Pink rubies?

[Sagebrush]

I see the ruby/pink sapphire debate still rages on. I suggest taking a look at Richard Wise's new book: Secrets Of The Gem Trade, The Connoisseur's Guide To Precious Gemstones. An excellent chapter on ruby/pink sapphire. Some great photos including the famous Caplan Ruby that brought the highest per carat price ever, at auction. A definately pinkish gem! Even defines pidgeon blood!

New wrinkle, free worldwide shipping direct from the publisher:

www.secretsofthegemtrade.com

 

[mogok]

Hello,

I'm very new in this forum and this is my firts post.
I will try to help you on this controversial subject:

Corundum is Aluminium oxide. As a pure perfect crystal it is a colorless gemstone.
Now if some other elements or defects are present in the crystal they may have interaction with the light and create color.
Rubies and Pink sapphires own their color to the subsitution by Chromium of some Aluminium atoms within the crystal structure.
If only chromium is present the stone hue will be pure red
The stone saturation can vary from very light (which means very light pink) to vrey bright (wich means vivid red). The saturation reflect the amount of chromium present. Scientifically there is absolutly no other difference between en pink sapphire and a ruby other than the amount of chromium present. In fact if there is something lower than 0,5% the stone is clearly a pink sapphire. Now if its higher than 0,9% probably everybody will be agree to call it a ruby.
But in the between... That's a problem. In Burma for exemple they will by tradition call everything which is red or pink a ruby. And the trade call in the case of a star stone all red and pink corundum star rubies... There is no star pink sapphires...
In fact following my experience buying stones in Burma and working in the gem business in bangkok, many people will buy a stone as a pink sapphire to get a better price and then will try to sell it as a ruby to maximise their profits!

But if the chemistry of the stone is important, the cutting has also its importance as well as the way you look at the stone.
I explain: Corundum is a dichroic stone. It means that the light does not travel at the same speed in all the directions whithin the stone and so as a result depending of the orientation in which you look at the stone a ruby will appear purplish and the orangy if you looks through it. Just experience that to understand the process. So depending the way the cutter place the table may be one ray will be more in favor than the other one. Many people have problem to say like that if the stone is pinkish or purplish at the first glance... But this is one point to take in consideration.
An other point is the fact that the stone is possibly flat. As ruby rough is usualy tabular many stones are cut flat and show in the center a window area. This area does not reflect the light coming from the top and so only the light coming from the bottom of the stone comes to your eyes. As this light will travel less long whithin the stone its resulting color will be less saturated and this window area usulay has one or 2 saturation grade lower than the rest of the stone. So a ruby can be pink in its center (due to the window) and red near the girdle!
Of course a stone can cumulate all that: Have 0,8% of chromium, got a so so orientation and present a window.
You see things are not black or white...

And similar to the controversy with Pink sapphire and Ruby you have the controversy between orange sapphire and ruby and Purple sapphire and ruby as both orange and purple can be present to certain amount in a ruby... The is no fixed worldwide accepted limit for such things!
Ruby trade is not as structured as diamond trade and no ruby grading system impose its rule in the market.
This is just that western passion to classify things with names shows sometimes somes limits: Are you guilty or innocent? Are you right or wrong? It it a ruby or a pink sapphire? Well...

I would say that a nice stone is a nice stone, and if its beauty and price fit to you so all the rest does not really matters isnt'it?

All the best,

 

[valeria101]

----------------
On 1/21/2004 4:36:35 AM mogok wrote:



The is no fixed worldwide accepted limit for such things! [...] It it a ruby or a pink sapphire? Well...

This is just that western passion to classify things with names shows sometimes somes limits:[...]

I would say that a nice stone is a nice stone, and if its beauty and price fit to you so all the rest does not really matters isnt'it
----------------

Thank you for the insight. I could not agree more with you, and, fortunately, at least some of the "westerners" would agree. Oh, and congratulations for the inspired web presence! I am delighted to have encoutered your business this way.

 

[strmrdr]

Welcome to PS mogok.

You hit on something that bugs me the most about the whole issue.

"In fact following my experience buying stones in Burma and working in the gem business in bangkok, many people will buy a stone as a pink sapphire to get a better price and then will try to sell it as a ruby to maximise their profits"

Same with selling purple sapphires that show the slightest hint of red if you hold them just right on the 3rd saturday of the month at high noon on a mountain top as ruby which is even more common around here.

My bottom line is that ruby is red, not pink, purple, orange, or brown and I will preach it from that same mountain! :}

 

[valeria101]

Good luck shopping for the reddest rubies, man! Not sure this really is an East-meet-West issue, but I am rather in the middle of the road from Burma to Boston, and so is my taste and interest in corundum, whatever the name.

