Crafted by Infinity is a brand that is manufactured by Infinity Diamonds, a small cutting house with the aim of cutting the highest quality diamonds in the world. Rather than selling their brand themselves, these diamonds are sold exclusively by several dealers. There are some immediate advantages to this. The first that is evident to me is that the quality of the product will likely be higher because of the additional vetting process by the nature of having more parties involved. Second is that the cutting house is more focused on what they specialise in and don’t have other internal pressures to save costs by retaining carat weight on their diamonds. Third is that the brand probably has some kind of unique look about them that can be immediately recognisable.
As I was browsing the Crafted by Infinity website doing this review, I came across an important point they state on their website; that is, cut grading is in its infancy and unlike color or clarity, what is graded excellent today may not be excellent in a few years time. This can have serious implications on the future value of the diamond you purchase. Of course, you don’t have to purchase an Infinity diamond in order to protect yourself, that is what Prosumer Diamonds is here for. Also, there are many reasons why precision cutting and H&A may never become a recognised superior cut grade by the major labs.
Crafted by Infinity makes an effort to market their diamonds as ‘superideal’. They claim that their diamonds are cut to such rare standards that it is more rare than D color and IF clarity. They make a point to say that they cut ‘only’ 1000 diamonds per year. They say that their brand’s best feature is “Flawless Cut”, which is the only cut grade they aspire to. I have no problems with most of these claims, as they are mostly true. For example, I know that superideal cut diamonds are in the top 1% of all diamonds cut and D-E color diamonds make up around 2% of diamonds.
Although there is also no standard for what a flawless cut is, we do know that most H&A diamonds have minor defects. Diamonds that have several minor defects or a single major defects will not be considered H&A by some vendors. So I can tell how strict a H&A vendor is by how many defects they accept as part of their brand.
I spoke with Paul Slegers, Managing Director at Infinity Diamonds, and he explained to me what they mean when they say their diamonds have a flawless cut is that their standard of flawless craftsmanship is that no defects can be seen under 10x magnification. I think this is fair, considering that GIA grades all other aspects of the diamond under the same magnification power. This is a point that I will bear in mind when I come to reviewing their images below.
On the Infinity Diamonds website, you will find a link to their dealers around the world. As I look through the list, the two vendors I have heard of already are High Performance Diamonds by Wink Jones and Diamonds by Lauren by David Friedlander. Basically, each online vendor will carry the same list of Infinity diamonds for the same price, using the same search engine. Please note that only some vendors offer a 5% wire discount and I would recommend High Performance Diamonds because Wink is one of the more active experts and it won’t hurt to see if he will give you an additional Pricescope discount. The search engine is pretty basic and you can only choose between round and princess cuts, the 4C’s, and price. Lets see if there really isn’t any need to have advanced search functions.
I first notice that there are only about 100 diamonds in total, but I managed to find 6 G to H VS2 diamonds to compare.
It takes a little bit more time than usual to get to the useful information on Infinity’s system. The table, depth, pavilion, and crown information is only visible if you click on a button labelled ‘expert details’. Even then, there isn’t any immediate information about the lower girdle length or girdle thickness information and you have to find that information on the AGS lab report yourself. As far as I can tell, all of the Infinity diamonds are graded by AGS, which has both its positives and negatives, as you will know from previous tutorials. One positive is that Infinity provides AGS lab reports that also have the hearts images. But be aware that the ASET images seen in the AGS lab report is generated digitally and contains potential scanning errors such that it is not a true representation of the diamond but rather a good approximation that cannot replace the actual images.
I collected the data from the 6 diamonds and put in them in the table below:
Infinity Table
As the prices and availability of these diamonds will inevitably change, please visit the source directly for the most up-to-date prices. They also have higher quality images.
1.03 Ct. G VS2
1.09 Ct. G VS2
1.18 Ct. G VS2
1.01 Ct. H VS2
1.05 Ct. H VS2
1.09 Ct. H VS2
All of these diamonds have thin to medium girdles, which helps the 1.01 ct stone to reach that 6.5mm mark that is expected of an ideal 1ct diamond. Apart from this, the only things I can comment on is that the table size is generally between 55% and 57% and each one has a total depth under 62%. From the small sample above, it does not seem like there is a specific pavilion angle that these diamonds are cut to like the Brian Gavin Diamonds stones. This is a positive for those who are looking to squeeze the last bit of carat weight into the diameter of the diamond. The theme of spread continues as I look at the crown facets. All of them are between 34 – 34.5 degrees and this means two things – better spread and increased light return under the table.
