Prasiolite green amethyst

Hi all - I hope someone can help me answer this once and for all as I keep getting conflicting information on the subject. I have searched the message boards and have not turned up this question as already answered, so I do apologize if this has already been addressed in the past. *is* green amethyst heat treated or naturally pale sage green? I have been told by various sources in gemstone dealership that it is a) ordinary amethyst mined in brazil which turns green when treated with heat and *never* occurs naturally as a green stone and b) that prasiolite is an entirely natural green stone which is pulled from the earth already in possession of this ethereal light green colour. On all accounts, however, I am told it is mined in Brazil and i have not heard of other sources for this stone. A further question - if green amethyst is natural and not heat treated as standard, why is it called green amethyst and not simply referred to as green quartz or some other name that doesn't make it sound like a derivative of a purple stone? I haven't been able to find references for prasiolite or green amethyst anywhere on mindat. thanks for any help and information you can offer.

The green amethyst is heat treated amethyst that turns green. The green color can also be caused by irradiating some quartz. There is also some naturally occurring green quartz (prase, etc).

[www.minsocam.org]
[www.gaaj-zenhokyo.co.jp]

Hi Freya

This question has come up before, and the answer is that the material is not natural - the color is achieved be heat treatment.

It should also be noted that "green amethyst" is a misnomer, since the definition of "amethyst" involves its color. Any other color can not, by definition, be amethyst. It is best to call it "green quartz created by heat treatment of amethyst." Or use the marketing term "prasiolite." Just be advised that "prasiolite" is not a mineral name that is accepted by the IMA - it is a marketing term only.

Regards

Alan

thanks for the replies - i was pretty certain prasiolite was an artificially achieved stone (colourwise), but i have suppliers (i am a jewellery designer) who are adamant that it is natural and there have been a few rather heated arguments on the issue. and it was always my feeling that calling it 'green amethyst' was about as sensible as calling it 'green citrine', etc. i am aware of naturally occuring green quartz and was of the opinion that it was not synonymous at all with prasiolite. i greatly appreciate the clarification of the issue. best to all ~

How can Amethyst be green? Amethyst must be purple as far as I'm concerned although there are a great number of so called experts out in the western part of this country (U.S.A.) that call any Quartz Amethyst if it has the slightest bit of color.

Joe D.

Yes, I am for clear, logical gem/mineral names too, but the marketplace -- and some well-meaning collectors and miners -- can make things confusing. And now we're seeing the crazy name "black amethyst" used for very dark quartz crystal clusters!

There is one article I'm aware of on naturally-occurring green quartz crystals. I just found this summary on the GIA website:
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[www.gia.edu]

Gems & Gemology [the quarterly magazine of the Gemological Institute of America], Spring 1982. Volume 18, Issue 1, pages 39-42. (sold out)

"The Natural Formation and Occurrence of Green Quartz"
Thomas R. Paradise

"Amethyst may develop into the more common citrine and rarer green quartz naturally under certain geologic conditions. On the California-Nevada border, just north of Reno, amethyst, citrine, and green quartz do occur together in clusters of crystals in detritus. These crystals, found lying loose in rocky and sandy rubble, appear to have eroded from cavities and vesicles in the inaccessible cliffs above. The quartz was deposited in these spaces by the slow accumulation of silica from migrating solutions. Low-grade radiation over a geologic time span was responsible for the alteration of the ferric and ferrous quartz into its amethystine color. Secondary, high-temperature, extruding volcanic bodies are believed to be responsible for the subsequent color change to citrine or green quartz."

I'm not sure I've ever seen specimens of this green quartz, and I pay attention to California quartz; it clearly has never been a factor in the commercial market for either specimens or cutting rough. It probably is as rare as the abstract above says. It is certainly dwarfed by the smoky qtz & amethyst production of the well known deposits nearby at Hallelujah Junction.

I have the article in front of me, and the one picture given of the green quartz is of a faceted stone that is quite pale.

BTW, Gems & Gemology has a 25 year index online, and sells back issues of its award-winning, beautifully illustrated magazine -- though apparently they are out of stock of this issue.
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To confuse things further, there is the old term "prase":

[www.mindat.org]
PRASE - A variety of Quartz

"Originally, the varietal name "prase" was applied to a dull leek-green colored quartzite (a rock, not a mineral); but over the years it has been also applied to other materials, particularly a green colored jasper of similar color. For perhaps more than a century it was restricted to granular micro-crystalline varieties of quartz and the original quartzite; but in recent years euhedral crystals of quartz having a similar leek-green color have had the term applied to them as well, expanding the definition beyond micro-crystalline forms. Now it is simply a color descriptor for quartz: If it is leek-green, it is called "prase" - whether it is micro- or macro-crystalline, and no matter what causes the color. Basically, the term no longer has any scientific rigor - it has become a general term; it can't even truely be called a varietal name any longer - since it covers more than one material."