I just can't imagine what this theoretical issue could develop into once someone finaly turns towards those Mogok reds on Pricescope hunting for a full blooded ruby instead those pale diamonds.

Time to get off this thread, I guess...

 

[mogok]

Hello,

I finaly get some photos to illustrate better my previous post:

The first stone shows a pink area under the table but a fine red near the girdle. Several persons I've shown the stone and the photo told me for the color: pink! Well... Of course there some pink due to the presence of the so called "window": This area in the center in which the light coming from the top is not reflected to the eyes my goes trought the stone.Only the light coming from under comes to the eye. As this light travels only once into the stone the color looks less saturated and the stones appears pink in this area. But this stone is truly red and cannot obiously be called a pink sapphire!
Well an other good reason for this stone not to be called a pink sapphire is that in fact its a ... Burmese red spinel! (Sorry guys for this trick... lol... But its a good exemple isnt it?)

The trird stone shows a similar problem due to the lighting conditions: This photo was taken using a light box so most of the light illuminating the stone is coming from the side, from behind or under it... Nerly no light coming from the camera position. As all the light is travelling trough the stone once then the stone appears more pink than red!
This stone is in fact a border line ruby: Pinkish Red. But here most of the people will qualify it as a pink sapphire!

The second stone is interesting for the dichoism effect: This is a purplish red ruby but you can discover that the color is not the same everywhere in the stone: some areas are purplish, some areas more red, others pink... This photo was also taken using a light box and the stone is also less pinkish if you look at it with overhead lighting...

Hoping that these photos and the explantions have helped...

Anyway when I see such stone,
As a gemologist I say: This is corundum with Chromium subsitution of aluminium...
As a stone lover I say: That's lovely...
As a dealer I say: How much?

If the answer to the third question fit then the question about should we call these stones rubies, pink sapphire, purple sapphire, or orange sapphire does not matter anymore: It will just be "my stone"...

See You!

Mogok, Bangkok based gemologist

(Note: Photo1: Mogok spinel, Photos 2 and 3 Unheated Mogok rubies)

 

[valeria101]

And the question is... how much red is worth dying for ?

Buyers would have a good reason to be grateful for this debate: it is useful to know the sides and pricing to know just how much disclosure to expect from whatever seller you are inspecting. Both pink and red are precious colors in a rock, fraud is not a good sign of great shopping. Since the color garding syndrom has yet to hit corrundum,

the pricing may still smoothly follow color instead of jumping around grade boundaries like the crazy diamonds do

Thankfully there are not all that many reds to go around and spread the epidemic.

 

[elmo]

Judging from just the photos, I think I'd take the spinel

.

You mention windowing due to the shape of the rough (and to therefore maximize yield and face-up size). I'm curious, with spinel, what is a typical minimum depth percentage in cushion or roundish oval to avoid a window? I looked at one yesterday at around 68% depth that still showed a distinct window but was a fine saturated color otherwise. Price wasn't unreasonable, and I'm still trying to decide how much I think the window detracts from the stone's appearance, and whether some minor recutting might help.

Richard Wise also points out in his book (mentioned earlier) that someone will also cut a window to lighten up the apparent color of an overly-dark stone when viewed in a parcel.

 

[mogok]

Well here are some more pics about spinels:
The first stone is a 5ct Mogok red spinel with a depth around 50% and a resulting brilliance around 50%... This stone is too flat for sure, a fine "bluff" as this stone has exactly the same face as the second stone.
The second one is a 9ct Mogok red spinel with a depth around 80% and an excellent brilliancy around 85%!

Both stones were cut in Mogok, Burma. Native cut not to loose the precious material mixed with superstitions amoung the Mogok cutters. They know how rare are these stones and they also believe in nats (spirits) that can live in their gems. Not to respect these spirits can bring their anger on the cutter... But possibly these spirits are not powerfuls outside Burma and so their stones are recut with profit by foreign dealers.

For me the perfect depth for spinel is around 75% to 80%, but I'm not a cutter so may be somebody else could give you some more informations.

Anyway both of these stones are excellent for different use: The window one was perfectly clean with just a small crystal to prove its natural origin. Set on a gold background it will looks great. The second one is a near perfect stone.
Fine red spinels are more difficult to find than fine rubies so its diificult to be difficult: The problem with these stones is to find them... So rare!

 

[AGBF]

Red Spinel with Pair of Pears

I am seeing if this links to the thread with a picture of my red spinel. I am attempting to follow Josh's instructions! (It didn't work. I did what Josh told me to do, but couldn't put a link to the other thread here .)

