure out whether you have the genuine article or a man made item..,,if what you read in this message about the stone that I have explained.., I would really enjoy getting some feedback,,.. Only because I have been struggling with what the value of this gemstone maybe to a nother collector..,, in retrospect as I do obtain a gemstone I usually keep it and study the stone for at least 2 years, to be able to understand all aspects of the gem because of its one-of-a-kind presence and and how the gemstone reacts to all possible environments, in the aspect of wearing the gemstone in a fine item of jewelry..,, and as well so that I may explain to the collector exactly what it is that they're consideringto obtain..,, most of my experience with online or television type gemstone dealers is that they go through so many separate gemstones that they do not necessarily take the time,,, or put in the effort to understanding the stone if its value is extraordinary outside with the fact that they might spend as much as 30 minutes trying to convince someone that they should have came the same stone that they are explaining to you..,, and then they move on to another, this to me is not the best way either to purchase a gemstone that for all intensive purposes once you obtain it you would like towhere and share this gemstone for many many many years or decades forward, that's why one particular collector to another may spend a X amount of dollars for that particular gemstone,for me I tend to remember each stone I've ever sold and as well I keep a record of it in photographs, as well for me it is very difficult to put a value on a particular gemstone knowingin understanding what the collector would want..,, so anyway I look forward to your feedback thanks for reading this.. And I will be posting photos of this gem stone in my next few messages.... Gratis
21st May 2015 00:20 UTCOwen Melfyn Lewis
21st May 2015 00:22 UTCBob Harman
21st May 2015 15:56 UTCRob Woodside 🌟 Manager
21st May 2015 20:54 UTCAdam Kelly
If you have a 5ct cushion cut without an apprasial, i hope you didn't pay much.
If it IS real, it is well worth getting appraised.
Good luck
21st May 2015 22:51 UTCOwen Melfyn Lewis
But 'garnet' is really too vague. I'd like to wait until we hear what tests have been performed and with what results before moving to discuss his question, as to synthetic origin or not.
@ Rob: I have a CC fluorite too. Now that one does do blue and pink :)-D
5th Jun 2015 18:24 UTCRock Currier Expert
15th Jan 2016 14:05 UTCSteve Thomay
I am contacting u about my 5 ct. TAnzinite ring. I bought it from a cruise line. It's beautiful. Purple blue w/ fire.
I had my ring reset. They called me & said it has a fracture in it now. When I gave the stone to them it was perfect.
The jeweler said they do t know how it be fracture got there
The jeweler sent it overnight to GIA to see if stone was ever filled?
I have only had ring less than. A year.
Again, would I have seen the filled fracture filling with. Naked eye?
Do think the jeweler hAd fractured it when he was resetting the tAnzinite ring .?
Thank u for your reply
15th Jan 2016 18:29 UTCRob Woodside 🌟 Manager
15th Jan 2016 20:43 UTCOwen Melfyn Lewis
I'm afraid that you can't get a satisfactory answer to your query based on the information in your posting but here are a few general pointers that may help:
- Tanzanite (good examples are lovely gemstones!) does not show 'fire' but different facets can show three different colours, depending in the direction from which the stone is viewed and if the stone has not been heat treated. These colours are most usually a burgundy red, royal blue and either yellow or a light greenish-blue. All but the very best (over 95%) are heat treated to destroy this effect before the stones ever go to a cutter (or are sold off as mineral specimens). Heat-treated gem quality tanzanite will only show the colour blue or - as you say - a purplish-blue.
- Fire is a term used to describe the splitting of white light into the colours of the spectrum when the light has been strongly refracted as it enters a gemstone and is bounced around inside the stone by multiple reflections before exiting the stone in the direction of a viewer. The longer the light path inside the stone the greater the refractive dispersion becomes and the more likely it is to see the various spectrum colours (seven of them), usually just one colour in some of the small crown facets that surround the table (main face).
- Tanzanite is commonly fractured before it is brought to the surface of the mine or sometimes during the heating process. A good cutter will cut the stone so as not to include any of these fractures - but sometimes stones reach the market that do have small fractures remaining in them. These fractures may or may not be filled. Where they are unfilled, a layer of air - sometimes only about as thick as the wavelength of light itself is present in the fracture. Such a thin film of air often causes a reflection of light from both the front and the back surface of the fracture and these two reflections can interfere with each other causing an irridescent colour display that usually looks like a series of brightly coloured bands. To the non-specialist, this thin film colour effect can look rather like 'fire' but is not. Look carefully and you can see the colours produced are not the pure spectral colours produced by 'fire'.
Below is an example of thin film colour effect caused in a piece of colourless gem rough (labradorite).
.
There is simply nothing to say about whether the stone was fractured when you bought it, after you bought it or after it passed into the jeweller's hands *except* that if the 'fire' you thought you could see coming from the stone was one of the reasons why you bought it, then it is probable that the stone was already fractured when you bought it.
Here's another example of thin film interference coming from a fracture in a tourmaline. I arranged the lighting here so that the stone can't be seen at all, only the colours caused by the presence of a small fracture. Pic taken under the microscope at about x40 magnification.
To finish, here is an example of how fire can appear in round diamonds. These are Old European cut which show more fire than is produced by modern cut diamonds (after c. 1920) as the modern fashion is to reduce the fire shown by the cutting and to increase the brilliance (white light rather than coloured light returned from inside the stone to a viewer).
Your chances of getting your money back are effectively zero, especially so long after you bought the piece. Sorry not to have better news for you.
18th Feb 2016 12:37 UTCH. Claire Scheepers
Further comments - it is unlikely that Tanzanite would produce 'fire' as it does not refract light in a way conducive to this phenomenon. -- As stated previously - if you already saw 'fire' in this stone then the fracture may have already been present - which would be very poor form from the person who sold it to you.
Usually though a lot of 'fire' can indicate cubic zirconia coloured to look like Tanzanite.
I have twice in my career been contacted by jewellers who have managed to fracture Tanzanite by using ultrasound to clean jewellery, so you could also try asking how it was cleaned, - if he / she is not aware that ultrasound is a very bad way to clean Tanzanite and admits to the ultrasound you may actually have recourse.
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Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 16, 2024 11:26:39