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 Post subject: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Mon Jan 10, 2011 5:06 am 
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As you might know first these amazing high luster Red-Orange sapphires come to market of Chanthaburi,Thailand, in 2001 which has been new development of Heated treatment with beryllium and unlike Surface Bulk Diffusion the color is not just on the surface of the stone. and diffusion is done to the core, So if something happens and a re-cut is needed stone shouldn't loose the color. these sapphire calls different names like: Sunset Sapphire, Red Orange sapphire, Sun Sapphire, Imperial Sapphire and Cinnamon Sapphire and the traders in Chanthaburi have call these Songea Sapphire and sometimes Songea Ruby because of its origin. as to my understanding these stones are from Sapphire variety not Ruby, but i have seen some AIGS Lab Reports for rubies which in comments it has been noted that its been treated with Light Element and it has very nice orangish-red color so why AIGS classified it as Ruby and not Sapphire?
Songea sapphires can't be called ruby because the color is not from Chromium, but from Beryllium.

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Mon Jan 10, 2011 7:05 am 
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i got a nice reply from AIGS:

Quote:
Dear Farshid,

As you know the distinction between a ruby and sapphire can be debatable. For example, at what point do you call a pink sapphire, a sapphire, and at what point it does it become a ruby? Sometimes, it depends on whether you are a buyer or a seller.

Up until now, there is no standardised colour grading environment and nomenclature for colour in ruby/sapphire in the industry. In AIGS, the identification of ruby/sapphire is based on the colour appearance matched to our colour sample set. Based on AIGS' years of experience, when there is enough saturation of the red hue present in the corundum, we would call it a ruby, likewise for yellow/orange/blue sapphire, so on and so forth. The identification is based on the colour of the corundum.

We thank you for your kind advice and comments.


and my reply:

Quote:
....in my humble opinion the cause of color is also important, if the color is result of Chromium then it's Ruby but if its because of Beryllium then it is Sapphire but again i heard from other gemologist that cause of color of The Red/Pink Corundum from Songea is Chromium but brown/purple is Beryllium. but in Songea Ruby case a ruby with that color would give a very strong reaction because they would be loaded with Chromium and very little Iron so if we call it ruby it shouldn't have lack of Chrome lines in the refractometer absorption in red......


this is kind of twisted for me too :roll:

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Mon Jan 10, 2011 8:28 am 
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Unified AGTA / GIA / Gübelin / SSEF disclosure policy: http://www.ssef.ch/en/news/news13.html
as you see its clearly pointed out sapphire also about the treatment The surface related layer.
can be a shallow layer or may also extend to a greater depth (up to the core).

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Wed Jan 12, 2011 2:41 am 
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Interesting :D Thanks

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Wed Jan 12, 2011 4:45 am 
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well i don't know how other gemologists here think and unfortunately no one replied.
but i think naming based on enough saturation of the red hue present in the corundum is not according to what i have learned in GIA.

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Wed Jan 12, 2011 7:12 am 
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Well, I don't know what the GIA course notes say, but the whole issue of naming gem corundums has been an ongoing debate for decades. Mostly it has centered on the question whether there is pink sapphire at all, or only rubies, but later on there has been some discussion regarding Be coloured stones as well, which is probably why you haven't got any answers so far, because there isn't an established consensus about it.

Traditionally in the west, any bright red gem has been called ruby. During the last few centuries it has come to mean red gem corundum only. Later on, the past hundred years or so, gemmological sciences developed and we could determine with certainty what which is corundum and what which is not, and also came to understand that the natural colouring agent in rubies were Cr3+, with or without a modifying iron content. Pink stones were rarily seen in the west since they were rejected as less than satisfying rubies. This changed when the trade began to market them as pink sapphires with merits of their own rather than as poor rubies. After some initial resistance, they became more or less recognized as such and people in the know, labs and amateur gemmologists alike began to do an arbitrarily made division between rubies and pink sapphires, some defined more than 50% tone as rubies, some defined less than 30% tone as sapphires etc. And that's where we are left today. Plus that we have got this issue of Be coloured stones that adds a new headache.

