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Green amethyst vs. Oroverde quartz


#1

I have some rough “oroverde quartz,” sold to me originally as
"golden green citrine." Some of it is much more green than golden or
yellow. I put one crystal in a northern window and virtually all the
yellow faded.

I’m wondering what the difference might be between “oroverde” and
"green amethyst." It was my understanding that oroverde came from
Brazil and was irradiated with the same process as turns much topaz
blue.

On another note. We should try and squash this green amethyst name
as soon as possible. As others have mentioned this freewheeling
naming of existing material is nothing but deleterious to common
understanding.

Derek Levin
www.gemmaker.com


#2

It sounds like the variation on lemon quartz (lee-mohn quartz for
you QVC watchers) that is commonly called green-gold. It does vary
from nearly lemon to nearly lime. Not the same as green amethyst.

Brian Corll
Vassar Gems


#3
On another note. We should try and squash this green amethyst name
as soon as possible. As others have mentioned this freewheeling
naming of existing material is nothing but deleterious to common
understanding. 

I agree completely, which is why I will now refer to the stones I
got as prasiolite, even when buying more from the dealer who called
it “green amethyst” (maybe they’ll catch on that it’s an issue if
everyone does this over time).

Karen Goeller


#4
I'm wondering what the difference might be between "oroverde" and
"green amethyst." It was my understanding that oroverde came from
Brazil and was irradiated with the same process as turns much topaz
blue. 

The correct spelling is two separate words: ouro verde (literally,
green gold). Ouro Verde is a municipality in Brazil where ouro verde
quartz is mined. Green “amethyst,” or prasiolite, is heated
amethyst. Ouro verde quartz is sold as just that, nobody (to my
knowledge) calls it green gold “amethyst,” but I’m sure it would
become very popular and make everyone a lot of money if we did.
Please don’t. If you do, I’ll petition all gemologist appraisers to
raise their rates to compensate for the extra work.

James S. Duncan, G.G.
James in SoFL


#5

Karen et al,

I agree that the term “green amethyst” should not be used. I’m
having trouble figuring out how “celery green” has no yellow, but
I’d suggest just using the clearest language possible: green quartz,
yellow-green quartz, etc.

BTW there is a beautiful green synthetic quartz available, much more
saturated than most of the natural material.

Wayne Emery
The Gemcutter


#6

Hi folks,

I’m probably poking the hornets nest, but sometimes you just have
to.

What is really wrong with saying “green amethyst”? It doesn’t seem
like a misnomer really (it is amethyst that has been heat changed by
man or mother nature), and not "deleterious to common understanding"
as another poster so succinctly put it. And it certainly sounds
better than green quartz (esp. when people assume ‘quartz’ is glass
these days) and what average consumer is going to buy something they
don’t know how to pronounce (prasiolite)? I don’t think I would have
back before I got interested in minerals.

Oh, I know the purists are going to freak out over anything slightly
off center, and they’d probably prefer it if everyone called stones
by their chemical comp. names rather than common names. But Jane
Public or John Doe isn’t going to care about that. This issue
wouldn’t seem like a real issue, not like the smokey quartz vs.
smokey topaz issue, or other hugely misleading names.

I’ve never actually seen “green amethyst”, but I think I might like
to.

Dawn B. in central Texas…tomato plants took a beating in last
night’s thunderstorms and the stroller tires picked up 8 lbs of mud
on our daily walk this morning.


#7

But in some cases the stones are “green amethyst” (albeit made
green by radiation) as opposed to prasiolite or green-gold quartz. I
don’t think most people are intentionally causing confusion. We have
too many danged different kinds of gems to separate out. Naming
conventions differ from country to country, and some foreign dealers
aren’t sure what to call something in English.

Brian Corll
Vassar Gems


#8
I'm wondering what the difference might be >between "oroverde" and
"green amethyst." 

Ouro Verde…Oroverde… or Green Gold Quartz is made by irradiating
clear quartz with Cobalt 60 Gamma Ray irradiation.

On another note. We should try and squash this green >amethyst
name as soon as possible. 

The “Green Amethyst” is Prasiolite or Vermarine when it is natural.

The correct name for the Amethyst material that is heated and turns
light green is “Greened Amethyst”. The name has deteriorated to
"Green Amethyst" The correct term should be “Greened Amethyst”.

See the references below.

  bernieslapidary.com/selprod.asp?CAT=GEM&OTHER=YES
     Prasiolite or Vermarine Also known as Greened Amethyst
     produced by careful heating of Amethyst from one Brazilian
     location from the deposit Montezuma in Minas... 

  http://www.tradeshop.com/gems/quartz.html 
     QuartzVermarine, also known as Prasiolite or "Greened"
     Amethyst is a light to medium green quartz produced by
     careful heating of amethyst from one Brazilian... 

