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About davidelevi

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    Ideal Diamond

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  1. FWIW, it seems fairly 'lifeless' and without contrast in the video. Whether that's because of the video technique or because the stone actually shows that way is a different question.
  2. It worked for me right now - GIA website problem? https://www.gia.edu/report-check?reportno=5211299763
  3. davidelevi

    Advice emerald cut diamonds GIA/0.7/0.9Ct

    Indeed not! Stay safe, and post more pictures when you can!
  4. davidelevi

    Advice emerald cut diamonds GIA/0.7/0.9Ct

    I wish I could tell you for certain. 🙂 Is that in red what you are referring to? It seems like a whole chunk is missing from the side... which would be very difficult to do by cutting! So I suspect it's just an effect due to the setting below the stone becoming visible (and the stone not being very good, so you actually see the setting)... However, all this said, it could only be an artefact of the photo. Is that something that you have seen 'in reality', or just a couple of photos the vendor has sent you? I would recommend you taking the photos as close as possible (with the diamond remaining into focus!), and then cropping the resulting photo just around the diamond before pasting it into the post. This way we can get maximum magnification.
  5. Perfectly reasonable price. Let us know what you think once you get the stone!
  6. davidelevi

    Overwhelmed Novice

    I'm sorry. It sounded definitely aggressive to me - I felt being questioned on the appropriateness of the comparison, when it was a requested comparison. I have misinterpreted your tone; always a risk in writing. I did genuinely mean you do not have to qualify a question, as long as @operamom is happy with her thread being highjacked every now and then - or rather often. Keep asking, and I'll do my best to understand the tone - and answer bringing value if I can.
  7. davidelevi

    Overwhelmed Novice

    Any diamond not bought from her store would look cloudy. Obviously. GIA has had a fair amount of flack piled on them since their massive expansion a few years ago as it decreased the prized consistency across labs that had always been a GIA hallmark. Some of it deservedly - but they seem (IMHO) to have got things under control and are back to 'normal service'. Even the shameless enabler that is me suggests letting things take the time they need. As you have seen, there is no scarcity of suitable stones - and that's just looking at a couple of vendors. In the meantime, if you have any questions or even just want to 'talk diamonds', go ahead!
  8. That is BS. What is true is that setting it may cause microscopic damage to the finish and it would no longer qualify as IF. Since there is typically a fair amount of money between VVS1 and IF (all else being equal), they may not want the responsibility, but there are no structural issues with any diamond just because it is graded IF. If anything, the absence of inclusions visible at 10x and the fact that the surface has polished up nicely without leaving graining lines or pitting - both necessary to get an IF clarity grade - would indicate the opposite! There is nothing wrong with it - but colour sensitivity and taste are very individual things. Especially in a relatively large stone, you may see some tint through the side when observed against a white background. The cut is fine, although there is some weight 'hidden' in the crown, to get the stone over the magical 2 carat barrier. Assuming you paid a fair price, whether you should return it really depends on whether you like it... and only you can be the judge of that!
  9. davidelevi

    Advice emerald cut diamonds GIA/0.7/0.9Ct

    If the big black below the keel (the sharp edge at the bottom of the stone) is just due to the photograph angle (i.e. it's not there permanently or most of the time as you rock the stone back and forth and from side to side), then it's much better than the other one. Is it the right one for you? Only you can decide. Clarity - in my opinion it's one of those things that you have to do up to the point where you are happy that you don't see or worry about the inclusions, whether that's I2 or VVS1. It varies significantly from stone to stone, and from person to person. But going above brings no visual benefit: you just pay for rarity. If you are happy with VVS, absolutely fine - I would just encourage you not to think that there are no VS (or even SI) stones without bothering inclusions.
  10. davidelevi

    Advice emerald cut diamonds GIA/0.7/0.9Ct

    The problem is that there is very little on a lab report that tells you (or us) whether the stone is well cut or not. The only way to really address this is to see it. FWIW, from the two photos that you posted, if they look anything like the stone typically does in reality, that is a really poorly cut stone. The big advantage of living in Antwerp is that you can probably see a lot of other ones quite easily! Don't be rushed into making a decision too soon, and keep looking. When you find 'the one' you will know it. Also FWIW, I would be much less worried about fluorescence than you seem to be. You may find this GIA article interesting to read: https://www.gia.edu/gems-gemology/winter-1997-fluorescence-diamonds-moses Final note: I don't know what diamonds 'with weird inclusions' you may have seen, but VVS clarity is usually overkill - it is definitely paying € for something you can't see.
  11. davidelevi

    Overwhelmed Novice

    I am comparing two stones that the OP was considering. I would also advise you to moderate your aggression. You have been treated with nothing but the utmost courtesy here, and your tone is perpetually passive-aggressive.
  12. davidelevi

    How can i get best custom Jewelry manufacturing service in us?