The Eastern tradition isn't my forte, but as I gather it, in India and much of the far east, any reddish corundums whether deep red or light pink have always been considered rubies, until recently. Then the aforementioned marketing strategy spread, and I don't know how widespread it is in use over there nowadays, but I suspect a lot of people still consider it a foreign idea and still calls any red corundum ruby, regardless of colouring agent or depth of colour.

However, we can conclude that traditionally, the only real definition of ruby is that it should be a corundum and it should be red. But until recently, the only way for a corundum to be really red was to be coloured by chromium. So rubies are red corundums, and they are red in nature because of chromium, but does that mean that rubies must contain chromium? That's the question. Some say yes, some say nay.

We know what the trade says, but what say you?
This could be a good discussion, thanks for lifting it, Roshanravan!

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Wed Jan 12, 2011 7:37 am 
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when its red i call it ruby
when its red because of added chemicals i call it "treated ruby" + details about the treatment in comments

:D

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Wed Jan 12, 2011 8:08 am 
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Jung Kee wrote:
.....
This could be a good discussion, thanks for lifting it, Roshanravan!

thank you Jung Kee for useful information and what you said explained more. i heard some lab doesn't simply give reports for Be treated Sapphires/Rubies because of this Naming also the Be Enhancement is not explained in AGTA as any enhancement definition but AGTA & GIA & Gübelin & SSEF came to an agreement to use "confined to a surface related layer." for Comment section but other labs use "Heat enhancement with light elements was applied" or "H(Be) Enhanced by heat and light elements (e.g. Beryllium)." anyway i haven't seen any GIA report for one of these Be Treated Sapphires/Rubies

i guess naming for color agent is more correct than percentage of Red Hue and Saturation!

studiogem wrote:
when its red i call it ruby
when its red because of added chemicals i call it "treated ruby" + details about the treatment in comments
:D

that is not a gemological point of view and unfortunately there is no clear disclosure from CIBJO.

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Wed Jan 12, 2011 8:09 am 
roshanravan wrote:
well i don't know how other gemologists here think and unfortunately no one replied.
but i think naming based on enough saturation of the red hue present in the corundum is not according to what i have learned in GIA.


Well, I don't learn from GIA but I agree with you that basing gem variety identification on colour shade seems like building on a shaky foundation. What if we did that for all gemstones?

It seems clear that there is tension between the requirements of mineralogy and the jewellery trade. The former requires identification and labelling on a rational, if sometimes arbitrary, basis according chemical composition and, sometimes, physical structure. The second requires trade-friendly descriptions and lore that promote either or both of sales volume and unit sales margins. Gemmology, which is scientifically based, sits uncomfortably somewhere between. If it's roots are in science, it owes its existence to the jewelery trade, without which it almost certainly would cease to exist and become simply one field of study within the larger canon of minerological knowledge.

I watch and learn about this dichotomy with interest. My guess is that the rift between the science of mineralogy and needs of the jewellery trade is likely to grow wider rather than to diminish. To where this is going to lead eventually seems not at all clear to me at present.

I have just received two little stones bought as sapphires. One is blue, comes from Sri Lanka and is entirely inert to UV. The other is a brilliant pink and comes from Vietnam and looks like a hot coal under UV LW. There is no prize for guessing which fluoresces strongly at about 690 nm under the spectroscope :D *Not* the typical Chromium doublet though but a narrow band of fluorescence just a little wider, overall, then a Chromium doublet would be. I think (wish my eyes still had the acuity of youth) that the fluorescent band is not uniform but comprises a series of bright red lines so closely spaced that my eyes cannot discriminate between them with certainty. Any thoughts as to what might be the cause of such a narrow band red fluorescence?


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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Wed Jan 12, 2011 8:57 am 
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Kerensky wrote:
Well, I don't learn from GIA but I agree with you that basing gem variety identification on colour shade seems like building on a shaky foundation. What if we did that for all gemstones?


