- Black areas indicate light returned at very high angles. These areas are dark in the ideal-scope because light is blocked from above eg: the lens, eye or camera.
- Red areas indicate the brightest light returning to the eye. (if your scope has a different colored lower collar then the that same applies) eg: I personally have a scope with a Blue Collar so I’m looking for Intense Blue.
- Pink areas indicate less intense light return. (see above if your collar color is different to Red)
- White or grayish areas indicate light escaping, or ‘leaking’ out of the diamond’s pavilion and not being returned to the eye.
How to read ideal scope images
Originally Invented in Japan during the 1970’s, Dr Kazumi Okuda invented what is called the ‘Fire Scope™’ . Basically the tool used a white light source that floods the pavilions of Round Brilliant Cut Stones . Sitting around and above the stone was a cone of red paper which is also illuminated from the light below. Gemstones are viewed through a top 10X maginfying lens via a hole in the red cone. This was the begining to estimated how much light was being transmitted and refracted from the pavillion of Gemstones.
In 2001 , Garry Holloway a fellow Australian made and a hand held device that had a larger area of pink encompassing all light illuminating the crown. This new instrument is sold and marketed as the Ideal-Scope and demonstrations can be viewed at www.ideal-scope.com. There are many other Scopes on the market that are similar.
The intensity of red, together with the amount of white (light leaking from behind the stone), indicates a diamonds face up light return. Blackness indicates the darkened area of light that originates from, and returns to the lens. This approximates the darkness cast by an observer with head that blocks a 31° or illumination for the Fire Scope™ and a more realistic 24° for the Ideal-Scope.
Experienced users can interprete the black patterns of darkness that originate from the lens and assess the symmetry and scintillation of a diamond. Diamonds that exhibit a symmetrical star shaped black pattern are by definition ‘optically symmetrical’ and if that blackness is evenly dispersed and covers approximately 10 – 20% of the stone then the diamond will display pleasing scintillation.
And lets face it, all the top Diamond Dealers are using this technology when trying to sell you you a Diamond. There aren’t many Jewelery shops that offer Ideal Scope and Asset Scopes images for you to view. Some might have the actual scopes for you to use, but if you are doing this for the first time, you may miss things, like the overall symmetry or small indiscretions in the arrows or hearts. James Allen Diamonds offer great Ideal scope images with their True Hearts collection, Brian Gavin’s Signature Hearts & Arrows Collection only shows one Ideal Scope image of the ‘Hearts’ through the pavillion but they do offer an Aset Tool Image showing the ‘Arrows’, which I think is adequate. My pick would have to be Whiteflash Diamonds, with their collection ‘A CUT ABOVE® Hearts and Arrows’. Their full disclosure of images is excellent, you can view a 360 degree video, a normal face-up view, two Ideal Scope Images showing Hearts and Arrows, an Aset Tool image plus the Diamond Report you can view to double check all the angles.
“In my experience any diamond that displays an exceptional Ideal-Scope image is ‘ideal cut’ by definition, what ever its proportions.”
Garry Holloway (FGAA, DipDT, JAA Appraiser)
Ideal Expert Scope
10x Expert 'Ideal Scope' Hearts and Arrows Viewer
Ideal Scope IMages
Pictured above is an ideal cut diamond, showing Hearts and Arrows viewed under an Ideal Scope. The symmetry shown in this diamond is definately Ideal, and about the best you could hope for.
The DNA of Hearts & Arrows
There are five components required in creating an Ideal Hearts and Arrows Diamond. Originally this was designed to improve a Round Brilliant Cut, but we now have Princess and Cushion Cut Diamonds that exhibit Hearts and Arrows. Not quite the same but they are there non the less. Of particular reference is that excellent polish and symmetry alone is not enough to qualify for the all important podium of ‘Hearts and Arrows”. Cutting Hearts and Arrows is very difficult. The H&A pattern is only found on stones that have been cut with a high degree of patience and time. Hence the overall price increase compared to a Diamond that does not exhibit Heart and Arrows. Because of the high degree of symmetry and the limited proportion sets for which the patterns are visible, cutters often settle on cutting for GIA Excellent or some other premium cut instead of committing the time and weight loss necessary to produce an ideal cut Hearts and Arrows diamond. Hearts and Arrows is ONLY acheived when these five components are correct and all working in harmony together.
Hearts and Arrows matrix in ROund Brilliant Cut Diamonds
Combinations of RED will not work. Combinations of YELLOW can work but with very narrow combinations of Table size and Star lengths Combinations of GREEN will exhibit H&A, Bold H&A indicates the best angles to look for. Box’s showing RED H&A combinations are doubtfull
Pictured above is a H&A Matrix. Cutters now know that the Table Facet must be between 54-57% of the overall size of the Diamond. Once in this area the Crown Angle and the Pavillion Angle also must be within a certain degree’s. The BOLD H&A in the middle of the Green is where we find the best Optical Symmetry, thus producing the best Hearts and Arrows.