Best Regards,
Robert P. Lowe Jr.
Lowe Associates - Brasil
Gemstones, Rough, Specimens


#9

I’m just back from Brazil, where I had a chance to talk to the
company that’s doing the treatments on both the “green amethyst”
(also called prasiolite) and the “Oro Verde” quartz. Both stones
were originally colorless quartz that was irradiated; the “green
amethyst” is from a single mining area in the south of Brazil, where
the quartz contains iron impurities that cause it to turn that
particular color with radiation. “Oro Verde” is from other areas.

Morgan Beard
Colored Stone
www.colored-stone.com


#10

When I was in Tucson this year, it seemed that the green amethyst
was everywhere, but so was a pale purple that they called pink
amethyst. Is the “pink amethyst” equally as misleading as the green
amethyst?

Linda


#11

The “pink amethyst” was probably Rose de France amethyst.

Brian Corll
Vassar Gems


#12
What is really wrong with saying "green amethyst"? It doesn't seem
like a misnomer really 

Amethyst is purple, not green. Any other color of quartz is not
amethyst. If yellow, it’s citrine. To illustrate, please consider
these varieties of beryl: goshenite isn’t referred to as white
"emerald," or morganite as pink “emerald,” or aquamarine as blue
"emerald," we should not refer to prasiolite as green “amethyst.” It
really is a misnomer.

(it is amethyst that has been heat changed by man or mother
nature), and not "deleterious to common understanding" 

As you said, it has been changed. It has been changed from amethyst
to prasiolite. If it has been changed from amethyst to prasiolite,
referring to it as amethyst is most certainly “deleterious to common
understanding.”

And it certainly sounds better than green quartz (esp. when people
assume 'quartz' is glass these days) and what average consumer is
going to buy something they don't know how to pronounce
(prasiolite)? I don't think I would have back before I got
interested in minerals. 

This is, of course, why people are calling prasiolite by this name,
so they can sell more of it by increasing desire via using a more
widely known variety of quartz. Sure, you’ll sell more in the short
term, but when people find out that it isn’t really amethyst, they
will feel ripped off and will hesitate to purchase gems and jewelry
from the industry who told them their green quartz is amethyst.

Oh, I know the purists are going to freak out over anything
slightly off center, and they'd probably prefer it if everyone
called stones by their chemical comp. names rather than common
names. But Jane Public or John Doe isn't going to care about that..

This isn’t about purism, it’s about not intentionally misleading the
public about what we’re selling them. Jane Public would be
absolutely livid if she found out that the green “ruby” she bought
was really only a cheap, $20/ct sapphire. Just as a ruby must be red,
an emerald must be green, an amethyst must be purple. When
translucent zoisite is a dreary brownish color, it’s just brown
zoisite. When enhanced to violetish blue or purple, it is Tanzanite.
If dealers referred to the natural crystal as brown “tanzanite” and
told the public that “it is great for opening the spleen chakra and
vibrates to the number eleventy-one” it would probably sell like
hotcakes. And that’s what it is all about. Few jewelry store
customers will buy pale green prasiolite, but plenty of folks will
consider green “amethyst.” Just remember that every time a retailer
sells it under this name, eventually most of them will find out that
it isn’t amethyst at all.

This issue wouldn't seem like a real issue, not like the smokey
quartz vs. smokey topaz issue, or other hugely misleading names 

As a gemologist who does appraisals for the public and various
organizations, I know that referring to prasiolite as green
"amethyst" on an official document would be not only incorrect, but
completely unprofessional and absolutely irresponsible. Selling it
under that name would be just as incorrect. Use all the misnomers you
want, but don’t complain when you’ve lost your customer’s confidence
by selling them something that isn’t what you told them it was. Maybe
that issue would be real enough for everyone.

James S. Duncan, G.G.
James in SoFL


#13

I am inclined to doubt the categorical assertion that “green
amethyst” is originally clear quartz. At Tucson in 2005 I encountered
a greenish-yellow irradiated quartz which was originally clear
quartz, but which was at the time being marketed as “lemon quartz”.
Perhaps today it is being called green amethyst. Two years ago it was
not. Perhaps everything that is being marketed as "green amethyst"
today is irradiated quartz which was orginally clear. It may be so. I
do not know. If it is indeed so the material deserves its name even
less.