    A ringing (!) endorsement by a nonsense poster. Great recommendation.
  13. davidelevi

    Overwhelmed Novice

    That is always a good plan - Covid permitting. I would also suggest that colour is not the only thing you want to test: size and cut quality seem to be pretty big drivers for your upgrade plan too. No point in paying for things you don't value. For colour, you may find the results of this interesting: https://www.xrite.com/hue-test It's not a substitute for a proper colour discrimination test in a controlled environment, and neither are meant specifically for gem colours, never mind diamonds, but I think it's quite revealing nevertheless. If you want to have a bit of sadistic fun, you can ask your husband to take the test too, and revel in your superiority (statistically, at least - don't take it out on me if he has the eyes of a hawk - or of a mantis shrimp!). If in addition to average person we stipulate average observation conditions, the honest answer is 'no'. No way. BTW, the difference is nearly $17k. On average, we look at a diamond ring for a few seconds at a fair distance and random angle, the ring is in a setting on somebody else's hand - and that hand is usually moving, the diamond usually isn't spotlessly clean (even just putting it on and taking it off will add a film of skin oils), the light is all over the place as are background colours, and the average person doesn't have a 'ready reckoner' in their mind based on experience about colours, cut and size that would enable a comparison with another diamond that they saw a few minutes/hours/days/months ago in another place. Taking the two diamonds from the vault, cleaning them and setting them next to each other on a viewing tray and under a diamond light, the average person (without a loupe) observing carefully would notice fairly quickly that one is whiter and slightly larger. The proportions are close enough that even switching lighting to jewellery spotlights and moving the diamonds around they would look very similar in the amount and type of light they reflect. With a loupe, and if you draw 'the average person's' attention to it, they would probably notice that the larger diamond is also a smidgen more symmetrical and very slightly brighter on the periphery. Adding the BN 2.30 F/VS1 to the tray would probably result in the following observations: as white as the whiter WF (F to G is visible, but 'on average' only through the side in controlled lighting), appreciably (but not hugely) smaller than the other two, less contrasted and less symmetrical. A little less bright and a little less lively/sparkly/fiery - not hugely, but noticeably. A lot of people would not (and do not - Blue Nile sells many more diamonds than Whiteflash) see "$6,000 worth of difference" between the 2.30 and the 2.45 even though pretty much all would agree that the 2.45 is a 'more valuable' diamond - just not $6,000 more valuable for many. My anecdotal observations suggest that if you ask them 'why do you prefer the 2.45, regardless of price' most people would say that it is larger, more lively and beautiful. However, I would expect that bringing in the 2.32 I/VVS would result in most people not seeing $11,000 worth of difference between the 2.32 and the 2.30 either... and walking out with the 2.32 and $11,000 (or $17,000) more in their pockets.
  14. davidelevi

    Yellow Diamonds and Fluorescence

    Much the latter. Not least because colour is a much bigger driver of prices than 'cut quality' defined as liveliness and contrast (and possibly symmetry). In addition, fancy colours are much more often cut as non-rounds (for various reasons - colour transmission being one), which makes the whole concept of 'ideal proportions' rather cumbersome to apply. FWIW, I would disagree that there are 'ideal proportions' for pretty much any diamond - a modern 'superideal' isn't necessarily more beautiful than an old cut. Potentially yes - but I haven't seen enough Tiffany coloured diamonds to say whether this is generally the case. Also, while depth is a driver of weight vs. size, there are other ways of hiding weight in a diamond that don't necessarily involve depth, and lastly depth% is significantly influenced by the aspect ratio: if you take a square-girdle diamond it will have a lower depth % than a rectangular-girdle one of the same volume (weight), all else being "equal". This is purely mathematical and means nothing in terms of appearance.
  15. davidelevi