Actually, that is exactly what which is happening with a lot of gemstones. Just look at the garnet group mess. There is some chemical distinctions between them, but the dividing lines are VERY arbitrary and isn't followed very much. Which is why this discussion is interesting and needed. I don't suppose that we'll ever solve the problem, it do be an inherent conflict of interests in it as you so aptly pointed out, but by discussing it we can get closer to get a working consensus, however arbitrary the individual decisions.

I think that it do be right to determine the gem mineral in a scientific way, that is to say determine it by classification due to chemical or physical properties, however gem variety isn't really a question of what a stone is, but what it is perceived to be. When you think about it, most of the gem variety names don't denote a particular kind of stone foremost, but a particular colour. Say sapphire to an average member of the general public not involved in the gem trade, and that person will most likely think of "blue" firstly, in the same way you would think of red when hearing "ruby". Thus, perception and impression is more important than science when it comes to determine gem variety.

To illustrate this, just think of Tsavorite vs Mint garnets, both of them are green grossulars, or even calcium-aluminium silicates if you want to be more scientific, coloured by either vanadium and/or chromium, but they aren't of the same gem variety. In this example, you must in fact determine it by doing an arbitrary judgement of the colour, since even if you did a scientific analysis of the exact content of colouring agents , you still wouldn't be sure of what it looked like without actually looking.

Therefore I'm thinking that AIGS is right in judging a red corundum a ruby, regardless of colouring agent, but also that it makes it all the more important that we see a greater penetration of disclosure within the trade. Because in the same way that gemmolgy has been developed from the needs of the trade, the trade must heed the gemmological findings to actually get any benefits from it.

That's what I think though, others may and will probably disagree.

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Wed Jan 12, 2011 4:44 pm 
Jung Kee wrote:
Kerensky wrote:
Well, I don't learn from GIA but I agree with you that basing gem variety identification on colour shade seems like building on a shaky foundation. What if we did that for all gemstones?


Actually, that is exactly what which is happening with a lot of gemstones. Just look at the garnet group mess. There is some chemical distinctions between them, but the dividing lines are VERY arbitrary and isn't followed very much. Which is why this discussion is interesting and needed. I don't suppose that we'll ever solve the problem, it do be an inherent conflict of interests in it as you so aptly pointed out, but by discussing it we can get closer to get a working consensus, however arbitrary the individual decisions.


I've just about got my head around the mess of garnet substitutions and gemmological classification. I agree that the varietal name 'Rhodolite' serves a useful purpose (largely because of the colour, so easily recalled from memory). This is an actual aid to identification of this nature's muddle between Almandine and Pyrope.

So yes, I give ground and agree that colour has a useful place in the derivation of varietal names, falling back to the line that most other most cases where the colour in not inherent in the name (such as in Rhodolite) the colour should be a modifying descriptor to the species (e.g. White Pectolite or Blue Microcline). Whether such a compound name should warrant Variety status perhaps depends on the cause of the colouration and the uniformity of its occurrence? In other words, if a defining colouration can arise from more more than one cause, of if the colour is not defining, then the use of colour to categorise Variety risks confusion, more perhaps than it provided clarification?

So what should we call my pretty, vibrant pink and brilliant Vietnamese stone? Perhaps I should first check its RI, biref and SG before pushing this further :wink:

Quote:
....... just think of Tsavorite vs Mint garnets, both of them are green grossulars, or even calcium-aluminium silicates if you want to be more scientific, coloured by either vanadium and/or chromium, but they aren't of the same gem variety. In this example, you must in fact determine it by doing an arbitrary judgement of the colour, since even if you did a scientific analysis of the exact content of colouring agents , you wouldn't still be sure of what it looked like without actually looking.


So how does labelling a green garnet 'Mint' help distinguishh between the two stones? Are we making the same point?

Quote:
In the same way I'm thinking that AIGS is right in judging a red corundum a ruby, regardless of colouring agent, but that it makes it all the more important that we see a greater penetration of disclosure within the trade. Because in the same way that gemmolgy has been developed from the needs of the trade, the trade must heed the gemmological findings to actually get any benefits from it.