But it seems unlikely. For in fact “green amethyst” has been around
for just over half a century, long before radiation treatments became
common. And when it first came onto the market it was exactly that:
not clear quartz but rather amethyst which had been turned green by
heat treatment. And it did all come from one single mine.

I have before me a 50 year old publication by Frederick L Pough
entitled “Greened Amethyst - an old friend in new attire.” In this,
Pough locates that mine as situated in Montezuma, about 37 miles
from Rio Pardo in the state of Minas Gerais; and reports that
amethyst is not usually (or was not usually then) mined in this
district. This is his account of the discovery:

  " A prospector working around the deposit placed a few of the
  old rejected amethystine masses together to make a fireplace
  over which he warmed his lunch on a fire built from a few twigs
  he had gathered....After he was finished, as the fire died out,
  he kicked his rock pile apart, and to his surprise found that
  the once amethystine stones had turned green." 

Pough goes on to state that the greening, after experimentation, was
achieved by a carefully controlled heat treatment, in contrast to
the throw-it-in-a-barrel arbitraryness of the treatment to get
citrine; that the market was baffled by this new color; that the
meaningless Portuguese word “prasiolite” which was coined for it did
not gain commercial acceptance; nor did the term “green quartz” suit,
for the Chinese were at the time widely selling carved vases and lamp
bases in green fluorite, which were apparently marketed as green
quartz. giving that designation, correct thought it was, prejudicial
connotations of soft stone.

So not only has the “green amethyst” been around for fifty years;
the quest for a suitable term for it has been also.

Cheers,
Hans Durstling
Moncton, Canada


#14
what average consumer is going to buy something they don't know
how to pronounce (prasiolite)? 

Actually, there is a significant portion of the buying public (at
least at the shows I do) who like having a little bit of arcane
knowledge to go with their purchase. They can get amethyst anywhere.
But if you explain “This is prasiolite, a green variety of quartz.
It is sometimes called green ametyst because…” then they can show
off their art fair ring and tell a little story about it. This can
add significantly to its appeal. FWIW, men seem to like this kind of
detail more than women do, especially if there is technology
involved, but I frequently have people of either persuasion come
back to my booth to tell friends the “stories” I explain to them
about my work (usually, how I create those little pictures in the
titanium, but you get the idea).

I will also add that, since this stuff was originally amethyst, the
new name doesn’t bother nearly as much as most of the others… like
"white turquoise". I had a student who would simply not accept the
idea that “white turquoise” is a contradiction in terms, a marketing
ploy, like saying “yellow ruby” or “purple emerald”.

Noel


#15

Dawn.

Well you are opening up a hornet’s nest but with good reason. I’m
sorry but there is not a gemological tract in the world that
describes amethyst as anything but purple. Amethyst is the purple
variety of quartz. Citrine is the yellow variety of quartz. You can’t
just decide that because John or Jane Doe won’t know the difference
that you can rename things as you see fit. And just because John or
Jane Doe public may be stupid enough to not know the difference is
not an excuse to continue to miseducate them. Additionally you are
dealing with an ethical dilemma here. If you don’t tell the customers
the truth about what this material is where do you draw the line?
I’ve already spent so much of my life cleaning up the misstatements,
misrepresentations and downright stupidity about diamonds and colored
stones (all told people by other “jewelers”) that I don’t want to do
it anymore. Come stand in my shoes for a few years and then tell me
it’s ok to name anything whatever you want.

Daniel R. Spirer, G.G.
Daniel R. Spirer Jewelers, LLC
1780 Massachusetts Ave.
Cambridge, MA 02140
617-234-4392
@Daniel_R_Spirer
www.spirerjewelers.com


#16

James,

Absolutely spot on.

The original post saying “people assume ‘quartz’ is glass these
days” says it all.

The plethora of ‘fruit’ quartz last year which was exposed as being
glass (or at best fused quartz) has devalued all quartz in the public
imagination.

Pat Waddington
www.pajed.co.uk
www.metalclayuk.co.uk


#17

Hans,

Pough’s recitation is correct. An old issue of Gems & Gemology from
the mid-80’s, as I recall, gave the same along with a
photograph of the heated green material from Montezuma. As far as I
know, this is the only area that produces such material (amethyst
that turns green when heated). All of the specimens I have seen in
the last 35 years or so have ben a fairly intense green, albeit with
a gray overtone, but attractive. In my experience, this material has
always been referred to as “greened amethyst”, a descriptively
accurate name. Some Brazilian quartz can be irradiated and
subsequently heat treated to various shades of yellowish-green to
greenish-yellow. This has been called Prasiolite and also Ouro Verde
quartz by rockhounds and some lapidaries. Neither term is an
officially recognized mineral name, and, as such, these terms tend
to get applied whenever it seems convenient or advantageous to the
sellers.

