Is it true that green amethyst fades?

[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 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.

Well, I don't know the science of it, LD, but here's the quote.

The more popular way to produce prasiolite — and simpler because it does not involve NRC regulation — is by gamma ray exposure in a cobalt-60 irradiator. In this method, the stones are placed in a thick-walled container in which gamma rays move the electrons from their normal positions within the stone. The color change happens as a result of the new electron formation and the charge of the atoms around them. After the treatment, the material is heated so that the color doesn’t fade.

That's from the Rapaport magazine January 2015, which I think should be a reliable source.

 

[LD]

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.

I would NEVER sweepingly say ALL dealers are unscrupulous. If you read the bit I've put in bold you'll see that I wasn't lumping everybody into the bad seller category. I'd never do that.

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.

The people closest to the mines who treat gemstones TYPICALLY are the ones who have less of an eye on the end user. I would trust the lapidarists that frequent this forum because they know their suppliers and will test stones themselves. They have a practised eye and will instinctively know if something isn't quite right. This bring us, the consumer, closer to the supplier than if you buy from a high street jewellers. If you go and buy a stone from the High Street and ask them about provenance TYPICALLY they can't tell you where the stone has come from OR they rely on what they've been told and I would go so far as to include designer stores in that as well. The OP has mentioned that it appears to be inconceivable that a designer, who sells stones for thousands, might sell inferior (fading) gemstones. I agree that the notion is inconcievable BUT you'd think if you walked into Tiffanys that you'd get a first class, high quality product but that's simply not the case. There have been some horrible examples of Tiffanys' stones mentioned on this forum (about 4 or 5 years ago) and it's well worth having a read of those threads if you can find them. Buying a stone from a designer store gives you no guarantee of quality than buying from elsewhere (unfortunately).

I'm not being dogmatic - I'm being pragmatic and speak from experience of collecting for over 30 years. I only mention that, not because that gives me any more credence than somebody who has been collecting for 1 year but it does give me a little more insight into the gemstone world, what has developed over the years, understanding where they come from and what you can expect. In an ideal world, there'd be full disclosure but the jewellery world is a million miles away from that unfortunately and with every year, new techniques are uncovered that are designed to disguise, change or alter the natural product to make it more profitable.

 

[PieAreSquared]

Thank you for the clarification LD.

Although I have been posting here less than 1 year, I am not a newbie or naive regarding colored stones by any means. Quite the opposite. I worked extensively in the gem industry in the early 1990's, before taking a different career path. They are still a beloved hobby to me.
I am glad to see you did not mean gem sellers don't care what happens to their customers.

 

[LD]

Thank you for the clarification LD.

Although I have been posting here less than 1 year, I am not a newbie or naive regarding colored stones by any means. Quite the opposite. I worked extensively in the gem industry in the early 1990's, before taking a different career path. They are still a beloved hobby to me.
I am glad to see you did not mean gem sellers don't care what happens to their customers.

I'm a bit confused - I didn't mean to imply that I thought you a newbie???? The majority of my post above was in answer to the OP and his/her comment about designer stores and the quality of their gemstones.

What you may not know is that I'm dyslexic and therefore sometimes posts make sense to me when I type them but may not be that clear to others reading them so on that note, I'm bowing out of this thread!

 

[arabella]

This is a very interesting thread. Until a few weeks ago I had no idea that any gemstones were prone to fading until Earth's Treasury posted a recently cut kunzite (a very pretty one at that) and there was a comment about how it's an "evening gem" because bright light could cause it to fade. I was like haha!

I had no idea morganite was prone to fading too. Makes me wonder and worry about all those girls with morganite engagement rings Does untreated morganite fade too? Earth's Treasury posted a huge, untreated morganite that is very saturated (well, for morganite) to their Facebook the other day. Learn something new every day!

 

[chrono]

I am more concerned that a morganite engagement ring that is worn 24/7 will be damaged well before it fades, if it is unstable.