Is it true that green amethyst fades?

[Jambalaya]

Hi, I know that green amethyst is prasiolite. I'm not talking about rare natural prasiolite, but about purple amethyst that was heated to produce the light green stone commonly known as green amethyst.

I adore this stone. I love the beautiful seafoam green, which reminds me of the ocean, and I also think it's an incredibly tasteful shade. I have numerous pieces of green amethyst set in silver which were all very inexpensive, and one pair of green amethyst pear drop earrings set in 18kt gold from an expensive jeweler, Kiki McDonough. Last night I bought a really stunning large green amethyst ring set in silver. It was incredibly inexpensive - so cheap that I won't mention the price because I fear you'll think badly of it when I show it in SMTB! But it's a large, green, sparkly stone, and I adore it.

So imagine my consternation when I go to read a little more about green amethyst and I see that it fades in sunlight! I have researched green amethyst before and never come across this. Kiki McDonough sells green amethyst pieces for around 1000-7000 American bucks (although my Kiki green amethyst earrings were nothing like that price) and if green amethyst faded, surely she'd be plagued by angry customers saying how their stones had changed color?

Does this fading happen only if someone wears the stone regularly in direct sunlight on a ninety-degree day? Or does it happen with weak sunlight all year round? I live somewhere with long, cold, snowy winters, and while it can get very hot briefly in the summer, I don't really wear my jewelry on a very hot day as I just don't want my nice stuff getting all sweaty. I don't wear my jewelry to the beach or pool, and I don't take it on vacation.

Would wearing it around town on a sunny day at around 80 degrees fade it? I'm just confused over how much heat and sun is needed to cause this fading, and if you really have to expose it relentlessly for the fading to happen, or if casual summer wear can do it? Is fading a real threat, or is it something that "can" happen but in fact rarely does, unless you expose it heavily to the sun over a long period of time?

Thanks xxx

 

[Jambalaya]

P.S. In reading about this topic, I also read that morganite, kunzite, aquamarine, smoky quartz, and all kinds of irradiated stones can fade! Huh? I've always read that blue topaz (irradiated of course) is stable, and I've certainly never heard of aquamarine fading. I read quite a bit about aqua when I bought mine, and I never read about fading. I believe my aqua to be unheated due to its blue-green color, but I also have a heated aqua pendant. I read around the subject and I never heard any suggestion that the treatments of aqua aren't stable, and also I never heard that smoky quartz and blue topaz weren't stable, either. The impression I had about aqua, blue topaz and smoky quartz is that the treatments accepted by the trade - heat and/or irradiation - were very stable.

I don't know anything about morganite and kyanite, but it they are particularly prone to fading, I won't buy any.

I thought that the traditional treatments of the stones above were seen as stable, and now I'm confused.

 

[Jambalaya]

Just found this article from JCK online about a color fade test, and this paragraph is interesting:

"Some materials don’t fade significantly for one to several weeks in the fade test described above, and will last a few to many years under normal wear or display circumstances. They include pink kunzite, some rose quartz, some pink to red irradiated tourmaline, some apricot morganite and all deep blue to deep green maxixe beryl (may have been irradiated). On rare occasions, some amethyst has been reported to fade very slowly."

Here is the article: http://www.jckonline.com/article/283706-Fade_Testing_Has_The_Time_Come_.php

So it looks as if the nuances of gemstone color-fade have been lost and therefore all the stuff on the internet about green amethyst fading is not really a concern, and also that pink kunzite is good to go.


Have I got that right? Or is the color of green amethyst less stable than purple amethyst? Could do with some advice from the experts! And what about morganite?

 

[mastercutgems]

Hello Jambalaya;

Correct me if I am wrong as I have been once or twice

The vermarine or prasiolite or any other name it may go by; green amethyst used to be from the Montezuma district of the gem rich Minas Gerais , Brazil. It was a form of lighter amethyst (natural) that they found would heat not to orange or golden yellow but a mint to medium green. I have heated the material myself many years ago when it was available but not any longer. It was stable then as we used to set them in a window facing south for weeks along with gem minerals like kunzite, morganite, etc. to see if they would be stable. Some were and some were not.

I find in my search for the treated things like those now are either a hydrothermal or irradiated material and I do know the hydrothermal is stable and the nuked stuff usually is not in the pastel colors.