 

[elmo]

----------------
On 1/22/2004 8:32:48 AM mogok wrote:

They know how rare are these stones and they also believe in nats (spirits) that can live in their gems.
----------------

The nats(ural) in this case is living just outside the gem there on the girdle

. That's a nice big spinel!

 

[valeria101]

Is THAT your inventory ? Darn... how many =>10cts red spinels like THAT would get out of ground in a year? I haven't got too see all that many 'new' stones in the past three or so

Where are they going?

 

[mogok]

Hello!

Hum I would say it was my inventory... as one of these stones was sold last week!

About the number of 10 carats and over very fine red spinel going out of the ground per year in Mogok... I would say no more than 10 to 20. May be 5...

Let me tell you my opinion about this rarity:

The point with red spinel rarity is that to my knowledge they car only be found in these qualities in Mogok (Burma or Myanmar as you want). If spinels are in Mogok more present than rubies: You find may be 4 spinels for 2 rubies, fine red spinels are much more rare than good rubies in the market.

The reason of the relative abundance of spinels in Mogok compared to rubies is that spinel (MgAl2O4)forms before ruby (Al2O3) Whem magnesium is depleted spinel stop to form and ruby occurs in the metamosphic marbles.

Now regarding to the color of the stones and the rarity of fine red spinels comared to fine rubies: Fine red spinels are very rare as red spinel "sometimes feel attracted by the dark side of the force"

It means that they are too dark (High tone) You will find plenty of "Dark Vador" spinels before to get a fine bright "Jedi" red spinel

. These fine "Jedi" spinels are then falling in the same stories as rubies: Some of them will go too pink (Pink spinels)... other ones too orange (Orange spinels) and finally other one too purple (purple spinels)

Currently to get a top right color 3 carat "Jedi" red spinel is really a hard work!

The reason that makes red spinels so rare in the market are then the following: At the difference with rubies, there are no known treatment to improve a red spinel. So we get only what is coming naturally from the Mogok mines... if 99,9% of the rubies in the market are heat treated 99,9% of the red spinels are not!

Finally the spinel curse is that: Its a very rare stone, with a name that is unknown to the public or that make people think that the stone is a synthetic

(So many synthetic spinel in the market)... So nobody really make any marketing effort on this stone that is probably the most beautiful red stone you can get (

Personnal opinion...)
As diamond spinel is single refractive and
- First they dont get this fuzziness found in ruby due to double refraction.
- Second they have an excellent brilliancy and scintillation when properly cut.
All this make this beauty much cheaper than ruby around the prices of blue sapphires. (I mean when I speak about rubies: Much cheaper than "Mogok Unburned rubies"... )

And one last but not least: Red spinels are as rubies thay have an attraction for inclusions.... Clean, top color, large size red spinels are just so rare that a speciallised dealer in so happy to find a top 5 carat over stone once in a year!

For the rest yep Elmo they is a nat living in the natural on the girdle! lol... But this stone is 9,02 carats and the Nat didn't wanted to weight less than 9 carats!
Thats the point!

 

[Richard M.]

Hello,

Your "from the source" information is very helpful! I'm a spinel lover too, especially reds, but also the incredible range of really unusual colors one can find. The luster of well-finished stones can be amazing! Fine pinks are gorgeous and so are the ones I see described as "flame spinels."

My question is how much orange hue is considered OK in top reds? The 9.2 ct. stone you posted seems slightly orangey on my screen. I know this exercise is imprecise but what is your estimate of the amount of red vs. orange required for "flame" stones? Are they almost pure orange or do they still contain considerable red? An actual flame (I just lit a match) has lots of yellow but I've seen red-tinged flames as well. Any images? Thanks in advance.

 

[valeria101]

I'll try to take this one up...

"Flame spinel" is a traditional name, and has little to do with "fire". it would be hard to compare spinel color with actual flames, since small chemical variations in whatever fuel used (even the type of woods, for example) makes the color of fire get anywhere from yellow to blue, to... anywhere. I might have been able to trace down that "cornflower blue" legend to some rare weed, but there is no way I could guess what were burning the lot who coined this historic trade name in South Asia. This association is clearly not useful.

Trully orange spinels are very rare, and not all that great looking. Yellow spinel do not exist. The only "orange" spinels I know of are either grayish (muddy) or very slightly colored (transparent with a tinge of brownish orange)... not great at all and surely not deserving of the famed "flame spinel" badge of honor.