Finally I have a look at the lower girdle facets and all but 2 of them have a 78% lower girdle length with the other two 75% and 77%. Although probably not representative of all of their diamonds, I can only conclude that there is not a single contrast pattern of the arrows on all Infinity diamonds and you still have that freedom to choose your preference. It also seems like the lower girdle facets are cut so that they are just under 78.5% lower girdle length in order to achieve a hearts pattern that does not have a clear clef in the middle of the hearts.
So far all of the numbers look good right? Well we know that these numbers only tell half the story so lets get into the hearts image and idealscope images to see how the Crafted by Infinity diamonds hold up to their reputation.
Light Performance
Here are the 6 idealscope images.
table of idealscopes
(The above images are courtesy of Infinity Diamonds, used with permission.)
From a light performance point of view, all of the diamonds above seem to look good in their idealscopes with no visible leakage under the table. The light return also seems very balanced throughout the diamond. Although it may seem like there is no leakage in the upper girdles and that there may be some crown-only painting, it is not the case here as I think this is more to do with photography.
actualinfinity Eightstar
(The use of the above images are courtesy of Infinity Diamonds and Good Old Gold respectively, used with permission.)
For now, you can find the actual picture here and an example of the idealscope from an Eightstar diamond here, scroll 3/4 way down the page.
You can see from the actual image of the 1.03 GVS2 that there is some contrast in the upper girdles, which is eliminated when the girdle is painted. Also compare the idealscope images of the 1.03 GVS2 with the Eightstar diamond that has crown-only painting. You can see that the idealscope images of the Infinity diamonds are clearly not the same.
Optical Symmetry
table of hearts
(This image is courtesy of Infinity Diamonds, used with permission.)
At first glance, the rest of the diamonds seem to have some obvious defects. But it turns out that most of these defects are actually illusions and I would like to thank both John Pollard and Paul Slegers for taking the time and effort to go out of their way to educate me further on the photography issues discussed below. Let me explain with an illustration. The first row of images are computer simulated images of the actual diamond.
camera-tilt
(The above images are courtesy of Infinity Diamonds, used with permission.)
You can see how just 1 degree of tilt in any part of the photography setup (camera lens, body, tripod, table, floor) can create the above illusion. This means we cannot jump to conclusions regarding yaw just because we see some distortion. Please also note that if the setup is perfectly level, the only other thing that can cause this effect is tilt of the table facet. A 1-degree tilt will be caught by the lab symmetry grade, and as Infinity diamonds are all graded excellent symmetry by the AGS, the issue here is not a tilted table facet.
Apart from the first diamond (1.03 GVS2), all the diamonds in my sample seem to be affected by tilted photography. Although this isn’t particularly helpful to us discerning prosumers, it just takes a little more effort to recognise the effect of camera-tilt in photographs. If possible, you should always go and see these diamonds for yourself.
Having studied the above photographs in depth, I have found the best way to detect any yaw that is not an illusion is to find the line of symmetry in the diamond. Once you identify the line of symmetry, you can eliminate the effects of one axis of tilt. Then you can check whether all the V’s are still a bit smaller on one side of the imaginary line of symmetry than the other to determine whether there is tilt in the other axis. Any distortion of the V’s that cannot be explained consistently by camera-tilt will have to be assumed to be yaw, or ‘twist’, which is distortion of the diamond in the azimuth.
Camera-tilt not only causes the illusion of yaw, but also produces what appears to be clefs in between the hearts. You can detect ‘fake’ clefs by noting how close the heart is from the V. If there are hearts in the image that show no clefs but are further from the V, yet hearts that have clefs are closer to the V, then you know that the clefs are illusions from camera-tilt. Looking at the hearts images of the 6 sampled diamonds, I can conclude that all the larger clefs that can be seen are illusions due to camera-tilt.