Normal wear usually did not fade non-irradiated material or synthetics; but on heavily treated gem I always looked at them like I would costume jewelry; and not put a lot of money into them and did not put a lot of money into the settings as well; just buy them and enjoy them and wear the heck out of them and if you do not pay a lot; you do not lose a lot when they fade, chip and/or just go out of style.

Just my experience with the mineral.

Most respectfully;

Dana Reynolds
ASG Certified
Supreme Master gem Cutter
#96CGE42

 

[LD]

Kunzite and Morganite are notorious for fading. I've seen a Kunzite fade even without direct contact to sunlight - it faded in my safe!

Smokey quartz I've never heard of fading - neither Topaz.

As for green amethyst - I think it's one of the gems that may fade but I think it's probably different for the natural material (probably won't fade) compared to the irradiated material (which may fade).

 

[Jambalaya]

Thanks for the replies.

My green amethyst items are all low-quality purple amethyst that was heated to a pale green. They're not irradiated or anything else. So they don't fade like kunzite and morganite? I'm confused though because the quote from JCK above says pink kunzite doesn't fade. Weird about your stone in the safe, LD. Also, Kiki McDonough charges approx $5,500 for a pair of morganite earrings. If they were so prone to fade, wouldn't she have a bunch of very angry customers? Doesn't this fade only happen if exposed for a long time to extreme sun? I'm just wondering if this is one of those things where "can" and "occasionally" and "under the right circumstances" has morphed into "this stone fades." Because Kiki isn't the only expensive designer selling semi-precious stones for thousands and thousands of dollars which apparently fade - there are many other such designers specializing in semi-precious like Ippolita, Elizabeth Locke, and Jude Frances. Kiki sells pear green amethyst drops at Neiman's in California - definitely a sunny place. If these gems are so prone to fade, I don't understand how they are used in jewelry and priced in the thousands.

 

[MollyMalone]

I'm not talking about rare natural prasiolite, but about purple amethyst that was heated to produce the light green stone commonly known as green amethyst.
If the current landscape is similar to what it was in June 2005 -- when this Modern Jeweler article, Green Amethyst: Hail to Pale, appeared -- it's likely that your "green amethyst" is plain ol', colorless quartz that's been both gamma-radiated & heated:
http://www.modernjeweler.com/web/online/Colored-Gemstone-Gem-Profiles/Green-Amethyst--Hail-to-Pale/1$455

The JCK article you found dates back to 1996, but I've not been able to quickly put my hands on (via Google) anything recent that offers definitive, sound conclusions (e.g., based on a GIA study) re fading of these particular green stones, sorry.

 

[Jambalaya]

OK, so if my stones are gamma-radiated and heated colorless quartz, does this mean that they are they not prone to fading? Is it the prasiolite (which is created from heating low-quality purple amethyst until it turns pale green) the one that's prone to fading?

I couldn't be more confused at this point.

 

[minousbijoux]

Unfortunately, there is no one size fits all answer to your question. Depending upon the treatment and stone type, there may be a little to a high likelihood of fading. Ask LD for her special kunzite baked in chicken recipe

Kunzite and morganites are notorious faders, and I'm not sure if that is limited to irradiated stones as it seems that I've seen a fair amount of this material which has been heated and fades in a matter of days/weeks after. There was a recent thread about yellow zircon fading after heating (I have not witnessed this, but it happened during the course of the thread as the OP was searching for a stone - I believe it was Yssie who was looking). Like LD, I have not heard of smoky quartz fading and don't know about amethyst heated to turn it the light green prasiolite color. Maybe you'll just have to live on the wild side, get some, and wait to see what happens. I know its not the answer you seek but I don't think there is a definite answer to your question.

ETA: I realize I made it sound like kunzite and morganite consistently fades; there is stable material as well. It just seems like its often the super saturated material that fades with time.

 

[Jambalaya]

Thanks for the replies. Tiffany sells green quartz. Would that be the colorless quartz which is gamma-radiated and heated? Or are there other ways of greening quartz? (Because I don't think green quartz occurs in nature).