So should we call my hot pink Sapphire a Ruby? There's certainly more red in there than any other colour, with a hind of purple (which one can sometimes see - but much stronger - also in some Ruby ? As already noted, what is causing it to fluoresce like a Ruby would seem to be more than just Chromium traces.

Quote:
That's what I think though, others may and will probably disagree.


I think this may be another one of those discussions in which agreement/disagreement is not the real point of the discussion, nor necessarily its most useful outcome in the short term


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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Wed Jan 12, 2011 5:13 pm 
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Kerensky wrote:
So yes, I give ground and agree that colour has a useful place in the derivation of varietal names, falling back to the line that most other most cases where the colour in not inherent in the name (such as in Rhodolite) the colour should be a modifying descriptor to the species (e.g. White Pectolite or Blue Microcline). Whether such a compound name should warrant Variety status perhaps depends on the cause of the colouration and the uniformity of its occurrence? In other words, if a defining colouration can arise from more more than one cause, of if the colour is not defining, then the use of colour to categorise Variety risks confusion, more perhaps than it provided clarification?


Well, shouldn't you call ruby and sapphire red and blue corundum then? To eliminate as much confusion as possible, we should just stick with the mineral names, or even the chemical formulae, but I can't see that happening. Naming is part of language, and as with all languages, it is bound to be lots and lots of exceptions to the rules. And that might be confusing to the uninitiated, but to those who knows and agrees to it, it might be working very well.

Quote:

So how does labelling a green garnet 'Mint' help distinguishh between the two stones? Are we making the same point?


It doesn't, and that was the whole point of my post. It only helps us to distinguish between the perception of the colour in the same kind of stone. Which is what determines the variety in this case. The example might have been a poor choice, as GIA doesn't recognize Merelani Mint as a variety, but they recognize Tsavorite and for sure don't call every green grossular passing their labs for Tsavs. So the colour is still used to determine when it isn't Tsavorite anymore.

Quote:

So should we call my hot pink Sapphire a Ruby? There's certainly more red in there than any other colour, with a hind of purple (which one can sometimes see - but much stronger - also in some Ruby ? As already noted, what is causing it to fluoresce like a Ruby would seem to be more than just Chromium traces.


I wouldn't dream about answering that without seeing the stone in question! But if you show it to somebody on the street and ask if they think it is red, you might have an answer (just don't forget to check so that they aren't colour blind! ;)). I wouldn't call pink red though.

Quote:
I think this may be another one of those discussions in which agreement/disagreement is not the real point of the discussion, nor necessarily its most useful outcome in the short term


Agreed! :D

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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Thu Jan 13, 2011 11:49 am 
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Sidebar:
Dick Hughes article on Ruby.

and his article on naming gems:
The Name Game


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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Thu Jan 13, 2011 4:21 pm 
Barbra Voltaire wrote:
Sidebar:
Dick Hughes article on Ruby.

and his article on naming gems:
The Name Game


Thanks Barbra, 'The Name Game' is particularly timely.

Jung Kee:

[quote "Jung Kee"]
Well, shouldn't you call ruby and sapphire red and blue corundum then? To eliminate as much confusion as possible, we should just stick with the mineral names, or even the chemical formulae, but I can't see that happening. Naming is part of language, and as with all languages, it is bound to be lots and lots of exceptions to the rules. And that might be confusing to the uninitiated, but to those who knows and agrees to it, it might be working very well[/quote].

I can't see centuries of tradition being ditched nor any great advantage accruing if it were. However, even here the position seems not entirely satisfactory. It seems no longer sufficient to say that Ruby is red Corundum and and all other Corundum is Sapphire. What shall we do about pink Corundum? Or Songea Sapphire? More of this in a minute.

Quote:

So how does labelling a green garnet 'Mint' help distinguish between the two stones? Are we making the same point?

Quote:
It doesn't, and that was the whole point of my post. It only helps us to distinguish between the perception of the colour in the same kind of stone. Which is what determines the variety in this case. The example might have been a poor choice, as GIA doesn't recognize Merelani Mint as a variety, but they recognize Tsavorite and for sure don't call every green grossular passing their labs for Tsavs. So the colour is still used to determine when it isn't Tsavorite anymore.

