Heated vs. Unheated Sapphire

[brightblue]

HELP. I have been lurking here for a few weeks and would appreciate some of your expertise. I have found a 1.5 ct. sapphire at a local jeweler in a setting I love. The stone is nice, but as most sapphires are, heat treated. I have also looked at TNSC''s site extensively and read reviews on this forum. First, does how difficult is it to have a stone fit into an existing setting? Second, what do you think of this? I want a beautiful blue sparkle...

http://www.thenaturalsapphirecompany.com/Sapphires/Blue/B929/Cushion/stoneid=B929

Also, does a sapphire glow more in a prong setting vs. a bezel? I teach kindergarten so I am very tough on my hands.

Thanks

 

[RevolutionGems]

Fitting a different stone into a setting depends entirely on the setting itself. If the prongs or bezel are incorporated into the design, a different sized stone won''t fit. If the prongs or head are only attached (soldered) into the setting like a solitaire, all the jeweler has to so is swap it out for the properly sized head.

Your best bet would be to talk to your jeweler and let him know what you want to do. He will be the one that can tell you if the stone cam be easily replaced.

I will leave the sparkle question to the other experts here. But I will say that you have exquisite taste in stones!

 

[Barrett]

NSC

 

[chrono]

I always recommend finding the stone first, then the setting because finding the right colour and shape is difficult enough without having to add the limitation of physical dimension. Even though the sapphire at your local jeweller is 1.5 ct, you’ll need to make sure you know the sizes of stone that will fit into the setting. When it comes to coloured stones, a 1.5 ct sapphire can measure anywhere from 6.5 mm all the way to 7.5 mm depending on the cut and depth while settings usually have only have a “give” of 0.5 mm range at both ends.

The glow of a sapphire depends on the stone itself, so having it prong set or bezel set will not affect it that way. A darker toned stone will benefit more from a more open prong setting while a lighter toned sapphire can appear to look richer in a bezel setting. Of course a bezel setting is more protective of the girdle area as well.

While you didn’t ask the question of heated versus unheated in your post, I presume you meant to ask about it since that is the title of your thread? Does it matter to you that it is heated or unheated? Your options certainly open up greatly with a heated stone and it will also cost less. However, it you want an unheated stone, by all means go that route. Note that unheated sapphires don’t necessarily look better than a heated sapphire (with a few exceptions).

 

[brightblue]

Yes, I did mean to ask about heated vs. untreated stones. I want to say I am not a purist...but if that were true I would have already purchased the ring I have found. It is by no means an heirloom piece, but it is my ring which will be worn every day. My question..does it matter?

 

[chrono]

Deciding whether to get a heated or unheated stone is a very personal decision that can only be decided by an individual as the heating of sapphires has long been an acceptable practice in the trade. Heating of blue sapphires removes the green and sort of helps it where Mother Nature didn’t quite complete the work. Or you can select a stone based on exactly how Mother Nature made it herself. I have seen both heated and untreated stones passed down through the family line or worn just for fun. Perhaps you weren’t particularly attracted to the colour of the sapphire at the local store or there was something else bugging you about it other than the heat/no heat issue?

 

[Jim Rentfrow]

Its exactly what Chrono said, its a personal choice. While the percentage of corundum that is heated is in the high 90''s percentage wise, a lot of people still prefer to have an unheated stone. It is entirely up to you, and you can always make additional purchases in the future.

 

[Arkteia]

In general, much as I prefer unheated stones, I''d say, go with what you like about it. Because it''s you who are going to wear it. Little use knowing that it is unheated if you don''t like the color or something else about the stone! I have seen very many unheated sapphires of beautiful "cornflower" color but with a strong grey modifier; I passed on them. Of course, heated sapphires are or should be much cheaper. If it is heated, the price should reflect it.

I remember LD who is such a gem afficionado mentioning several times that she had been looking for a sapphire of the right color for years and finally bought a heated one but the color was amazing and she bought it at a fraction of its cost. I now keep it in my mind as a viable choice.


There is a different question the answer to which I do not know. Perhaps Chrono or other gurus should know. Likely it doesn''t pertain to your situation, but still...I always heard that Kashmir sapphires have "sleepy" appearance because of presence of rutile inclusions in them. Now assuming that heating breaks rutile threads, would it affect the overall look of Kashmir sapphires?