Good Luck out there!!

Rob

To make matters worse, there is a natural material, sold as 'green Amethyst' which is ... green (sortofish) Amethyst! Amethyst (usual purple stuff, rarely very good colour) from Farm Rooisand in Gamsberg, Namibia alternates with greenish Quartz. The separation of green and purple zones is rarely distinct.The locality is descibed in:

Jahn, Steffen; Medenbach, Olaf; Niedermayr, Gerhard & Schneider, Gabi. 2000. Namibia, Zauberwelt edler Steine und Kristalle, Bode Verlag GmbH, Haltern

Claus

____________________________________________________________________________
Claus Hedegaard
[www.Natureshop.dk]
[www.Hedegaard.com]
Strandvejen 2a, 8410 Rønde, Denmark

no wonder definitive info is elusive...there seems to be no airtight consensus!

Ok, so would the same hold true for Amegreen which is a visual combination of purple amethyst and green "prasiolite"? How does one heat treat one area and leave the other purple? I know that sounds a bit silly, so I want some clarification thanks!!

My guess would be they found that if they stopped the processes soon enough some areas of the material would have turned green while others remained amethyst in color. I believe someone noted above that the green-purple combination has been found occurring naturally from a locality in Namibia.

Keep in mind that even a crystal that looks like it is all one homogenous material may not be - there may be zonations and/or areas containing different concentrations of inclusions and/or radiation-induced color-center shifts.

Mother Nature loves nothing better than to throw curve balls!

:~}

Alan

do you have a link as to where this green/purple amethyst combo could be viewed? i would love to have a look just to see what it's like. sounds like it could be quite interesting.

Ok, so let me see if I have this right:

Prasiolite is actually green quartz. (Mine comes from Malawi. That is what I was told.) Prasiolite, also identified as "Green" Amethyst, cannot be Amethyst and be green at the same time. Correct?

Amegreen, which is a combination of purple, sage green and sometimes white quartz, all mixed into one is.......what exactly? Is it all heat treated? i have to be honest, i have looked at the tumbled pieces I have and there is no defined area of color change.

So technically, Amegreen is a combination of Amethyst and green quartz. And since amethyst is a type of quartz, it could be generally identified as tumbled quartz or bicolored quartz.

Now to throw something else into the mix.....many of the tumbled pieces I possess have obvious white chevrons that appear to be naturally occurring. If all of this stuff is heat treated, how would the chevron area not be affected?

I gotta say, was trying to get a simple answer for myself and a customer, but now it appears rather confusing with no one answer this is very frustrating ) But i will keep going until i "get it".

thanks everyone for the help.

The green amethyst is probably more properly called greened amethyst. The green color is usually caused by heating of amethyst (natural or artifical). The white quartz (milky) color is caused by numerous fluid or gas inclusions in clear quartz - they could also overwhelm an amethyst color. These will tend not to be affected by heating (unless for a long period at very high temperatures would allow the migration of the inclusions - not very likely to happen).

The term Prase (in Italian Prasio) had been used (and is always in use) by Italian mineralogists for a green variety of quartz, tipically from Elba Island (ref. F. Millosevich, 1914) in the Torre di Rio skarns (the TL of Ilvaite).
Exact locality is Porticciolo (3 km from Rio Marina), and is associated with hedembergite. More recently (1992) I have found pale green quartz in the Rio Marina Mine, Valle Giove pit, with habitus and colour different from Porticciolo prase. I have alsoo checked the presence of prase in Calamita Mine when was active; this last was generally non trasparent.

Hi Kristi

I'm sure that by now you see the craziness of tagging things with various non-technical names willy-nilly. A mineralogist would, indeed, call a bi-color quartz just that: "bicolor quartz" - and thus avoid all the confusion. He/she would call "prasiolite" a made-up name with no scientific validity - a marketing term intended to sell something for more money than it would fetch if it was labeled "green quartz" or "bicolor quartz", rather than to identify it in any scientific fashion.

The same can be said of a great many of the names that have been hung on previously identified species in recent decades - names intended to "distinguish" things so they sound more valuable than what they actually are.