    Overwhelmed Novice

    You don't need to qualify a question. 🙂 Short and flippant version: By understanding what fire is, and looking for it. In the immortal words of Justice Potter Stewart, "you'll know it when you'll see it". YMMV. (this is less flippant than it seems - people's visual acuity and visual training varies a lot!) Longer version - and unflippanting (?) of the short version: ******************** Warning - seriously nerdy post below; read at your own peril ********************* **************** Do not read while driving; it may cause somnolence or drowsiness ****************** ************************ Contains personal opinions as well as verified facts ************************* It depends on what you mean by 'measured quantities' - and there is some interesting history behind this, dating back a few decades or even hundreds of years depending on the perspective you take. In Europe, diamonds have been cut to improve their aesthetic qualities at least since the 14th century - and for at least a millennium longer and according to rather different aesthetic criteria in India. Several cut innovations were introduced over the next 5 centuries and people generally agree that (say) a Peruzzi cut looks 'more beautiful' than a table cut or a rose cut. However, systematic analysis of 'diamond beauty' is much more recent and can be said to start with Tolkowsky's analysis in 1919. If one thinks of a gem as an optical system made of a set of mirrors and a set of prisms, it is obvious that the more mirrors there are, and the more those mirrors are oriented so as to send white light back to the observer's eye, the more light is reflected. It is equally obvious that the more prisms there are and the larger those prisms are, the higher the chance that optical dispersion will cause white light to become visible as coloured rainbows, which are generally taken as beautiful. Because the gem has a finite volume and surface area, the more mirrors you have, the smaller the prisms get, and the larger the prisms, the fewer the mirrors can be. The problem is that while optimising reflection or dispersion individually is relatively easy, it is also not very interesting or beautiful to see. A flat mirror is rather boring, and a prism isn't very bright (and is pretty boring too after the first sight, let's be honest). In very rough terms, this is the issue that gem cutters face: how to get the balance between directly reflected and dispersed light in such a way as to make the gem beautiful and interesting: if they put too many mirrors in, it turns into a static mirror, and if they put too many prisms in, there isn't enough light returned directly to make the gem visible; a subsidiary problem is that you also need to orient the mirrors to reflect both direct and dispersed light from many directions into the eyes of an observer. Add in the fact that gem rough is usually very expensive and the market prizes large gems, and you have a relatively difficult problem to solve. By the 1900s, cutters were well aware of the inherent trade off between pure reflection ('brilliance') and dispersion ('fire') in a refractive material and Tolkowsky attempted to optimise the balance of the two partly by obtaining his results purely mathematically, but partly by observing and justifying what were considered 'attractive' proportions and angles that were being cut in everyday practice. The first AGS cut grade, introduced IIRC 1996, used Tolkowsky's "theoretical" results as an 'absolute best' or 'ideal' set of proportions, any significant deviation from which was penalised by assigning a lower cut grade - regardless of whether it actually caused a decrease in objective variables (e.g. percentage of light returned) and/or subjective assessment of 'beauty'. Note that Tolkowsky had already pointed out that other combinations of parameters than his 'ideal' 40° 45' / 34° 30' pavilion/crown angle combination would produce equally good results from a mathematical standpoint and in practice - he listed proportions for stones that were observed by him and others in the trade to produce "the liveliest fire and the greatest brilliancy", and while the average measurements accorded with theory (there's lies, damned lies and statistics), there were pretty significant variations within the sample: pavilion angle varied from 40° to 41° and crown angle from 33° to 35° in a sample of only 5 stones chosen for their overall beauty (and thus presumably looking relatively similar in terms of the amounts of reflection and dispersion observed). GIA started with a similar approach in the 1990s, when they investigated a number of different methods to measure reflected light ('brilliance') and dispersion ('fire') as a function of stone proportions, using a variety of light sources/patterns and observation-point weightings in an attempt to model and reproduce human visual impressions which were gathered separately from multiple people from different backgrounds (from consumers to diamond experts). By the early 2000s GIA changed tack (although they claim they didn't - I don't particularly believe that there was a 15 year research plan at the outset), and rather than attempting to model beauty in terms of separate parameters they asked trade experts to rate various diamonds for beauty without necessarily relating these to separate concepts or standardised measurements of brilliance and fire. Partly as a result of that it became clear that other parameters/variables were relevant to an assessment of beauty (scintillation, contrast, symmetry/pattern, polish/finish) and cut quality (size, weight, durability), and that a wide combination of proportions could be combined to give 'beautiful' results. This turned into the current GIA cut-grading system, which takes relatively few 'key' parameters about the stone in relatively broad sets of combinations, and provides an