 

[Cind11]

Date: 3/10/2010 11:20:13 AM
Author: crasru
In general, much as I prefer unheated stones, I''d say, go with what you like about it. Because it''s you who are going to wear it. Little use knowing that it is unheated if you don''t like the color or something else about the stone! I have seen very many unheated sapphires of beautiful ''cornflower'' color but with a strong grey modifier; I passed on them. Of course, heated sapphires are or should be much cheaper. If it is heated, the price should reflect it.

I remember LD who is such a gem afficionado mentioning several times that she had been looking for a sapphire of the right color for years and finally bought a heated one but the color was amazing and she bought it at a fraction of its cost. I now keep it in my mind as a viable choice.


There is a different question the answer to which I do not know. Perhaps Chrono or other gurus should know. Likely it doesn''t pertain to your situation, but still...I always heard that Kashmir sapphires have ''sleepy'' appearance because of presence of rutile inclusions in them. Now assuming that heating breaks rutile threads, would it affect the overall look of Kashmir sapphires?

I am sure that heated sapphires are less expensive but I am not sure if the "much cheaper" is always true. I have a sapphire cut by Richard Homer, and it was far from inexpensive. His prices may be higher, but the color, cut and the polish on the stone is amazing.

 

[chrono]

Cind11,
My statement of a heated sapphire being less expensive than a heated sapphire is when comparing 2 stones of similar quality (colour, cut, origin, size, clarity, etc). The difference in price increases or decreases when other factors come into play; rarity, larger carat weight, and of course, precision cutting. Part of the higher price charged by Richard Homer is not just for the material but the excellent cutting and polish.

 

[Michael_E]

Date: 3/10/2010 8:22:48 AM
Author:brightblue
First, does how difficult is it to have a stone fit into an existing setting?

It''s easy if the two stones are similar in size and shape. It''s much more difficult to impossible if they are different sizes/shapes.

Second, what do you think of this? I want a beautiful blue sparkle...
.
.
Also, does a sapphire glow more in a prong setting vs. a bezel?

"Glowing" in a gemstone can only occur if the stone has microscopic inclusions which diffuse the light in the stone slightly OR the stone has a strong fluorescence. Stones which are extremely clear can be very sparkly, but they usually don''t glow. If a stone does glow, then the type of setting used to hold it does not affect the glow, (or the sparkle for that matter).

I teach kindergarten so I am very tough on my hands.

I''d make sure to get a setting which is as low as possible and probably fairly well protected from loosening as well. This means fairly heavy construction, as light weight bands and prongs can be easily bent in a tough environment. Heavier prongs are also much smoother if rubbed against sensitive skin than small, light prongs. Bezels are even smoother and it''s nearly impossible to lose or loosen a stone in a well made bezel setting.

 

[Arkteia]

Date: 3/10/2010 12:46:32 PM
Author: Cind11

Date: 3/10/2010 11:20:13 AM
Author: crasru
In general, much as I prefer unheated stones, I''d say, go with what you like about it. Because it''s you who are going to wear it. Little use knowing that it is unheated if you don''t like the color or something else about the stone! I have seen very many unheated sapphires of beautiful ''cornflower'' color but with a strong grey modifier; I passed on them. Of course, heated sapphires are or should be much cheaper. If it is heated, the price should reflect it.

I remember LD who is such a gem afficionado mentioning several times that she had been looking for a sapphire of the right color for years and finally bought a heated one but the color was amazing and she bought it at a fraction of its cost. I now keep it in my mind as a viable choice.


There is a different question the answer to which I do not know. Perhaps Chrono or other gurus should know. Likely it doesn''t pertain to your situation, but still...I always heard that Kashmir sapphires have ''sleepy'' appearance because of presence of rutile inclusions in them. Now assuming that heating breaks rutile threads, would it affect the overall look of Kashmir sapphires?

I am sure that heated sapphires are less expensive but I am not sure if the ''much cheaper'' is always true. I have a sapphire cut by Richard Homer, and it was far from inexpensive. His prices may be higher, but the color, cut and the polish on the stone is amazing.