I think that the best thing any dealer can do these days to help the science is to simply make sure that a mineral label (or a label on a piece of jewelry, etc) states the species name FIRST; and then - maybe, if really warranted - gives any varietal or marketing name in parentheses, and in quotes. That way the public will become better educated about what these things are that they are buying.

It seems to me that this is what you are trying to do - and I applaud you for it. The difficulty you face is sorting out what is a legitimate species name, and what are either varietal names or marketing names. And - quite frankly - you couldn't find a better place to help you dope things out than right here at Mindat. So keep on asking questions - but don't let the confusion surrounding some of this stuff get you confused. Focus on what SPECIES something is - and simply recognize that any other names for it are so much fluff.

:~}

Alan

Hello, everybody,
due to my work as a gem salesperson, I have been asked to do a work about the prasiolite, which, like you all mention, which I assume is the correct version, is a greened amethyst.It turns green at a temperature of 932 degrees F.It gets its name from the leek-green colors it achieves, and comes mostly from the Montezuma Mine in the state of Minas Gerais, Brazil.
Then there is also the "praseolite", an equally leek green stone of the cordiorite family. Please refer to the article written by Edna anthony, in the New Mexico Facetor. You´ll find all questions answered there.

Hi,

I am looking at buying a necklace for my girlfriend for her birthday and it has lead me to try and find out exactly what Prasiolite and Green Quartz are.

The neclace im looking at is this:
[www.pajewellery.com]#

Could anyone confirm for me is this naturally occuring Green quartz and not some artificially created gem.
I have been un able to find anything on the net which demonstrates this same deep dark green colour, any info on this? Is this colour rarer ??

Very much appreciate any input/advice

Thankyou )

ah, it didnt like the link I posted, u can pieace it togethor from this im sure

http:// www.pajewellery.com/productDetails.aspx?productID=556&giftIdeaID=5#

Hi Alex

It is impossible to determine whether or not it is natural from just a photo - especially when there is no information about what mineral locality it came from.

The odds, though, are that it is artificially colored. Naturally occuring green quartz is rather rare. "Color enhanced" quartz is rather common...

Regards

Alan

Besides enhanced natural quartz, there's a lot of synthetic (autoclave grown), colored (any color, even zoned) quartz available now. And there are no other apparent uses for this material.

To make this worse, we have a locality south of Butte (Montana USA) that produces a fine, transparent quartz with minute inclsions of amphibole that colors the quartz a nice green!

And for something more in the mix...kinda pretty, if nothing else. If you do a search on eBay right now, it will turn up--item # 330020627070.

Cheers!

>^..^<

Susan

I did - and ended up with a locked screen. I don't know if it was just my computer , a glitch with the Mindat server, or the fact that the image is a .bmp file - but until one of the management team says it's safe I'd recommend you not try to view the picture.

Alan

A well known mineral collecting locality in Queensland Australia, known as Castle Mount, South of Cloncurry has been regarded by many as an amethyst locality. When I visited there I found not only amethyst - yes a very deep purple, but also around different parts of the locality a quartz material in crystal form that had zonations of purple - then green - then purple - then white etc and in different parts of this locality again crystals of quartz that were of a lime colour. Nature again throwing up a conumdrum. Some further information or research maybe helpful.

An interesting discussion. As I recall, the color of amethyst is due to color centers--defects in the crystal that trap electric charge and absorb light in specific ranges. The charge gets trapped because the trapped state has lower energy than the untrapped state. However, if you add energy, you can free the charge, and the amethyst no longer absorbs light in the same wavelength region. This is called bleaching. Different traps have different energy depths--that is they need different amounts of energy to become bleached. In amethyst, the color centers that result in a green stone require more energy to bleach than those that make the stone purple. So heat the stone, and you get green quartz. Heat it even more and you get clear quartz.
Now, how would you restore the original color? You would have to expose the former amethyst to ionizing radiation--UV, x-rays, protons, electrons...radiation that will generate charge that can subsequently be trapped by the defects to give the purple color again. The color of fluorite is also due to color centers.
Note that not all heat treating is done to liberate charge from color centers. With sapphires, you are actually changing the ionization states of impurities in the crystal (e.g. iron and titanium) to alter the absorption properties of the gem. The whole story of color in gemstones is a fascinating one.