The famed "flame spinels" are actually red with a more or less strong orange overtone. The name describes top quality spinel, in recorgnition not of it's orange color (as noted above) but of it's more orange overtone relative to rubies of top quality. "Flame spinel" is among spinels what "pigeon blood ruby" is among rubies: just some barely attainable perfection in hue, tone and saturation. I am not sure how suggestive it is to name hues by percentage, but this may be the only way. Spinel is still considered (and looks) red with about 15% orange over red. I doubt this orange component goes to more than 30%-35% in any given stone of gem color.

There is no hard rule about these numbers, and I would gladly welcome any correction regarding them. Their usefulness is limited not by imprecision, but by the scarcity of cerfied spinels... Some orange (as oposed to the rarer violet) overtone does not affect the value/ price of spinel as much as does that of rubies, so hunting down that last 5% is of little interest aside a limited aidience, I hope.

 

[mogok]

Hello Richard and AnA,

Well I nearly 100% agree with what AnA said about "flame spinels" except that the finest quality of red spinels is not "flame spinels" but simply "red spinel"... Which means bright red spinels with a medium high tone and a mimimum or if possible no orange overtone.
Pure red!
Its possible but so damn rare...
Flame spinels are already very rare but true red are really exceptional stones.

Spinel is delicious red stone as its an isometric stone wihtout dichoism that should show a perfect even hue anywhere in the stones. But the reality is different as the cut stones shows some variations of color due to differences between the distance 2 rays of light will have to travel within the stone. This will effect affect the saturation and give some area a lesser red which can go to pinkish. The color is also affected by the fact that dispersion in spinel is not really negligeable and so as a result a red spinel can show some facet with some orange or purplish.
This particularities added to the fact that the stone is not dichoic and so shows a very very high luster makes this stone very very sweet!

Well you have understood that spinels are my little weak point...
All the best! (and if possibly many fine spinels...)

 

[remo]

as someone once told me the term 'ruby' was a loose term for a red gem once it had been cut, coming from the latin word 'rubus' meaning red. (which could describe anything from garnet,tourmaline,spinel or a red variant of any gem).
More commonly applied to corumdum (aluminium oxide) as pure Al.Oxide is colourless the presence of other minerals included when the gem was formed i.e. titanium gives a blue colour to corumdum hence blue sapphire and chromium gives it a red colour. different amounts naturally give different shades/tones.
And as I was told, that a ruby had to contain a minimum of 5% chromium to be classed as a ruby.(I'm not sure if this entirely true or not, but it seems to make sense to me). As amounts above 5% give a phosphorescence under UV light and have a distinct glow in normal light, which is absent in sapphire/corumdum of other colours.
So if this is the case, sapphires having a mixture of elements in their makeup, like titanium and chromium would give the purple colour I've seen in some rubies, so as long as it contained at least 5% chromium, it could be a variety of shades of red and maybe even pink or dark pink.
I guess it is a similar case with green beryllium(beryl) and emerald which has chromium present.(but not in all)there's always an exception to the rule.

Well I hope that helped someone form their own opinion on the subject.

Here's a company that is marketing 'pink'ruby.
WWW.cluff.com.au/html/gemshop2.html

 

[coolguynamek]

Here's pink ruby of 8 carats in a ring. Its really a good thing to look at. I always wear on my finger which looks very attractive.

coolguy

 

[rubydick]

First, for those who have taken images off my website, I am certainly flattered, but please reference the source.

As for Vietnamese rubies, in the early 1990's, some spectacular stones came out of Luc Yen and Quy Chau. Sadly, what has been mined since is only a mere shadow of that.

Regarding the term "pink sapphire," it is a creation of the 20th century and exists because of a linguistic glitch. In English (and many languages), we have two words for red. Light red is "pink," while darker red is simply "red." Regarding blue, we have only one word. Thus a blue sapphire is a blue sapphire no matter how light or dark, but someone mistakenly supposed that pink was not red and thus labelled a pink stone a "pink sapphire." This mistake has sadly continued to the present.

In producing countries like Burma and Sri Lanka, traditionally there was no "pink sapphire." It was all ruby.

For a detailed look at the issue of both pink sapphire and padparadscha, see this link:

Walking the Line in Ruby & Sapphire

 

[Sasori]

Another question guys,
Pink rubies = red sapphires?

Saw a piece of stone I like which is stated as red sapphire.
The seller responded with: "only pigeon blood red corundum are called rubies...The shade of red is not pigeon blood so its call red sapphire"

I've acquired by a colorless diamond, a blue sapphire (can refer to my pics under another thread below) and now looking at my red ruby!
And after which a green emerald.
And I'll have the 4 biggies!