How does 'Mint' help? Which 'mint'? From where and at which time of the year? This seems to be marketing, pure and simple. Is it a box of chocolates? *If* there is a case for making a varietal distinction between these two green Grossulars then why not Tsavorite and Merelanite? Or, instead of Merelanite, could one simply opt for 'pale Tsavorite'? Or perhaps even just 'Tsavorite', leaving to the salesman whatever modifying adjective as may be wished?
For reasons I can't quite fathom, 'Merelani Mint' sets my teeth on edge even more than does 'Larimar' :)

Quote:
So should we call my hot pink Sapphire Ruby instead? There's certainly more red in there than any other single colour, with a hind of purple (which one can alaso often see in some Ruby ? As already noted, what causes it to fluoresce like a Ruby would seem to be Chromium traces, possibly plus something else.

I spend some time last night with Webster, GT Pro and the OPL student's guide to spectra. All remark on the likely (but not certain) presence of the emission doublet in Rubies and pink Sapphire. AFAICS, none have a description of a single strong line/narrow band instead of the doublet. Eyes and spectroscope checked against a Ruby showing the 'standard' fine emission line doublet. Ah well..... as a wise friend once said to me, "With spectroscopy, what you see is what you get".

Quote:
......I wouldn't dream about answering that without seeing the stone in question!

Now you miss the point :D The question was not 'What is this stone?' But 'Has any one seen or heard of a pink Sapphire - or any other stone - in which the fine line emission doublet associated with Chromium, becomes one narrow band/strong line at the same spectral position?

Quote:
I wouldn't call pink red though.
[/quote]

Well what should pink be if not white lightly shaded with red? Pink is the colour you get if you add just a few drops of fresh blood to a small glass of clean water. How much red does one need before the variety swaps from Sapphire to Ruby? I have seen pink-ish stones on sale as Ruby and I bet you have too.
As, no doubt, we are going to continue with the use of both Ruby and Sapphire as the varieties of Corundum, perhaps it might be better to fix globally - and arbitrarily if needs be - some watershed division between the two rather than to let the matter slide?
It seems to me that nomenclature should be a bit like grammar. It should have some principles at its foundation and a structure that is to some extent predictable. (DH seems to thinks so too and with a far weightier opinion). Sure there are always going to 'irregular verbs' that don't follow the normal rules but these can coped with. But, give up all structure in naming and and you end in a marketeer's paradise. in which alliteration, pizz-azz and 'feel good' are all that is important in words and no one cares what the content actually is. When 'Merelani Mint' chocolates - or cosmetics - or garnets even - are put on the market, are they bought because of clearly differentiated content - or because of the glitzy launch advertising, with presentation and price both being refined for a targeted market sector?

If you think that such considerations should have nothing to with gemmology, I'd say you were right. However, unless a common grip is maintained on rules for gemmological nomenclature, I think that's the road we head down. Those who determine the use of the words win the argument.


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 Post subject: Re: Why AIGS refers Songea Sapphire as Ruby
PostPosted: Thu Jan 13, 2011 5:57 pm 
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Kerensky wrote:
I can't see centuries of tradition being ditched nor any great advantage accruing if it were. However, even here the position seems not entirely satisfactory. It seems no longer sufficient to say that Ruby is red Corundum and and all other Corundum is Sapphire. What shall we do about pink Corundum? Or Songea Sapphire? More of this in a minute.

Quote:

How does 'Mint' help? Which 'mint'? From where and at which time of the year? This seems to be marketing, pure and simple. Is it a box of chocolates? *If* there is a case for making a varietal distinction between these two green Grossulars then why not Tsavorite and Merelanite? Or, instead of Merelanite, could one simply opt for 'pale Tsavorite'? Or perhaps even just 'Tsavorite', leaving to the salesman whatever modifying adjective as may be wished?