If you would like to see some excellent photos of this gem go to JTV.com. They have over 150 different prasiolite stones of many different sizes and cuts. They have said that prasiolite is found naturally (in small amounts) as well as treated. The prices are very reasonable and should help you put a value on any you might have. These are all facited clear gems. Their staff has many experienced gemologists not only as buyers but as show hosts. They have an excellent reputation, and are the largest seller of colored gemstones in the world. They do all of their buying for cash up front and buy in large quanities. We have just found them an excellent source of gem data as well as quality gem stones.
We have bought many gems from them with excellent results, but also buy from other sources, but use JTV's site to get most of our pricing info before we buy from others. They also have available an extensive library of gemological data you can search on line.
Some of this gets away from prasiolite but I hope can be helpfull to everyone as another scource of information.

Harry

The question in my mind regarding JTV is: Do they state up front whether a gem is in its natural state (other than the fact its cut) or has it been altered/treated/enhanced in any way?

I happened to catch a bit of their show once at a friend's house and, at that time at least, the answer was "No." That effectively ended my interest in the outfit: Others may not care whether or not the gems they buy have been "enhanced" in some manner (again, other than cutting) but I do.

Alan

I have a crystal from Canada, looks natural to me. The base is Amethyst then goes green. HEre's a pic. Could this be treated ? From Canada.

Aymeric,

I suspct that if you examined a small chip under the microscope, it is very likely that you would find that the greenish tint in the quartz is due to tiny inclusions of some green mineral, perhaps clinochlore or similar.

Pete N.

Dear Sir,
I am Nazmi Raheem from Sri lanka. I need some information about Malawi gem stones and mining placess in Malawi.Thank You.

Hello Nazim

Use the mineral locality search engine here at Mindat to look up localities in Malawi. Just type "malawi" into the window and click "Go". You will get a menu of all the localities in Malawi that have been entered into this database so far. You can then click on individual locality names to bring up the information for each site.

Regards

Alan

A pair of attractive earrings "green amethyst with brown diamonds" attracted my attention to the subject of green amethyst. If green amethyst" is praseolite, then the seller makes a whacking profit considering the price of praseolite.
The seller of the earrings insists it is green amethyst from "somewhere" in Africa.
these earrings. The jeweller is a gem dealer as well. Who to trust???

Mineralogist?

:~}

This issue of Prasiolite-Amethyst-Green Amethyst-Green Quartz is very confusing. I have a supplier in thailand who claims "Green Amethyst" comes from Russia and untreated. Although this might be suspect, the gemstone is beautiful especially the flawless one's I've acquired.

Marketing strategy might have made this "issue" more confusing than helpful. I decided I will collect them since they are a pleasure to work with...I design jewelry for a living.

"Tinno" Artist, Boston, MA

Samples of my work may be viewed by visiting: www.helloboston.com/art/tinnoCFM.cfm . Jewelry designer, Poet(published), Photographer(published), Traveling Private Chef.

Hi. I am looking at a cushion cut prasiolite about 1/2 inch, descibed as clear, minty green. It is surrounded by a pinky/peach border of morganite. The asking price is about 350.00. I always read what you all have to say and after reading this thread I am sceptical regarding this purchase. What are your thoughts. Any and all input would be most appreciated. Thanks

Just to add one non-technical observation - at the last Bangkok Gem show a couple of suppliers had kilos and kilos of rough "green amethyst " if i remember right about 1US gm.From what I've read here clearly not natural.

? heat treated amethyst or synthetic ?

I was told that if you heat Amethyst over 500c it turns into citrine, but this particular amethyst from Brazil turned Green because it had different inclusions.

If it started off as Amethyst I see no problem with calling it it green Amethyst - the market has chosen, resistance is useless :->

But I'm really concerned with how a 100 kilos say of " green Amethyst " chunks with very consistent colour could be produced so I can at least tell my customers the truth ( and maybe buy some for cutting next time)

My first post here, thanks to all other contributors

There is plenty of 100% synthetic green quartz coming out of China and Russia, while some of this green quartz being sold for cutting may well be heat treated amethyst there is the possibility that some of it is entirely synthetic.

The chances of any of it being 100% natural are small. Naturally green quartz just isn't that common.

And the name "green amethyst" is just hideous. It's just as bad as that other nonsensical name "red emerald" for the red Utah beryl!

Jolyon

Aymeric - your anhedral crystal from Canada - I'm not seeing any green in that pic.

I've heard rumors of some green quartz coming from the amethyst mines of the Thunder Bay, Ontario region, but I've not seen them, and I remain VERY skeptical. I'm pretty sure I've seen all the relevant literature, and don't recall mention of any green stuff. All shades of purple, red tints, colorless, white, yellow shades, and smoky as well, but have yet to see green. Unless I bought it from a mine owner that I know personally, I'd assume that the piece found its way into a bonfire one evening, or perhaps some jewelers furnace.