Agree, I should have said, "all other factors considered". But your stone is from a museum-grade cutter who also chooses good material, so it likely turned out museum-grade. This being said, I consider Richard Homer''s prices "high", not "higher" (LOL).

 

[brightblue]

I have looked at Richard Homer''s stones-they are amazing for sure. I guess patience is the key here. Any comments on the sapphire from TNSC in my earlier post? The setting I am looking at has six prongs in a solitaire-sounds like it may not be strong enough for my lifestyle. I appreciate all these perspectives.

 

[LD]

Date: 3/10/2010 3:15:18 PM
Author: brightblue
I have looked at Richard Homer''s stones-they are amazing for sure. I guess patience is the key here. Any comments on the sapphire from TNSC in my earlier post? The setting I am looking at has six prongs in a solitaire-sounds like it may not be strong enough for my lifestyle. I appreciate all these perspectives.

I''m not going to comment on colour/cut/clarity/price BUT I will comment on the dimensions of the stone. When you buy "off the shelf" settings, they are made for calibrated gemstones i.e. 7 x 5, 6 x 4, 9 x 7, 8 x 6 etc etc. The dimensions of the stone you''ve linked to are 6.90 x 5.62 x 4.27.

Most settings if prong set (and this does not work with bezel set settings where there is virtually no tolerance), you can fit a gemstone so that you have .5mm difference. So, looking at your stone, you could find a setting with a 7mm length and that would be great. The problem comes with the width with this stone. If you bought a 7 x 5, it would be great for the length but would overhang each side too much - if the setting has a halo or side stones, the sapphire will sit on top of them. If you went for an 8 x 6 setting, the width would be better and probably more manageable but the length would be too long.

None of the above is important IF you have the setting customised but that increases price and so depends on your budget.

 

[Indylady]

If you''re still on the hunt, check out Multicolour (great inventory!) and Africagems, Mastercutgems, Finewater (you''ll have to send Gary an email), Precision Gem (same, shoot Gene and email), Swala Gem Traders (same, an email) and Dutton''s Diamonds.

 

[Pandora II]

Date: 3/10/2010 11:20:13 AM
Author: crasru
In general, much as I prefer unheated stones, I''d say, go with what you like about it. Because it''s you who are going to wear it. Little use knowing that it is unheated if you don''t like the color or something else about the stone! I have seen very many unheated sapphires of beautiful ''cornflower'' color but with a strong grey modifier; I passed on them. Of course, heated sapphires are or should be much cheaper. If it is heated, the price should reflect it.

I remember LD who is such a gem afficionado mentioning several times that she had been looking for a sapphire of the right color for years and finally bought a heated one but the color was amazing and she bought it at a fraction of its cost. I now keep it in my mind as a viable choice.


There is a different question the answer to which I do not know. Perhaps Chrono or other gurus should know. Likely it doesn''t pertain to your situation, but still...I always heard that Kashmir sapphires have ''sleepy'' appearance because of presence of rutile inclusions in them. Now assuming that heating breaks rutile threads, would it affect the overall look of Kashmir sapphires?

A true ''Kashmir Sapphire'' would show the ''silk'' (the rutile inclusions that cause the sleepy look) - I did read about a famous gemmologist who said that the finest ''Kashmir Sapphire'' he ever saw was from Madagascar.

If you are talking about sapphires from Kashmir then they don''t always have silk. They can be as varied as sapphires from any other location. The famous ''Kashmir Sapphires'' from Kashmir were all mined out by early in the 20th Century IIRC.

If you were to heat one of these, then yes the rutile inclusions would be destroyed and the stone would look different. Too much silk can also make a stone look cloudy. Lots and lots makes a stone a good candidate for a star stone.

I bought some sapphires with spectacular silk from some mineowners in Sri Lanka - the colour was fine enough that they didn''t heat them. I also bought some heated stones that don''t show rutile inclusions.

Having both, I would say that it''s a personal decision. I love to get my loupe out and look at the lattice of rutile inclusions twinkling away in my unheated stones, but the colour of the heated ones is pretty good to look at too. From a distance I honestly couldn''t tell which was which.

For an engagement ring I''d probably push the boat out for unheated just because I like inclusions, but if I wanted a particular colour and I could only have it if I went with heated then I wouldn''t feel I''d picked second-best or anything like that.