So now let me get to the minor defects that I see that are not apparently caused by camera-tilt. I will start with the first diamond in the table, which is the 1.03 GVS2. Take a look at the heart at the 12 o’clock position, this heart is slightly smaller than most of the rest. You can see that the gap between the heart and the V is bigger than all the rest apart from the opposing heart. The idealscope tells the story more clearly the larger hotspot in between the second and third arrow is a clear indicator of a smaller heart. In the case of this diamond, the opposing heart appears to be also slightly smaller. Having dealt with camera-tilt above, I would not rule out potential photography issues as the cause of this, but as it stands, this diamond misses the mark as a true H&A in my books.
Now take a look at the fifth diamond, some of the hearts look like they are touching the V’s indicating shorter lower girdles. Correcting for camera-tilt, it seems like the hearts will just barely not touch the V’s. I’m pretty sure that this is the diamond with the 75% lower girdle length as stated on the certificate. Although not a cause for rejection, this may be a consideration for you if you are a H&A purist. Finally, although not a cut issue, I also noticed an inclusion that reflects around the pavilion in the third diamond, what is known as a ‘reflector’. This is not good for a VS2 diamond and you can definitely find better.
Having considered all the information, and inspecting the hearts images of all 6 diamonds thoroughly, I have come to the conclusion that notwithstanding the camera-tilt, it is apparent to me that at least 5 out of the 6 diamonds are cut to the highest level of precision and are deserving of the super-ideal qualification.
Price
The price of a Crafted by Infinity diamond carries a price premium that is expected of a top-of-the-line super-ideal H&A brand. A comparison with the online vendors that move far greater volumes of diamonds just doesn’t seem fair. Remember that Infinity Diamonds primarily targets showroom clientele and viewed in this light, their prices are justified and even provide greater value than other popular brands (Tiffany, Cartier, Hearts on Fire, etc). I’m just glad to see that outfits like High Performance Diamonds are still providing an opportunity for online consumers access to these diamonds.
Value Added Services
As Crafted by Infinity is not a retailer themselves, each of their dealers will have their own value added services so I will not go over them here. There is one interesting value add that Crafted by Infinity provides and that is their ‘Meet the Cutter’ events. This gives a chance for any Infinity owner to go to any one of their dealers who is holding one of these events where they get to meet the person who cuts their diamond. Diamond prosumers should find this an interesting and valuable chance to learn about diamonds so if you’re lucky enough to be in the area of one of the dealers, then this may be something worth your consideration.
Conclusion
I had a great time doing this review, not only did I learn a lot more about Infinity Diamonds, which I hope I have successfully conveyed on to you, I also learned a lot about how market trends and photography has changed the diamond industry.
I found that the diamonds I reviewed had excellent spread for a well-cut diamond so you will get a good sized diamond for the stated carat weight. If spread is important to you and you want a super-ideal diamond then Crafted by Infinity may be a good option for you. The diamonds I reviewed also tend toward the brighter side of my recommended range of proportions rather than the dispersive side. Their excellent spread is due to their attention given to the thin to medium girdles, close to 56% table percentage, 40.7-degree pavilion angles, and close to 34-degree crown angles.
The only problem that I identified with Infinity Diamonds is with their photography setup, as the camera-tilt makes it harder for consumers to make online purchasing decisions. If you need help interpreting any of their images online, please feel free to send me an email and I will try my best to help you out. I hope that Infinity Diamonds will be able to one day improve the quality of their photography.
I want my readers to appreciate the investment that is needed in order to produce high quality pictures and that it can be a burden on a small cutting house such as Infinity Diamonds. If you have any concerns regarding optical symmetry, Wink Jones at High Performance Diamonds, who carries the Crafted by Infinity brand has a ‘See It To Believe It” (SITBI) program where you can see the diamond for yourself before you buy it.
The bottom line is that if you’re looking to seek comfort from a reputable brand name who produces some of the best looking precision cut diamonds in the world, then you should consider a diamond that is Crafted by Infinity. I recommend those seeking a Crafted by Infinity diamond to demand nothing short of top-of-the-line optical symmetry that is expected of their cutting house and brand.
Friday 30 August 2013
Thursday 22 August 2013
Pricescope Rockytalky Review: Aprilbaby
It’s time for another Pricescope Rockytalky review!
I noticed yet another recent thread that had an interesting question about Whiteflash ACAs. The specific question was whether all ACAs are made exactly the same and would PSers ever recommend against one? The question was raised because of concerns that the ASETs and Idealscope of some ACAs, in particular those under half a carat, varied a bit and that some idealscope also showed what appears to be leakage.