I told you that the example was ill choosen! ;)
The point is that without marketing considerations, we wouldn't have any varietal names at all. Indicolite? Rubellite? Morganite? Heliodor? Kunzite? Hiddenite? All of it is marketing names that has become varietal names defining a perceived difference. There might be a scientific difference or not, but it doesn't matter, what matters is what people in general perceive and believe. You might dislike the "Mint" designation to garnets, but most people obviously do not, and sees a very real difference between Merelani Mints and Tsavorites. This is the razor edge gemmology needs to walk, to be able to be on the border between rational science and unrational reality.

Quote:
I spend some time last night with Webster, GT Pro and the OPL student's guide to spectra. All remark on the likely (but not certain) presence of the emission doublet in Rubies and pink Sapphire. AFAICS, none have a description of a single strong line/narrow band instead of the doublet. Eyes and spectroscope checked against a Ruby showing the 'standard' fine emission line doublet. Ah well..... as a wise friend once said to me, "With spectroscopy, what you see is what you get".

Now you miss the point :D The question was not 'What is this stone?' But 'Has any one seen or heard of a pink Sapphire - or any other stone - in which the fine line emission doublet associated with Chromium, becomes one narrow band/strong line at the same spectral position?


Nope, I'ven't, sorry! :^o
I think I've seen it in Vietnamese spinel though, I'll search for the stone and check it.

Quote:

Well what should pink be if not white lightly shaded with red? Pink is the colour you get if you add just a few drops of fresh blood to a small glass of clean water. How much red does one need before the variety swaps from Sapphire to Ruby? I have seen pink-ish stones on sale as Ruby and I bet you have too.

As, no doubt, we are going to continue with the use of both Ruby and Sapphire as the varieties of Corundum, perhaps it might be better to fix globally - and arbitrarily if needs be - some watershed division between the two rather than to let the matter slide?


It is true that scientifically pink is a pale red, but it is not what it is perceived anymore, yet again it isn't really a rational matter. In the olden days here in the West, a couple of hundred years back or so, there was no differentiation between red and pink, since everyone knew that pink was a poor red. And that was because red clothes after a couple of washes became pink, it is only with the invention of pure chemical dyes that we've got red cloth that stays red for a considerable time. Since then we've gotten stable colours and far more saturated colours than anyone could dream about in the middle ages. A consequence of that is that we have had a lot of previously rare or unimaginable shades of known colours emerge as new colours with an identity of their own. This is an ongoing process, take for example the recently minted "Paraiba" which is serving both as a description of origin, of a specific colour and of a specific look. Pink is another of those emergences and I don't think that there is a need for "fixing", nor can I see how you could do it practically. It will fix itself given time enough, as the marketplace recognize its occurence and establish its place into the whole of everything. It may sound lax, but it isn't, it is the flow of time that decide more often than not, rather than people like you and me inventing rules that nobody will follow.

Quote:
It seems to me that nomenclature should be a bit like grammar. It should have some principles at its foundation and a structure that is to some extent predictable. (DH seems to thinks so too and with a far weightier opinion). Sure there are always going to 'irregular verbs' that don't follow the normal rules but these can coped with. But, give up all structure in naming and and you end in a marketeer's paradise. in which alliteration, pizz-azz and 'feel good' are all that is important in words and no one cares what the content actually is. When 'Merelani Mint' chocolates - or cosmetics - or garnets even - are put on the market, are they bought because of clearly differentiated content - or because of the glitzy launch advertising, with presentation and price both being refined for a targeted market sector?

If you think that such considerations should have nothing to with gemmology, I'd say you were right. However, unless a common grip is maintained on rules for gemmological nomenclature, I think that's the road we head down. Those who determine the use of the words win the argument.


That do be the road we are heading down, and that's the road we've always been on. The trade do steer a lot of the course of things regarding gems and especially the naming of it, to think it is the other way around would be rather conceited i think. At the same time it can't do entirely as it pleases, as it would be bad for the trade if things got too messy or it lost trust among the public because of it's doings, so it is pretty much self regulatory. What gemmology can do is to think deep and present good possibilities and a rational mean, rather than trying to apply stiff rules where there could be none.

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