overall assessment of cut quality without reference to the underlying "visual" aspects of brilliance, fire, scintillation and contrast, although it acknowledges it used them to develop the scoring algorithm. GIA (to my knowledge) never published the data, correlations and detailed findings of its 'first part' research, so while there may be a fair few methods of reliably and repeatably measuring brightness and dispersion in a (near-)colourless diamond and the corresponding metrics relating them to human observation - including information on the thresholds of observability and how that relates to exposure and training - they are buried in some GIA database somewhere. Meanwhile, AGS developed (possibly inspired by the GIA research of the mid-1990s) a series of processes and models for measuring light return in various fashions, including 3-D ray-tracing (using technology originally devised for CGI effects in movies), which constituted the basis for its heavily revised cut-grading system, issued in 2005 and evolved since, which incorporates explicit assessments of brightness, brilliance, contrast, scintillation and dispersion (and quite a few other parameters). Unfortunately, while the AGS algorithm is commercially available, its details are not public - and (again, as far as I know), the individual parameters and the methodologies for assessing/measuring them are not only not public, but the individual raw results are not disclosed as part of the standard software output. Neil (DenverAppraiser) is a senior AGS member, and may be able to provide more information (and correct any errors in my write-up, not just about AGS). Other technologies and methods have been developed to measure various aspects of light return and make them more easily quantifiable. These range from reflector scopes (Ideal-scope, Firescope, Diam-Xray, ASET, H&A viewer) to software models (HCA) to relatively complex machines (Brilliancescope, Sarine Light). Unfortunately none of these fulfils three criteria that in my view would be necessary to make direct, widespread, consumer-friendly use of these technologies in measuring fire, brilliance and sparkle in real-life: Standardisation of tools, methods and metrics Sufficient granularity of metrics and scales/sensitivity to input conditions Transparency of algorithms and methods So, back to your questions: Are there commonly agreed definitions for fire, brilliance and sparkle? Yes. Are the physical mechanisms at the base of these metrics well understood? Yes. Are fire, brilliance and sparkle measurable objectively? In principle yes - although there is significant lack of alignment as to how (e.g. should an observer head shadow be taken into account in measuring these?) Are there commonly agreed units and methods of measurement for those things? No. Can a person assess these 'subjectively' (i.e. without instruments) but with good reliability? The answer seems to be yes, from the GIA studies. These also showed that training was important, but not necessarily a driver of sensitivity ("members of the public" did as well as trade experts at measuring variations in brightness and dispersion, but trade experts were on average more consistent in their assessments, IIRC) Lacking an agreed standard for measuring these things, you either decide to put your trust in a specific methodology and use that consistently (which may be as simple as trusting that the "someone" is actually being honest and competent - honest and competent people do exist, and a few even work in the diamond industry, you know? 😉), or you rely on your subjective impressions at the moment of assessment, possibly supported by well established physical principles (e.g. taller crowns mean 'larger prisms', which should translate into more fire) - however the risk of confirmation bias would suggest that first the observation result should be recorded unaided, then matched against physical measurements and finally confirmed. There really is no less flippant answer than 'you'll know it when you see it'. Even where there are well-established and repeatable measurement methods (e.g. diameter), the non-instrumental observability of the difference depends heavily on the context: isolated vs. simultaneous observation (side-by-side), lighting, background, observation angle and distance, observer's visual acuity and physical fitness, initial assessment vs. recall on second exposure. Yes, it's as fickle as that. *********************************************************** To relate this to the current case, if you are latching onto my observation that and are indirectly asking how confident I am in making this statement, the answer is fairly strongly. I have seen several thousands of diamonds, including hundreds cut by 'premium cut brands' (Whiteflash, Brian Gavin, Crafted by Infinity, Hearts on Fire, Eightstar and others). While sometimes the cut of the 'non premium' diamond is of comparable overall quality (precision, symmetry, polish) to the 'premium', this happens rarely, and in most cases the difference is visible with a loupe and often to the naked eye, even if the average proportions on the lab report match quite closely. For example, the BN stone in question does not seem to show a well defined '8-point star' when photographed straight on; the WF stones all do, and in my experience this is visible in real life. The JA 'True Hearts' shows an 8-point star in the centre, but the arrow heads are inconsistently contrasted - more difficult to observe, but possible if you remember to look for it (and correlated to the asymmetry in the crown evident in the ASET image). Does that make either the BN or the JA an 'uglier' stone? No - and they do cost less (per carat if not overall). It does make the WF stone more likely to perform 'better' on things like subjectively perceived sparkle and fire, where symmetry and regularity of pattern seem to matter.