You can read the original thread here.
The short answer would be no they are not all made exactly the same and Whiteflash does not claim that they are. The simple reason being that there are always going to be borderline cases, and you would also expect the rare but unavoidable human error. The general answer is that yes, if you purchase a Whiteflash ACA, it is very highly likely that you will be a satisfied customer. The full answer, however, would require some knowledge of how a diamond is cut, which is going to be the topic of a future tutorial. For now, it is sufficient to know that diamonds cut to super-ideal standards are precision cut, and the cutter is usually able to cut the diamond very precisely. Also, if you’ve read all my tutorials, you will know precisely how each facet affects the appearance of diamond. Equipped with this knowledge, you too would expect there to always be an explanation for what you can see in any image of a diamond whether actual or light performance related.
In the thread, three ACAs in total were brought up for discussion. The first two were compared first:
Diamond 1
http://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-2684406.htm
Diamond 2
http://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-2982215.htm
The first question about these two diamonds was whether Diamond 1 had a better idealscope than Diamond 2. The person who posed the question thought that Diamond 2’s ASET was more dull and the idealscope was more grey and less vibrant. The more experienced PSers handled the question well noting that you should not be comparing the color saturation of different ASET images with each other.
However, no one seemed to look more carefully to see what else could explain the differences seen. Without even looking at the idealscope, you can see that Diamond 1 has more contrast around the edge of the diamond. This is because Diamond 2 has slightly painted girdles. This is of course verified by looking at the idealscope and what I believe is the proper answer to why the idealscope appeared more grey is actually because it has more deep reds in the upper girdles. It is often difficult for untrained eyes to distinguish dark-greys and deep reds in idealscope images. The ASET also tells the same story and you can see it manifesting as ever slightly increased green areas, lengthening in the upper girdles and thickening around the stars facets.
Does the existence of slight painting change what I think about ACAs? Certainly not, because it still exuberates a familiar characteristic contrast pattern under the table facets. You can think of slight painting as a sprinkle or topping to the diamond that you can choose whether to go with or without. Be minded that the reason slight painting is used here is most likely to ensure the diamond is over 1ct in weight.
The next comparison was between Diamond 2 and Diamond 3 below:
Diamond 3
http://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-2949573.htm
Interestingly, Diamond 3 is a good example of why an ASET tells a clearer story than the idealscope. Untrained eyes are not likely to notice the widening of the leakage areas around the edges indicating steeper upper girdles in an idealscope image. The upper girdles are not so steep that they cause obvious leakage, but under the ASET, it is clear that at least 10 of the 16 upper girdles are steep enough to be returning light from the periphery (green on the ASET). A further inspection of this diamond’s proportions confirms that this is not what I am used to seeing in a typical ACA. Because of this, I had a quick peruse of some of the other ACAs under half a carat and I noticed that there is more variation in proportions in these smaller diamonds than there are for diamonds 1ct and above.
Now I can see how these diamonds still make it to the ACA level, after all, they are still well within my recommended proportions, with precision cut H&A, and near 100% light return. The subtlety here is that where the light return is coming from in the upper girdles is more from the periphery rather than from around a 45 degree angle, the latter in my opinion is preferable. This diamond does not have the best edge to edge light performance and is likely to pick up all sorts of color reflecting from its surroundings.
The conclusion of this review is that most ACAs are made the same, but there are some borderline cases, which I personally would avoid if I were purchasing an ACA. If you are looking for an ACA and have any doubts/questions. Please feel free to send me an email or leave a comment.
I noticed yet another recent thread that had an interesting question about Whiteflash ACAs. The specific question was whether all ACAs are made exactly the same and would PSers ever recommend against one? The question was raised because of concerns that the ASETs and Idealscope of some ACAs, in particular those under half a carat, varied a bit and that some idealscope also showed what appears to be leakage.
You can read the original thread here.
The short answer would be no they are not all made exactly the same and Whiteflash does not claim that they are. The simple reason being that there are always going to be borderline cases, and you would also expect the rare but unavoidable human error. The general answer is that yes, if you purchase a Whiteflash ACA, it is very highly likely that you will be a satisfied customer. The full answer, however, would require some knowledge of how a diamond is cut, which is going to be the topic of a future tutorial. For now, it is sufficient to know that diamonds cut to super-ideal standards are precision cut, and the cutter is usually able to cut the diamond very precisely. Also, if you’ve read all my tutorials, you will know precisely how each facet affects the appearance of diamond. Equipped with this knowledge, you too would expect there to always be an explanation for what you can see in any image of a diamond whether actual or light performance related.