 

[MollyMalone]

OK, so if my stones are gamma-radiated and heated colorless quartz, does this mean that they are they not prone to fading? Is it the prasiolite (which is created from heating low-quality purple amethyst until it turns pale green) the one that's prone to fading?
I couldn't be more confused at this point.

What I meant to convey earlier is that I couldn't readily find anything meaningful about either type of so-called green amethyst. But just saw a January 2015 Rapaport Magazine article that says those that have been gamma-radiated and then heated don't fade. No attribution cited, however, so the source of that tidbit is a mystery.
http://www.diamonds.net/Magazine/Article.aspx?ArticleID=50098&RDRIssueID=132

I don't know if we consumers can readily ascertain whether a particular piece of green quartz is a heat-only product vs. radiated + heated (think it's safe to assume that none of the jewelry we see offered has the rare, "for real" natural prasiolite). Or if, e.g., Kiki McDonough and Tiffany & Co. know exactly what they are selling. I'd say since you like the pieces you've purchased, wear them -- but not while sunbathing

 

[Jambalaya]

Thanks for the input and the article. OK, it's becoming clearer. Green amethyst (prasiolite) comes from a violet or clear quartz which is related to the amethyst family. The green color is achieved either by just heating a type of low-quality purple amethyst; or using clear quartz plus gamma radiation and heat; or using clear quartz plus nuclear radiation. Since the type of purple amethyst that turns green with heat is only found in limited locations, the other two treatment methods of clear quartz I just described probably account for most "green amethyst" on the market today.

Is that a fair summary?

I'm thinking that the expensive brands like Yurman, Tiffany, Kiki McDonough must surely use the clear quartz plus gamma radiation and heat, since that combo of treatment is apparently the most stable. These brands sells many, many thousands of pieces per year,and they operate in hot countries, too. If the color of their green amethyst faded, surely they would have a big problem.

Thanks to those who have replied and for the resources posted. I'd be interested to hear any further thoughts.

Molly - I really do adore my green amethyst pieces, and although some of them were very cheap, I just love them and don't want them to fade! Definitely won't wear them on the beach. My Kiki green amethyst drops weren't exactly cheap, though, and I've had some wild thoughts about getting one of the more expensive pairs of Kiki green amethyst earrings some day. But perhaps I'm better off with their lavender amethyst, which I adore too.

 

[Jambalaya]

ETA: I realize I made it sound like kunzite and morganite consistently fades; there is stable material as well. It just seems like its often the super saturated material that fades with time.

Then that would explain the fact that Kiki McDonough's morganite is so pale it's almost white. When Kate Middleton wore Kiki morganite drops I would have had no idea that they were pink - they looked clear (although pinker on the website). If they are not saturated with color to begin with, then they won't fade if the bolded above is correct.

My local jeweler has a lot of pink kunzite in a flat case with a lot of lights. The same items have been there at least a few months and don't seem to have changed. But again, they are pale pink, not a saturated, intense hue.

In addition, the GIA article I posted above also says that pink kunzite doesn't fade.

 

[arkieb1]

I've had a small amount of Kunzite that faded and most that didn't at all so I suspect it all depends on the treatment it has had. A lot of quartz I have seen is dyed not just heat treated, a lot of cheap brightly coloured stones and beads from Asia are dyed and it fades over time and the colour also can leech out of it too when various chemicals go near it.

 

[minousbijoux]

No, my point is that I see a fair amount of very saturated morganite and kunzite being sold by FB vendors. When pressed, they will say that its been heated recently and will fade but they don't disclose that fact up front. I was trying to say that now when I see too good to be true morganite or kunzite, I avoid it because I'm pretty sure, unless its phenomenal quality with a price tag to match, that it will quickly fade.

 

[MollyMalone]

* * * My local jeweler has a lot of pink kunzite in a flat case with a lot of lights. The same items have been there at least a few months and don't seem to have changed. But again, they are pale pink, not a saturated, intense hue.

In addition, the GIA article I posted above also says that pink kunzite doesn't fade.

Perhaps it's UV rays as in sunlight, not a jeweler's display lamps, that are more problematic?