For my gem collection it would have to be unheated. For any other jewellery, I''d choose heated as I''d get the look for less lucre!

 

[Sagebrush]

All,

It is fair to say that 95% of blue sapphire in the market is heat treated. There are levels of heat treatment based upon the temperature used, however, there is little difference in prices as perceived by the market, it is either heated or not. The material heated, called sic. geuda, is a usually a light grayish white silky material with lots of rutile, the look is known as "diesel". Heating will not remove the green component, that is a function of orientation of the stone''s table relative to the axis of the crystal.

Given two fine sapphires the normal price differential between heated/non-heated will be 50+ plus, the ratio increases dramatically with the fineness of the material and also with origin, Burma and Kashmir will command premiums based entirely on geographic origin.

The "glow", sleepy appearance, in a Kashmir sapphire (as well as some Sri Lankan stones) is caused by submicroscopic inclusions that are not resolvable by a standard gemological microscope @ 160X. It is called "flour" or "snow" This is not rutile (in Kashmir), rutile is normally not found in Kashmir sapphire. Rutile (crystalline Titanium oxide) is responsible for the "foggy" appearance is some Sri Lankan sapphire and Burma ruby, it lacks the fineness necessary to produce the subtle glow so desired by connoisseurs.

 

[Pandora II]

Date: 3/10/2010 4:59:48 PM
Author: Richard W. Wise
All,

It is fair to say that 95% of blue sapphire in the market is heat treated. There are levels of heat treatment based upon the temperature used, however, there is little difference in prices as perceived by the market, it is either heated or not. The material heated, called sic. geuda, is a usually a light grayish white silky material with lots of rutile, the look is known as ''diesel''. Heating will not remove the green component, that is a function of orientation of the stone''s table relative to the axis of the crystal.

Given two fine sapphires the normal price differential between heated/non-heated will be 50+ plus, the ratio increases dramatically with the fineness of the material and also with origin, Burma and Kashmir will command premiums based entirely on geographic origin.

The ''glow'', sleepy appearance, in a Kashmir sapphire (as well as some Sri Lankan stones) is caused by submicroscopic inclusions that are not resolvable by a standard gemological microscope @ 160X. It is called ''flour'' or ''snow'' This is not rutile (in Kashmir), rutile is normally not found in Kashmir sapphire. Rutile (crystalline Titanium oxide) is responsible for the ''foggy'' appearance is some Sri Lankan sapphire and Burma ruby, it lacks the fineness necessary to produce the subtle glow so desired by connoisseurs.

Thanks for that Richard, but can you explain why it is so often said that ''silk'' is a desirable quality if it doesn''t lend a glow. Is it just a common misconception, or is the term ''silk'' used for inclusions other than rutile?

Also, would the submicroscopic inclusions in a Kashmir sapphire be altered by heat-treatment or completely destroyed and so alter the look of the stone?

 

[Sagebrush]

Hi Pandora,

Had a discussion about silk just the other day. Dick Hughes, the author of the seminal book Ruby And Sapphire, challenged my four Cs of Connoisseurship (color, cut, clarity, crystal) at the 2/24 Bangkok GIA event where I lectured, based on his belief that silk inclusions can be a plus particularly in ruby and of course, Kashmir sapphire. His point, lots of small bits of silk (rutile) fractures and dissipates the light waves as the bounce off the back facets of the pavilion on the way back out the crown and to the viewers eyd. This, together with the ultraviolet fluorescence in ruby, causes a sort of visible reverberation affect or "glow" that he finds highly attractive. He believes that this look is superior to the "crystalline" purity of a clean stone, one with good crystal and therefore an exception to my rule.

My point; the more perfect the underlying diaphanity of the stone, i.e. clear as a mountain stream, the more effective the reverb. Problem is most rutile is, in fact, either too large or too dense and the overall affect is to fog up the look of the stone and impede light transmission. The market clearly prefers a more "crystalline" gem. Since he wrote the book, his opinion is widely respected and probably the source of what you are speaking of.GIAhttp://www.giathailand.com/Gemstone%20Gathering%20February%2010.html

 

[Pandora II]

Thanks, that makes sense now.

When is he going to re-publish his book??? I''ve been on the waiting list now for YEARS! It''s £655 GBP a copy on UK Amazon at the moment!