In the thread, three ACAs in total were brought up for discussion. The first two were compared first:
Diamond 1
http://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-2684406.htm
Diamond 2
http://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-2982215.htm
The first question about these two diamonds was whether Diamond 1 had a better idealscope than Diamond 2. The person who posed the question thought that Diamond 2’s ASET was more dull and the idealscope was more grey and less vibrant. The more experienced PSers handled the question well noting that you should not be comparing the color saturation of different ASET images with each other.
However, no one seemed to look more carefully to see what else could explain the differences seen. Without even looking at the idealscope, you can see that Diamond 1 has more contrast around the edge of the diamond. This is because Diamond 2 has slightly painted girdles. This is of course verified by looking at the idealscope and what I believe is the proper answer to why the idealscope appeared more grey is actually because it has more deep reds in the upper girdles. It is often difficult for untrained eyes to distinguish dark-greys and deep reds in idealscope images. The ASET also tells the same story and you can see it manifesting as ever slightly increased green areas, lengthening in the upper girdles and thickening around the stars facets.
Does the existence of slight painting change what I think about ACAs? Certainly not, because it still exuberates a familiar characteristic contrast pattern under the table facets. You can think of slight painting as a sprinkle or topping to the diamond that you can choose whether to go with or without. Be minded that the reason slight painting is used here is most likely to ensure the diamond is over 1ct in weight.
The next comparison was between Diamond 2 and Diamond 3 below:
Diamond 3
http://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-2949573.htm
Interestingly, Diamond 3 is a good example of why an ASET tells a clearer story than the idealscope. Untrained eyes are not likely to notice the widening of the leakage areas around the edges indicating steeper upper girdles in an idealscope image. The upper girdles are not so steep that they cause obvious leakage, but under the ASET, it is clear that at least 10 of the 16 upper girdles are steep enough to be returning light from the periphery (green on the ASET). A further inspection of this diamond’s proportions confirms that this is not what I am used to seeing in a typical ACA. Because of this, I had a quick peruse of some of the other ACAs under half a carat and I noticed that there is more variation in proportions in these smaller diamonds than there are for diamonds 1ct and above.
Now I can see how these diamonds still make it to the ACA level, after all, they are still well within my recommended proportions, with precision cut H&A, and near 100% light return. The subtlety here is that where the light return is coming from in the upper girdles is more from the periphery rather than from around a 45 degree angle, the latter in my opinion is preferable. This diamond does not have the best edge to edge light performance and is likely to pick up all sorts of color reflecting from its surroundings.
The conclusion of this review is that most ACAs are made the same, but there are some borderline cases, which I personally would avoid if I were purchasing an ACA. If you are looking for an ACA and have any doubts/questions. Please feel free to send me an email or leave a comment.
Thursday 1 August 2013
Pricescope Rockytalky Review: Icycherry
It has been quite a while since I’ve made one of these Pricescope Rockytalky reviews. There is good and bad to this. The good thing is that I’ve noticed in general better responses to people’s questions. The bad thing is that it is also because it seems like less people are asking interesting questions.
Here is a post I came across that I found interesting because it is typical of the responses that are given to those seeking expert advice, yet they are being turned away by telling the original poster that they cannot nitpick without more detailed information. When reading this the first time, I felt that I could give the original poster the kind of advice he was seeking and that is why I chose his question for a review.