Dr. Nassau had a great reputation, but I'm kinda leary about relying on his JCK article (think that's what you meant to type) because it's nearly 20 years old. So we may be seeing mined stones that aren't of the same kinds (origins, composition, and/or treatments) than what were commonly peddled back then, or synthetics that weren't in the marketplace at that time. Additional and better info may also now be available. As of now, GIA is saying, Whether natural or enhanced, the color [of kunzite] can fade when exposed to heat and intense light. It’s a good idea to store kunzite jewelry in a closed jewelry box or case when it’s not being worn.
http://www.gia.edu/kunzite-quality-factors

 

[Luke76]

Hi Jambalaya,
Chelsea filter might be useful to separate heated vs irradiated prasiolite
here the link:
http://www.geohavens.com/index.php?option=com_content&view=article&id=202:prasiolite-green-amethyst&catid=95&Itemid=586

ciao!

 

[Jambalaya]

Thanks for all the useful replies, everyone.

I love the stone and it's also inexpensive, so I don't care how many treatments it's had as long as it doesn't fade.

I considered buying a Chelsea filter but even if the stones show up as radiated, I still wouldn't know if they are prone to fade because I wouldn't know if they had been heated after radiation. (The Rapaport link posted above says that radiated stones are stable if heated afterward.)

I'm none the wiser. I'm just going to continue buying and enjoying green amethyst and assume it won't fade. The Rapaport article says that the most popular method of greening quartz is gamma plus heat to ensure non-fade, so I'll assume that applies to most green amethyst, especially the expensive designer stuff.

 

[stracci2000]

I had a beautiful 5 ct. hiddenite fade from minty green to colorless as it sat on my worktable for a few months.
When I finally picked it up to work with it, it was no longer green. It is still beautiful and sparkly, but colorless.

 

[Jambalaya]

Sorry about your stone, stracci!

 

[Jambalaya]

It seems that most green quartz that is radiated is also heated to stabilise the color. After all, what would be the point of doing one and not the other, as fading stones are bad for business. I think all this stuff on the internet about green amethyst fading is scare-mongering, probably coming from the fact that it can fade if the treatments aren't done correctly. The heating of low-quality purple amethyst from a certain location which results in greened amethyst is stable, and the radiated stuff is stable as long as it's heated too.

 

[LD]

Ok - here's your problem ............

9/10 times, sellers won't know if a stone has been irradiated or not. So you can't rely on that. Those who are selling the gemstones don't really care whether they fade or not so they don't try to stabilise anything because it's an added cost. Clearly you have different suppliers who do different things but typically as the end user, trying to find out what's been done to your stone with any reliability is slight unless you're buying direct and/or have a reliable source and/or can have the gem tested prior to sale.

Next, even if the stone has been irradiated, there's no sure way of knowing whether it will fade or not. Some will / some won't.

Kunzite is a notorious fader. In some cases it fades quickly (with or without sunlight), some will fade with constant wear and exposure to sunlight and some won't fade at all. It's one of those gems that you take on a chance on - a bit like Russian Roulette for gemstones.

A few years ago, I took a faded Kunzite and re-heated it (inside a chicken) in my oven to see if I could get it darker. It did go darker by a shade or two. I now have a kiln so may experiment getting it to a darker colour with that.

Pictured below is a 24ct hiddenite I have. This was emerald green when I bought it - as in the photo. Within a month it had turned minty green and another month later it was clear without any hint of green. This gem had been treated to the eyeballs because when it arrived it smelled of petrol so I have no idea what had been done to it!

 

[chrono]

9/10 times, sellers won't know if a stone has been irradiated or not. So you can't rely on that. Those who are selling the gemstones don't really care whether they fade or not so they don't try to stabilise anything because it's an added cost. Clearly you have different suppliers who do different things but typically as the end user, trying to find out what's been done to your stone with any reliability is slight unless you're buying direct and/or have a reliable source and/or can have the gem tested prior to sale. Next, even if the stone has been irradiated, there's no sure way of knowing whether it will fade or not. Some will / some won't.

+1.

 

[Jambalaya]

Thanks, both.

LD, you cooked your stone inside a chicken? That's hilarious!

Kunzite is a notorious fader, yes, but the same doesn't seem to be true of green amethyst.

 

[PieAreSquared]

Those who are selling the gemstones don't really care whether they fade or not

If this has been your unfortunate experience, it sounds like you are buying from the wrong people.

