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. http://www.mindat.org/forum.php?read,15,38542,38542#msg-38542 Thu, 26 Nov 2009 12:45:12 +0000 Phorum 5.2.8-RC1 http://www.mindat.org/forum.php?read,15,38542,101600#msg-101600 http://www.mindat.org/forum.php?read,15,38542,101600#msg-101600 I am located in Melbourne and have some Amethystine quartz from Queensland that has green section, normally around the base of the crystal. You can have a couple to test if you wish, they are not pretty but it may help in this debate. The material was collected in the early 1960's near Toms Mountain Mt Isa mining district. If you need access to lab equpment while in Melbourne I am sure I can arrange some from GIA to assist.

Cheers

Jon

+61 423 227 292
earthstones@iinet.net.au]]> Jon Mommers Rockhounds Sun, 29 Jun 2008 05:11:37 +0000 http://www.mindat.org/forum.php?read,15,38542,101589#msg-101589 http://www.mindat.org/forum.php?read,15,38542,101589#msg-101589
I will be in Australia for several more months before returning to Africa. I noticed a couple of Aussies (SilicaKitty and Peter Clapp) on here who have some examples of green quartz. I have access to the GAA lab here and if you are located in South Oz or nearby I should be able to solve the queries you have about your stones without a fee.

Fell free to contact me here or via PM.

Paul]]> Paul Stahl Rockhounds Sun, 29 Jun 2008 00:33:20 +0000 http://www.mindat.org/forum.php?read,15,38542,101217#msg-101217 http://www.mindat.org/forum.php?read,15,38542,101217#msg-101217 Alfredo Petrov Rockhounds Wed, 25 Jun 2008 08:27:27 +0000 http://www.mindat.org/forum.php?read,15,38542,100432#msg-100432 http://www.mindat.org/forum.php?read,15,38542,100432#msg-100432 AMETHYST
GREEN
UNHEATED
ORIGIN BOLIVIA
LOUPE CLEAN
Iam a beginner in the gem collecting world, however the loupe clean smells of laboratory, I therefore emailed the seller who is adament that it is not a lab created gem and it is not heat treated, so if any kind gemo out there can tell me what I have purchased, please feel free to let me know ,as well as any other info,
good luck PETER CLAPP AUSTRALIA]]> Peter T. Clapp Rockhounds Mon, 16 Jun 2008 08:52:42 +0000 http://www.mindat.org/forum.php?read,15,38542,96789#msg-96789 http://www.mindat.org/forum.php?read,15,38542,96789#msg-96789
Tim, indeed the color doesn't show up very well, but it's green without a doubt. I remember I missed a nice piece from the same seller I bought this one from, it had several layer of different colors (milky white, Amethyst, reddish termination) with one being of a deep "John Deer" green color.