Here is how the thread went:
Posted by Icycherry on July 31st, 2013, 10:03 pm
“Hi guys,
I’ve got a diamond produced in Canada, which has very good figures (at least to the eyes of a newbie): 61.9%depth; 55%table; 34.5crown angle and 40.8pavilion. What bothered me was the star and lower half, which was 45% and 75%. Would this combo affect the fire (which I highly care) and brilliance of the stone? I have heard that if the star is smaller, it should go with a steeper crown. It seems that 34.5 is not steep enough. Appreciate any opinions!” (Emphasis Added)
Posted by Icycherry on August 1st, 2013, 10:20 am
“Here are the more detailed figures of this stone:
1.72carat; measurements: 7.69-7.71*4.76; Depth: 61.9%; Table: 55%; Crown Angle: 34.5°; Crown Height: 15.5%; Pavilion Angle: 40.8; Pavilion Depth: 43.0%; Star Length: 45%; Lower Half: 75%; Girdle: Medium, Faceted (3.5%); Culet: None
The report is issued by GIA.(That might be a great problem ’cause the figures are rounded ones, not accurate enough) I understand that it would be uneasy to tell exactly how this would affect the performance of the stone just by figures, but I really have no way to see the stone before I pay for it. So….still want to hear some opinions, even conjecture would be greatly appreciated.”
<h2>Best Pricescope Rockytalky Responses:</h2>
Posted by John Pollard on August 1st, 2013, 9:52 am
“On its face 55-40.8-34.5-45-75 is not an issue. But it depends on how specific you want to get.
Impossible to say more because, aside from table, the data points are averages of 8-16 separate measurements apiece. Those averages are further rounded up-or-down if it’s a GIA report. From this data there’s no way to know how consistent the cutting is facet-by-facet, if that is important to you.”
Posted by Yssie on August 1st, 2013, 10:56 am
“Here’s a tutorial from Good Old Gold that introduces LGF and star (link removed)
The numbers are what the PS community would call “safe” – worth further investingation. But what you’re asking… well, garbage in, garbage out! GIA rounds star and lgf to 5%, crown to 0.5deg, pav up to 0.2deg, and the numbers printed on the report are averaged around several sections of the stone as Mr. Pollard said…
And to add to those uncertainties are other errors: the Sarin scanners GIA uses in the labs are listed (on the Sarin webpage) as accurate to +/- 0.1deg, the GIA report tells us nothing about optical symmetry (the symmetry of the reflections of facets you see when you look into the stone – it’s a function of facet meet symmetry but there are other parameters)…
IMO your best friend in this situation is an idiot-proof return policy. Or buying from a boutique vendor who specialises in exactly this sort of nitpicking – GOG, WF, BGD, Infinity (sold by HPD) are the first PS favourites who come to mind.”
<h3>My Comments:</h3>
Now John Pollard is a trade member who works at Crafted by Infinity. He knows a lot about diamonds and I have personally learnt a lot from his previous posts. Although his post was accurate, it doesn’t help the original poster by telling him there is insufficient information. In fact, his response led to Icycherry to believe that a diamond certified by the GIA may be a great problem when the GIA is the most respected lab in the world. This, of course, was not John Pollard’s intention, but that is what happens when trade members post without addressing all of the key concerns of the original poster.
Yssie, who is a diamond prosumer with 16116 posts to date responded by saying that the numbers were ‘safe’ – I find this generalisation dangerous for a newbie. There is further scaring of the newbie with more rounding and measurement errors without indicating what kinds of risks are safe and what are not. Is the best advice here an ‘idiot-proof’ return policy? Yssie’s second piece of advice is to purchase from basically any one of several PS vendors…
<h3>My Response to Icycherry’s question:</h3>
Icycherry first lists the proportions of the major facets of his chosen diamond and states that these are “good figures”. He has obviously done his base research on proportions. The problem he has is mainly with the lower girdle percentage and the star percentage, which are 45% and 75% and he wants to know whether these numbers raise any red flags because he has a preference for fire.
Although in most cases when referring to the star and lower girdle facets, I would bring up measurement errors, in this case I actually think that it may not be necessary. Yes there may be some slight variation in the proportions, but the question asked is not about optical symmetry and the variances are not likely to be so large as to invalidate any reasonable advice.
The diamond Icycherry has chosen has an excellent length and width 7.69-7.71mm and has a CA/PA of 34.5/40.8 with a 55% table, it sounds like a fairly promising stone. What she needs to be aware of is that the shorter the stars, in general the shallower the stars are. Also, with shallower stars, the upper girdle facets are also shallower. With 45% stars, there is a likely chance that the upper girdle angle is less than 40 degrees. The effect that this will have on the diamond is that there will be less contrast in the upper girdles. Also with 45% stars, the bottom half of the diamond will appear noticeably darker than one with 50-55% stars. The point is that these are diamonds with different contrast pattern character.