As for the horribly named "prasiolite" - well, it's been known to be heat-treated Brazilian amethyst for at least THIRTY YEARS NOW. Grats to the jewelry trade for making very, very simple stuff so damn confusing to the general public. Honestly, you'd think these wannabe gem experts were building their careers on defrauding the public instead of actually informing the public.

I know a tiny bit about football, and would hence never be hired to do TV commentary on football games... but if you know a tiny bit about gems, you get hired to sell gems... and WRITE ABOUT GEMS IN TRADE MAGS OMFG... end of rant.

(I'm a mineral guy... this stuff drives me up the wall, ok.)

Tim Jokela Jr

Tim et al,

I've collected amethyst often near Thunder Bay and have occasionally found green quartz there, though not in well-developed crystals. I was told by proprietors at two mines (the "new" Diamond Willow and the Amethyst Panorama or whatever - the big mine on top of the hill, not on the Pearl Lake Road) that sometimes green crystals do occur. In my youth I found green crystals of quartz associated with botryoidal goethite in a stream in a park in or near Silver Spring, Maryland.

I don't assume that all green quartz is colored by inclusions of other minerals, although some well-known localities do show this - with hedenbergite (i.e. Serifos, Greece), clinochlore (phantoms from many places), etc. How does it make sense for amethyst in a bicolored piece to get its hue from color centers associated with iron substituting for silicon in the crystal lattice, but for the green quartz next to it suddenly to change to a totally different mode of coloration?

I either remember or hallucinated reading something by Kurt Nassau about quartz colors that cited differences based on whether the iron substituting for silicon was ferrous or ferric. Presumably, heating amethyst that contains ferric iron turns it to citrine, with a color consistent with the yellow-orange-red-brown hues of many minerals with ferric iron as a chromophore. Amethyst with ferrous iron would likely turn green after heating; many ferrous iron-colored minerals are green. I think Nassau actually mentioned the term "prasiolite" in that publication.

As for natural bicolor quartzes, nobody seems to have a problem believing in "ametrine" so what is the big conceptual beef with purple and green coexisting in quartz? Perhaps variations in iron concentration, presence of other impurities, or some effect of different growth zones in the quartz crystal (i.e. Brazil twinning) affect the ease with which color centers can be created by ionizing radiation.

All that being said, it's still unethical for sellers to deceive their customers about whether the gemstone or mineral specimen they are purchasing is natural, treated, synthetic or even genuine. If you want to see a stunning example of total deception, go to eBay and search for zircon in the mineral specimen category and see what the Chinese dealers are selling!

Bill Barr

Hi Alan and everybody else.

I am a Gemmologist, and I recently saw an advert in one of our national newspapers here in the UK, The advert was for "Green Amethyst"???
This prompted me to write to the firm concerned to explain to them that they could be prosected under the trade descrition act if they continued to call the gemstones for sale as "Green Amethyst". Two weeks later I received a reply from the firms lawyers telling me that, if continued to threaten them with the trade description act they would see me in court for "defamation of carachter"! I wrote to the firms lawyers ponting out the finer points of the trade description act when it came to selling gemstones etc, etc. This week I noticed that the advert had been revoved and I still havn't had a reply from their lawyers?
Spencer.

Excellent work Spencer!

Jolyon

The more correct term to use would be greened amethyst as the color can arise when some amethyst is heated. Natural material is known from Nevada (subsequent extrusions of a basalt heated up pereviously depositted amethyst) and the Thunder Bay Region (Can J Earth Sci 1993 30:1955-1969).
The color comes from interstitial Fe²⁺

For those interested in the color of quartz the chapter by George Rossman on the colored varieties of quartz (MSA's Reviews in Mineralogy vol 29 Silica) is the best article available.

I'm sorry, there is no green amethyst. Amethyst is the purple color of quartz, just as ruby is red corundum and emerald is green beryl (due to Cr or V). These names date back to antiquity and have a long history. I will buy a "green amethyst" about the same time I buy a blue ruby.

Go to dirtyrockhounds.com and ask?

I am somewhat familiar with the green quartz gem that is pictured in the G&G article having held it in my hand (and exhibited it at the Denver and Tucson shows). It is now in the Houston Museum of Natural Science and, before that, was in the Jim Houran collection. It is by all accounts natural and yes, rather pale. I have not seen and crystals of the material but am told that only a bit of gem rough was found.