 

[Sagebrush]

Pandora,

Well as to a new edition of Hughes'' classic, I am not sure. My wife and I had dinner with Hughes and his wife last week. Spent a couple of hours at his apartment going over his book collection and talking books. His knowledge of antiquarian gem books is truly encyclopedic and, as usual, listening to him is an education. They took us to a wonderful little home style Thai restaurant in his neighborhood, great oysters!

His book is going for over $1,000 per copy most places. He is right now working on publishing a 19th Century book on ruby and his normal answer to queries about a new edition of R&S is, "I''m working on it." Unfortunately all the plates were lost by his original printer so the entire book will have to be redone from scratch and that is expensive.

Stay tuned!

 

[brightblue]

Loving Diamonds-Thanks for the info. re: how a stone might or might not transfer to an existing setting. A bezel just sounds more sturdy. I like a halo but I want the blue to be prominent. IT''s all about the blue for me.
INdy Lady posted other vendors that deal in colored gems-I don''t know why these sapphires or so much lower in price. Anyone?
Also all, thanks for the clarification re: "Glow" and "Sparkle". As I am a rookie, I may not have used these terms correctly.

 

[chrono]

A blue stone will still stand out in a halo setting as long as the colour is eye popping. It all depends on the saturation. As for the price difference, NSC is well known for charging higher prices than other places.

 

[brightblue]

I have just discovered the James Meyer settings. Is there enough light in a bezel setting? I am still uncertain of my heated/unheated choice, but am on the prowl for colored gem I like, then will be able to make that decision. I was surprised at the comment that unheated sapphires were not significantly more costly than unheated. I was under the impression that there was a big price difference.

 

[threegraces]

I *think* mine is heated, I really am not sure because DH picked it out. I say, aside from not wanting to pay more than fair value, who cares? Go with what you love and what you can afford, don''t be influenced by what other people think a stone should be. 99.9% of the world doesn''t know nor care about gem treatments, they know if something is beautiful or not.

And I wanted to share my blue since you were wondering how it would look in a halo. I prefer a prong vs a bezel to let the light in and show it off.

 

[threegraces]

And since I can''t figure out how to attach more than one file or upload pics, here''s another shot in the car not long after I got the ring. It''s not very clear but you can see how the sun lights it up.

 

[threegraces]

One more

 

[Arkteia]

Beautiful stone, and beautiful shot! (True grace!),

Would you mind telling me the specifics of the stone?

 

[threegraces]

I can tell you what I know (I was told I need to start a thread in the SMTR thread) about it.

It''s a Beverly K setting. You can see the setting here, although that''s not where we got it: http://www.pearlmansjewelers.com/jewelry-designers/beverley-k-jewelry/rings/109PP1/42/

The sapphire is a AAA quality cornflower blue sapphire 7.22 x 7.25mm 2.04 carats (says the insurance appraisal).

DH bought it from Topazery.

 

[T L]

Date: 3/10/2010 8:22:48 AM
Author:brightblue
HELP. I have been lurking here for a few weeks and would appreciate some of your expertise. I have found a 1.5 ct. sapphire at a local jeweler in a setting I love. The stone is nice, but as most sapphires are, heat treated. I have also looked at TNSC's site extensively and read reviews on this forum. First, does how difficult is it to have a stone fit into an existing setting? Second, what do you think of this? I want a beautiful blue sparkle...

http://www.thenaturalsapphirecompany.com/Sapphires/Blue/B929/Cushion/stoneid=B929

Also, does a sapphire glow more in a prong setting vs. a bezel? I teach kindergarten so I am very tough on my hands.

Thanks

I don't think anyone has mentioned beryllium diffusion of sapphires (I skimmed the posts, so I could be wrong). This is a way to introduce color artificially into the stone via chemicals. They are heated as well, and not to be confused with stones that undergo regular routine heat. Be-heated stones are very inexpensive, around $5/ct, and only a reputable gemological laboratory would be able to determine if the stone was be-heated. They can look fabulous as well, so don't be deceived by appearances. I would not buy a sapphire from any jeweler without a lab report indicating the level of treatment, especially if it was for an e-ring. Even jewelers that know their sources can be duped.