The edge of this diamond would probably look a bit like a diamond with a painted upper girdle:
smallstars
If Icycherry prefers the contrast pattern of the 45% stars, then the risk that Icycherry needs to know is that if the stars tend to the shorter side, say 42.5%, there will be quite a bit of unnecessary weight lost.
Also, with 45% stars and a 75% lower girdle length, we would not expect many hotspots around the base of the arrow shafts. If these facets are even shorter than stated, then you may lose the triangular hotspots under the stars as well. All this means a detriment to a further detriment to ‘pin’ fire in the diamond. With 75% stars, the diamond is already not optimised for pin-fire but rather for more bold flashes. If that’s the only thing Icycherry cares about, then the lack of pin-fire flash could make the bold flashes stand out more.
If it is the case that these facets tend to 47.4% and 77.4%, then the diamond becomes more typical of a TIC and there is not many concerns. In fact, coupled with the proportions of the major facets, I would expect this potential possibility to have excellent light return.
As for whether the crown facets should be steeper? Well the crown facets do not work that closely with the star facets except for perhaps physical constraints. The advice Icycherry probably heard was that because shorter stars generally reduce fire, then going for a steeper crown could make up for some of that. The thing that is misleading in this sort of advice is that although a steeper crown produces more dispersion from the crown, it has no bearing on the potential fire that could have been produced by the star facet. These are two different things.
My advice to Icycherry is to first figure out which kind of fire she prefers (bold or pin flash fire), and then to optimise for it throughout the diamond. If it is the case that she likes pin-fire flash, then perhaps going for 45% stars and 75% lower girdles may not be the best choice. If Icycherry happens to read this, I hope you have found my conjecture to be a bit more helpful than the responses you’ve received from the other Pricescope experts.
Here is a post I came across that I found interesting because it is typical of the responses that are given to those seeking expert advice, yet they are being turned away by telling the original poster that they cannot nitpick without more detailed information. When reading this the first time, I felt that I could give the original poster the kind of advice he was seeking and that is why I chose his question for a review.
Here is how the thread went:
Posted by Icycherry on July 31st, 2013, 10:03 pm
“Hi guys,
I’ve got a diamond produced in Canada, which has very good figures (at least to the eyes of a newbie): 61.9%depth; 55%table; 34.5crown angle and 40.8pavilion. What bothered me was the star and lower half, which was 45% and 75%. Would this combo affect the fire (which I highly care) and brilliance of the stone? I have heard that if the star is smaller, it should go with a steeper crown. It seems that 34.5 is not steep enough. Appreciate any opinions!” (Emphasis Added)
Posted by Icycherry on August 1st, 2013, 10:20 am
“Here are the more detailed figures of this stone:
1.72carat; measurements: 7.69-7.71*4.76; Depth: 61.9%; Table: 55%; Crown Angle: 34.5°; Crown Height: 15.5%; Pavilion Angle: 40.8; Pavilion Depth: 43.0%; Star Length: 45%; Lower Half: 75%; Girdle: Medium, Faceted (3.5%); Culet: None
The report is issued by GIA.(That might be a great problem ’cause the figures are rounded ones, not accurate enough) I understand that it would be uneasy to tell exactly how this would affect the performance of the stone just by figures, but I really have no way to see the stone before I pay for it. So….still want to hear some opinions, even conjecture would be greatly appreciated.”
<h2>Best Pricescope Rockytalky Responses:</h2>
Posted by John Pollard on August 1st, 2013, 9:52 am
“On its face 55-40.8-34.5-45-75 is not an issue. But it depends on how specific you want to get.
Impossible to say more because, aside from table, the data points are averages of 8-16 separate measurements apiece. Those averages are further rounded up-or-down if it’s a GIA report. From this data there’s no way to know how consistent the cutting is facet-by-facet, if that is important to you.”
Posted by Yssie on August 1st, 2013, 10:56 am
“Here’s a tutorial from Good Old Gold that introduces LGF and star (link removed)
The numbers are what the PS community would call “safe” – worth further investingation. But what you’re asking… well, garbage in, garbage out! GIA rounds star and lgf to 5%, crown to 0.5deg, pav up to 0.2deg, and the numbers printed on the report are averaged around several sections of the stone as Mr. Pollard said…
And to add to those uncertainties are other errors: the Sarin scanners GIA uses in the labs are listed (on the Sarin webpage) as accurate to +/- 0.1deg, the GIA report tells us nothing about optical symmetry (the symmetry of the reflections of facets you see when you look into the stone – it’s a function of facet meet symmetry but there are other parameters)…
IMO your best friend in this situation is an idiot-proof return policy. Or buying from a boutique vendor who specialises in exactly this sort of nitpicking – GOG, WF, BGD, Infinity (sold by HPD) are the first PS favourites who come to mind.”