Amethyst from France's Auvergne shows some color-banding with sometimes a green layer.]]> Aymeric Longi Rockhounds Mon, 05 May 2008 21:47:57 +0000 http://www.mindat.org/forum.php?read,15,38542,96712#msg-96712 http://www.mindat.org/forum.php?read,15,38542,96712#msg-96712 Thanks
Faukh
(+91-9461276169 )]]> Farukh Rockhounds Mon, 05 May 2008 09:29:58 +0000 http://www.mindat.org/forum.php?read,15,38542,93051#msg-93051 http://www.mindat.org/forum.php?read,15,38542,93051#msg-93051 Rock]]> Rock Currier Rockhounds Wed, 02 Apr 2008 12:30:24 +0000 http://www.mindat.org/forum.php?read,15,38542,92914#msg-92914 http://www.mindat.org/forum.php?read,15,38542,92914#msg-92914
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]]> Pimmy Rockhounds Tue, 01 Apr 2008 14:39:07 +0000 http://www.mindat.org/forum.php?read,15,38542,92546#msg-92546 http://www.mindat.org/forum.php?read,15,38542,92546#msg-92546
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.]]> SilicaKitty Rockhounds Sat, 29 Mar 2008 13:40:23 +0000 http://www.mindat.org/forum.php?read,15,38542,92476#msg-92476 http://www.mindat.org/forum.php?read,15,38542,92476#msg-92476 David Walker Barker Rockhounds Fri, 28 Mar 2008 19:53:11 +0000 http://www.mindat.org/forum.php?read,15,38542,89675#msg-89675 http://www.mindat.org/forum.php?read,15,38542,89675#msg-89675 Byron Rockhounds Tue, 04 Mar 2008 07:27:59 +0000 http://www.mindat.org/forum.php?read,15,38542,86051#msg-86051 http://www.mindat.org/forum.php?read,15,38542,86051#msg-86051
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.]]> Lawrie Berthelsen Rockhounds Tue, 22 Jan 2008 03:36:41 +0000 http://www.mindat.org/forum.php?read,15,38542,86050#msg-86050 http://www.mindat.org/forum.php?read,15,38542,86050#msg-86050 Mark Mauthner Rockhounds Tue, 22 Jan 2008 03:01:10 +0000 http://www.mindat.org/forum.php?read,15,38542,86045#msg-86045 http://www.mindat.org/forum.php?read,15,38542,86045#msg-86045 amethystguy Rockhounds Tue, 22 Jan 2008 01:58:28 +0000 http://www.mindat.org/forum.php?read,15,38542,82909#msg-82909 http://www.mindat.org/forum.php?read,15,38542,82909#msg-82909 Ray Ladbury Rockhounds Tue, 18 Dec 2007 15:44:59 +0000 http://www.mindat.org/forum.php?read,15,38542,82904#msg-82904 http://www.mindat.org/forum.php?read,15,38542,82904#msg-82904 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.]]> David Von Bargen Rockhounds Tue, 18 Dec 2007 14:27:33 +0000 http://www.mindat.org/forum.php?read,15,38542,82892#msg-82892 http://www.mindat.org/forum.php?read,15,38542,82892#msg-82892
Jolyon]]> Jolyon Ralph Rockhounds Tue, 18 Dec 2007 12:07:15 +0000 http://www.mindat.org/forum.php?read,15,38542,82889#msg-82889 http://www.mindat.org/forum.php?read,15,38542,82889#msg-82889
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.]]> Spencer I. Mather Rockhounds Tue, 18 Dec 2007 10:59:24 +0000 http://www.mindat.org/forum.php?read,15,38542,82885#msg-82885 http://www.mindat.org/forum.php?read,15,38542,82885#msg-82885
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]]> Bill Baker Barr Rockhounds Tue, 18 Dec 2007 09:13:22 +0000 http://www.mindat.org/forum.php?read,15,38542,82834#msg-82834 http://www.mindat.org/forum.php?read,15,38542,82834#msg-82834
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 Jokela Jr Rockhounds Mon, 17 Dec 2007 17:15:21 +0000 http://www.mindat.org/forum.php?read,15,38542,82808#msg-82808 http://www.mindat.org/forum.php?read,15,38542,82808#msg-82808
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]]> Jolyon Ralph Rockhounds Mon, 17 Dec 2007 11:12:44 +0000 http://www.mindat.org/forum.php?read,15,38542,80239#msg-80239 http://www.mindat.org/forum.php?read,15,38542,80239#msg-80239
? 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]]> marc james Rockhounds Sat, 17 Nov 2007 04:19:28 +0000 http://www.mindat.org/forum.php?read,15,38542,75097#msg-75097 http://www.mindat.org/forum.php?read,15,38542,75097#msg-75097 loverocks Rockhounds Tue, 11 Sep 2007 11:10:11 +0000 http://www.mindat.org/forum.php?read,15,38542,67332#msg-67332 http://www.mindat.org/forum.php?read,15,38542,67332#msg-67332
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.]]> Tinno Alba Rockhounds Wed, 13 Jun 2007 03:16:26 +0000 http://www.mindat.org/forum.php?read,15,38542,50750#msg-50750 http://www.mindat.org/forum.php?read,15,38542,50750#msg-50750
:~}]]> Alan Plante Rockhounds Wed, 15 Nov 2006 04:57:05 +0000 http://www.mindat.org/forum.php?read,15,38542,50684#msg-50684 http://www.mindat.org/forum.php?read,15,38542,50684#msg-50684 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???]]> Jenny Rockhounds Tue, 14 Nov 2006 14:04:43 +0000 http://www.mindat.org/forum.php?read,15,38542,47904#msg-47904 http://www.mindat.org/forum.php?read,15,38542,47904#msg-47904
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]]> Alan Plante Rockhounds Sun, 08 Oct 2006 14:30:41 +0000 http://www.mindat.org/forum.php?read,15,38542,47892#msg-47892 http://www.mindat.org/forum.php?read,15,38542,47892#msg-47892 I am Nazmi Raheem from Sri lanka. I need some information about Malawi gem stones and mining placess in Malawi.Thank You.]]> Nazmi Raheem Rockhounds Sun, 08 Oct 2006 06:57:49 +0000 http://www.mindat.org/forum.php?read,15,38542,47718#msg-47718 http://www.mindat.org/forum.php?read,15,38542,47718#msg-47718
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.]]> Peter Nancarrow Rockhounds Wed, 04 Oct 2006 10:31:35 +0000 http://www.mindat.org/forum.php?read,15,38542,47713#msg-47713 http://www.mindat.org/forum.php?read,15,38542,47713#msg-47713 Aymeric Longi Rockhounds Wed, 04 Oct 2006 08:28:33 +0000