The January/April 2007 edition of the British Journal of Gemmology has an abstract of an article appearing in the German magazine Gemmologie, Z. Dt.Gemmol. Ges., 55(3/4), 2006, and I quote - " The amethyst mine of Montezuma in the northern part of the Brazilian state of Minas Gerais produces amethyst which can be modified to green by thermal treatment, the so called prasiolite."

Incidentally, the occasional broken geode of transparent green quartz crystals can occasionally be found at Agate Creek, in North Queensland. Amethyst geodes are rarely ever found on or near the surface, I presume due to the extreme tropical climate during summer. Most geodes found on or near the surface are in shades of citrine, smokey citrine, or lemon citrine, with the green crystals being found occasionally.

I have also found transparent tri-coloured quartz there, in colours of purple/colourless/citrine, but so far they have been only very small crystals.

Ok so i know that this issue is being beat to death but i am researching this so-called "green amethyst/prasiolite/prase/whatever... just green quartz, because i found one about two days ago outside of my home. I often find amethyst usually in crystalline form. Two days ago i stumbled across a very lightly colored greenish quartz stone. The coloration is consistent with so called man-made prasiolites. I believe that if natural occouring amethyst can be turned green due to applied heat then natural prasiolite can be made by amethyst being exposed to high temperatures within the Earth's crust after a crystalline structure has already been formed. I would say that most of your commercial grade stones are artificial due to the fact that "green quartz" is rare. I also think that reapplying heat naturally would cause most natural crystals to crack and cause it to be very flawed such as the one I found. I would say that both natural and non-natural green amethyst occur, but most gem quality stones are probably synthetic.

Amethyst as a description of colour implies something within a specific colour range of deep purple to pale lilac or mauve. In terms of mineralogical colour the variations have points where the tendency is for one colour to posses intimations of another colour as with the amethyst-smokey quartz crystals from Namibia. The differentiation is quite clear as the crystals often contain both.The question for me is, "Is there an accepted criteria that defines such a coloured variety of quartz as "Amethyst"? If not perhaps there ought to be as a quartz crystal that is coloured green is hardly a form of amethystine coloured quartz but a variety of green coloured quartz. Why complicate matters with such inaccurate descriptors? Find a more sophisticated and accurate terminology.

*is looking at natural green quartz right now*

Hi All,

I'm a newbie 'round here, just come across mindat and I've been lurking around the site for most of the day, but I just saw this thread and felt I had to post.

I'm a Geo student from Australia and last year we went on a geo-society field trip to Broken Hill. We did a hell of a lot of mineral collecting on the trip but one of our stops was an Amethyst location.

Now let me tell you I have never seen so many quartz crystals in all my life (small ones though, about 2-5mm generally). Most of the samples we collected there were mixed green, white and purple quartz.

Now our lecturer told us that the green was due to exposure of the amethyst to sunlight. I haven't done any research into the matter, but I have no reason to doubt him. He also told us that he'd left some of the purple quartz on his windowsill and it had turned green, then put in in a shoe box and chucked it under his bed and waited to see if it turned back...that was 20 years ago and it's still green ;-)

Anyway, we were probably a little bit hung over at the time and I can't really remember the reason for this colour variance, other than it did have something to do with the iron content (it could be the ferrous vs ferric argument, not sure); this also affected other minerals in the area with a green hue (though the ones we saw were from diamond core in fresh rock rather than surface rock).

Having said all that I do have a piece which not only has quartz crystals of white, green and purple hues, it also has on one end very dark smoky crystals.

So my answer would be yes, it does occur naturally. Odds are though, it's probably artificially produced, that's my feeling anyway.

And just to add my two cents, I don't like the term "greened amethyst" any more than "green amethyst". I think the more appropriate term would be "heat treated amethyst". But that's just me.

If I can dig up the piece I'll take some photos and post them, but I've just moved house and most of my stuff is packed (apart from the small piece that's sitting on my desk as a paper weight :-P )

Anyways, hope that sheds some light on the matter and makes it even more confusing LOL ;-P

Cheers,

Kit.

Information from GIA

Few natural occurrences of transparent green quartz are known. Most quartz of this color is a result of heat treatment. Green quartz, whether natural or treated, is sometimes called PRASEOLITE.

In my opinion, green amethyst is heat treatment of quartz. so it is different from natural green quartz. but we call also call green amethyst as Praseolite.

Cheers,
Pimmy