<h3>My Comments:</h3>
Now John Pollard is a trade member who works at Crafted by Infinity. He knows a lot about diamonds and I have personally learnt a lot from his previous posts. Although his post was accurate, it doesn’t help the original poster by telling him there is insufficient information. In fact, his response led to Icycherry to believe that a diamond certified by the GIA may be a great problem when the GIA is the most respected lab in the world. This, of course, was not John Pollard’s intention, but that is what happens when trade members post without addressing all of the key concerns of the original poster.
Yssie, who is a diamond prosumer with 16116 posts to date responded by saying that the numbers were ‘safe’ – I find this generalisation dangerous for a newbie. There is further scaring of the newbie with more rounding and measurement errors without indicating what kinds of risks are safe and what are not. Is the best advice here an ‘idiot-proof’ return policy? Yssie’s second piece of advice is to purchase from basically any one of several PS vendors…
<h3>My Response to Icycherry’s question:</h3>
Icycherry first lists the proportions of the major facets of his chosen diamond and states that these are “good figures”. He has obviously done his base research on proportions. The problem he has is mainly with the lower girdle percentage and the star percentage, which are 45% and 75% and he wants to know whether these numbers raise any red flags because he has a preference for fire.
Although in most cases when referring to the star and lower girdle facets, I would bring up measurement errors, in this case I actually think that it may not be necessary. Yes there may be some slight variation in the proportions, but the question asked is not about optical symmetry and the variances are not likely to be so large as to invalidate any reasonable advice.
The diamond Icycherry has chosen has an excellent length and width 7.69-7.71mm and has a CA/PA of 34.5/40.8 with a 55% table, it sounds like a fairly promising stone. What she needs to be aware of is that the shorter the stars, in general the shallower the stars are. Also, with shallower stars, the upper girdle facets are also shallower. With 45% stars, there is a likely chance that the upper girdle angle is less than 40 degrees. The effect that this will have on the diamond is that there will be less contrast in the upper girdles. Also with 45% stars, the bottom half of the diamond will appear noticeably darker than one with 50-55% stars. The point is that these are diamonds with different contrast pattern character.
The edge of this diamond would probably look a bit like a diamond with a painted upper girdle:
smallstars
If Icycherry prefers the contrast pattern of the 45% stars, then the risk that Icycherry needs to know is that if the stars tend to the shorter side, say 42.5%, there will be quite a bit of unnecessary weight lost.
Also, with 45% stars and a 75% lower girdle length, we would not expect many hotspots around the base of the arrow shafts. If these facets are even shorter than stated, then you may lose the triangular hotspots under the stars as well. All this means a detriment to a further detriment to ‘pin’ fire in the diamond. With 75% stars, the diamond is already not optimised for pin-fire but rather for more bold flashes. If that’s the only thing Icycherry cares about, then the lack of pin-fire flash could make the bold flashes stand out more.
If it is the case that these facets tend to 47.4% and 77.4%, then the diamond becomes more typical of a TIC and there is not many concerns. In fact, coupled with the proportions of the major facets, I would expect this potential possibility to have excellent light return.
As for whether the crown facets should be steeper? Well the crown facets do not work that closely with the star facets except for perhaps physical constraints. The advice Icycherry probably heard was that because shorter stars generally reduce fire, then going for a steeper crown could make up for some of that. The thing that is misleading in this sort of advice is that although a steeper crown produces more dispersion from the crown, it has no bearing on the potential fire that could have been produced by the star facet. These are two different things.
My advice to Icycherry is to first figure out which kind of fire she prefers (bold or pin flash fire), and then to optimise for it throughout the diamond. If it is the case that she likes pin-fire flash, then perhaps going for 45% stars and 75% lower girdles may not be the best choice. If Icycherry happens to read this, I hope you have found my conjecture to be a bit more helpful than the responses you’ve received from the other Pricescope experts.
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