In addition, some quartz from Arkansas can be irradiated and heat
treated to a medium-light olive green which is quite attractive when
cut. I do not believe this is being done today, but was done by Mark
Liccinni and Tom Terwilliger years ago, before Mark’s passing. I
have some of this material uncut and have access to the old single
stash, and if anyone is interested I can supply some of this
material inexpensively. I’m not trying to sell anything here,
really, just letting folks know that the material is available.
Probably just an interesting historical footnote concerning Arkansas
material. It s quite a bit darker than the lemony green material so
prevalent these days from Brazil.

And, of course, there is a doped synthetic quartz being produced in
quantity by the Russians, available to cutters everywhere. It is a
strong green, unlike any of these other materials, and it, too, is
inexpensive and cuts interesting stones. They also produce a range
of blue quartzes as well as citrine, amethyst and ametrine. Like all
quartz, when faceted with the table perpendicular to the C axis of
the crystal, the stones are surprisingly brilliant, if a proper
polish is accomplished. Most folks have never seen one cut that way
(few bother or know how to locate that axis), but they can be real
blazers.

Wayne Emery
The Gemcutter


#18

Hi folks,

I have indeed poked the hornets nest, which can be quite fun.

Reponses have been wonderfully informative and civil (mostly), and I
thank everyone for that. I’ve learned a lot about what people think,
and the real reasons ‘why’ nicknames for gemstones shouldn’t be
encouraged.

BTW, I have always strived for truthfulness in my work.

Dawn B. in Taylor, Tx


#19

Why the naming is so important and the confusion so obvious. When I
originally bought my rough material, it was sold to me as lemon/lime
citrine. Later I was told is was golden green citrine. As I showed
it to more people in a wider area, I was told is was oroverde
quartz. So I changed to that as a name more standardized. I’m not
sure who first used this name or where, but obviously we went from
citrine to quartz as well as changing the first part of the name. I
switched to the Spanish because It sounded more exotic and seemed to
be what was going as a standard. But I used the Spanish language
spelling of gold green.

On this list I was corrected to ouro verde, which I’m guessing is
the Portuguese spelling. Haven’t looked that up. Since the material
capable of being changed by radiation to this color is reputed to
come only from Brazil, it would make sense to use the Portuguese
spelling. But in the course of about 8 years, I’ve been told 4
different names. Perhaps by the time the stuff is played out, we
will have agreed upon a name. But this has left me less than
enthusiastic about casual naming of gem materials. I just want to
cut and sell the stuff deciding between all the variations makes it
harder to price and harder to sell.

Then added into that issue is the question of radiation. I’ve been
told that in the case of both this material and blue topaz, the
radiation used is similar to the standard x-ray. Yet the idea of
"irradiation" frightens people.

Several years ago I met a man who worked in the defense industry
starting just after WWII and through the 60s. He worked on nuclear
reactors for enriching Uranium He told me and I have no independent
confirmation of this that as a sideline many people working there
also worked with diamonds for gemstone. As I recall, the process he
outlined would take brown diamonds and heat them to take them from
brown to white. Then they would put them into the reaction process
which would turn them blue and sometime other colors. I wonder how
widely known this practice is, if it’s still in use and, if it’s
true whether it has ever affected the diamond market. Anyone know of
this practice?

Derek Levin
www.gemmaker.com


#20
brown to white. Then they would put them into the reaction process
which would turn them blue and sometime other colors. I wonder how
widely known this practice is, if it's still in use and, if it's
true whether it has ever affected the diamond market. Anyone know
of this practice? 

The process you described is referred to in GIA’s courses, so I
always thought it to be widely known in the trade. At the gem and
jewelry shows I’ve visited for the past several years there have been
plenty of irradiated blue and green diamonds for sale. Most are
under.50ct and are I1 clarity or worse. I always pick up a few (you
should see the looks I get when I test the stones at the booth with a
geiger counter), and make a couple pairs of post earrings and
solitaire rings. They all sell within a couple of weeks.

The purpose of the geiger counter is to make sure there is no
residual radiation. I’m sure the man referred to in the original post
was required to store any stones that had unsafe radiation levels
until their half-life had decayed to safe levels (at least, that is
what is taught at GIA), but I’m not sure the home countries of the
dealers I see with these stones are under the same constraints. At
any rate, I have never come across any that set the counter off.

James S. Duncan, G.G.
James in SoFL