 

[Jambalaya]

I really would have thought that fading gemstones would be very bad for business. Wouldn't customers come back and yell at them? Especially ones who'd paid many thousands for designer items!

Somewhere in the links posted above it says that radiated gemstones are usually heated afterward to make them stable, which makes sense to me. If a jeweler had the experience of gemstones fading, I'd assume they wouldn't buy from that supplier again. I believe that if you make bad goods, eventually that comes back to bite the maker in the ass.

 

[LD]

Those who are selling the gemstones don't really care whether they fade or not

If this has been your unfortunate experience, it sounds like you are buying from the wrong people.

I don't mean to be insulting, but your comment is a little naive. The problem starts with the person who buys the stones from the miners and then treats them. They are then widely sold to a myriad of suppliers. You cannot tell by looking at a gemstone whether it'll be stable or not - testing also won't tell you that. In fact, the people doing the treating might not be able to tell you that either. Up until about 10 years ago, irradiation of gemstones wasn't commented on much and many "natural" gemstones were actually being irradiated without disclosure. Rubellite for example. Irradiation can occur naturally and therefore it was quite overlooked and when the labs discovered that Kunzite and Rubellite were being irradiated it divided opinions as to whether this was acceptable or not. So, I'm not sure who the "wrong people" are but since you cannot be guaranteed that fading won't occur there's no "right people". The Kunzite that faded on me was from the same supplier that sold me Kunzite that hasn't faded (yet)! Like I said earlier, it's Russian Roulette.

 

[LD]

I really would have thought that fading gemstones would be very bad for business. Wouldn't customers come back and yell at them? Especially ones who'd paid many thousands for designer items!

Somewhere in the links posted above it says that radiated gemstones are usually heated afterward to make them stable, which makes sense to me. If a jeweler had the experience of gemstones fading, I'd assume they wouldn't buy from that supplier again. I believe that if you make bad goods, eventually that comes back to bite the maker in the a$$.

I can't see, logically, how heating after irradiation will guarantee a non fading gemstone. Heating occurs naturally in the ground so therefore the stone will have been subject to intense heat before it was mined (that's part of the growing process for a stone).

Kunzite has been sold for years and has been known to fade for years. I have no idea if people have complained if a stone has faded but it's part of being a collector that you know these things can happen - just like you know that over time an Emerald might need oiling, or an Opal may need some moisture to stop cracking.

 

[PieAreSquared]

I don't mean to be insulting either, but your comment is (more than) a little dogmatic.

I was referring to the part of your comment I quoted, "Those who are selling the gemstones don't really care whether they fade or not". How are you able to say unequivocally that no sellers of gemstones care what happens after a sale? If that is the kind of seller you deal with, that is unfortunate.

I am very well aware that it is next to impossible to trace a stone and all its possible treatments from the ground to the consumer, that is not what I was disagreeing with.
Of course, many dealers are unscrupulous and don't care what happens after a sale, but not all, and that is what you seemed to be implying with your broad statement. If that is not what you meant, I apologize, that is what it sounded like to me.

 

[Jambalaya]

Surely the supply chain can't be quite as opaque as all that, LD? If you are a jeweler, and you don't know where your blue topaz comes from, for example, you could end up unwittingly selling jewelry that's radioactive. You wouldn't know if it had sat in storage for long enough.

I have some very cheap pieces set in silver and I wouldn't be surprised if those cheap sellers don't know where their stones come from, but if you are Kiki McDonough and you are selling a pair of green amethyst earrings for seven thousand dollars, I bet she knows exactly where her stones come from and what's been done to them. A savvy business person like her just wouldn't take the risk otherwise- same with Tiffany's green quartz. I find it very hard to believe that these mega-bucks top-luxury brands with everything to lose and nothing to trade on but their reputations don't know where their stones are from or what's been done to them.

On the other hand, maybe I'm just naive and maybe they really don't ask any questions or have a clue where their supplies come from. Maybe the green amethyst in my super-cheap ring is the same as the green amethyst in a Kiki three-thousand-dollar ring, in which case they're all bandits.

I do find that the milieu of colored gemstones is a world of pain. No matter how much research I do, I always seem to end up feeling upset and disappointed somehow. At least gold, silver and diamonds are what they are!