Pictured above is a breakdown of all the facets required in a modern Round Brilliant Cut Diamond. Cutters know that all these components of a cut diamond be accurate in order for the symmetry required to produce H&A diamonds.
Pavillion Angle - 1
Pavilion Angle: range 40.2° – 41.2° (40.6° – 40.8° is optimum)
The most important factor in light performance in diamonds is proper Culet and Pavillion angles. Tolkowsky orginally stated that pavilion angles of 40.75° were optimal. EVen now with modern technology this figure is still correct and within the parameters. The pavilion main facets are like eight mirrors all angled in such a way to reflect light that enters a diamond at vertical angles from 0° to 15° from it’s axis. When the pavilion main facets of a diamond are angled too steep, they will not reflect maximum light back to the viewer. In fact, when these angles exceed 41°, the shaft part of the arrows begins to disappear. It is difficult to have bright evenly colored arrows in the H&A viewer, as these facets are beginning to reflect off the walls of the viewer instead of the white ring at the top. “Angle symmetry”, which refers to all of the facets of a group being cut at the same angle, is imperative in maintaining optical symmetry, so that all eight arrows “light-up” at the same time.
Crown Angle - 2
Crown angle: range 33.4° – 36.4° (34° – 35° is optimum)
The crown angle works in harmony with the pavilion angle. If the pavilion angle is slightly steeper than optimum, a shallower crown angle must compensate for this. Conversely, a shallow pavilion angle can be balanced with a slightly steeper crown angle. However, a combination of a steep crown angle and a steep pavilion angle creates problems and would never be found in an H&A stone. See above for the optimal Crown and Pavillion angles with the Matrix.
Table Size - 3
Table Size: 53% To 58% (54%-57% is optimum as seen in the above Matrix)
The table size of a diamond affects both light performance and the Hearts and Arrows Pattern. In the arrows view, the table size affects the size of the table reflection (star) in the center of the stone at the culet. a 60% Table also causes issues with the Hearts affecting the top shape. A table of 55% indicates how the heart’s tops are squared-off and improved by the smaller table.
Lower Girdle Halves- 4
Lower Girdle Halve length: 75% To 80% (77% is optimum)
The secret behind optimal Hearts and Arrows pattern lies in the precision creation of these 16 facets of the pavilion. These parameters are crucial in if cutters are to acheive the perfect hearts. These carefully cut facets produce the eight main pavilion facets that build the foundation work for the entire hearts and arrows creation. It is vital that all lower girdle halves are cut to exactly the same length and angle, or the resultant pavilion mains will vary in size and shape and will create crooked hearts and crooked arrows.
Star Facets- 5
Star Facet Length: 40% To 58% (45%-50% is optimum)
Star facets can be overlooked by a number of Cutters, but the length of these can have a positive or negative influence depending on their size. In the heart view, the star facets round off the Top Lobes of the hearts, which directly relates to the size of the table. In the arrows view, each star facet contains two small pairs of triangles that are visible between the eight arrowheads. see image below. Long star facet lengths will create problems in cutting the Hearts and Arrows, thus making it not ‘Ideal’. If the star facets are too long, they will create the negative effect called “clustering, side or interference figures”. This disturbs the typical pattern of the arrowhead and shaft area of the eight arrows by adding white reflections that alter the normal H&A pattern.
“Clustering” or interference figures can be exaggerated by a combination of long star facets greater than 55%, lower girdle halves greater than 77% along with steeper pavilion angles. This negative factor makes the arrows pattern unacceptable. The “perfect arrows view” below is much cleaner in appearance due to star facets that fall between 45%-50%.
Now that we’ve gone through ‘How to read Ideal Scope images’, whilst the indepth information is incredibly important and extremely relevant to Diamond Mines, Factories, Cutters and their wholesale buyers, most of it is not required when buying a diamond online. We are interested in the final overall CUT we are presented with. If you are looking for “Hearts and Arrows’ ROund Birlliant Cut Diamonds, use the Matrix above, please ‘Double Check’ that the Diamond you are looking at on the screen is in fact the actual image and not a ‘Photoshopped’ image. ‘Double Check’ the Diamond Certification Report, it will have all the angles you can check and verify that is the Diamond you are looking at.
Lets look at the Matrix for this Diamond to see if it could be a Hearts and Arrows:
- Table Size: 55.8% (this is in the Optimal Range)
- Crown Angle: 34.6 (Looking good
- Pavillion Angle: 40.8 (It should be a good diamond)
- Lower Girdle Half: 77% (great)
- Star Facet: 52% (not optimal but very very close)
As I mentioned at the start of this article, My pick would have to be Whiteflash Diamonds, with their collection ‘A CUT ABOVE® Hearts and Arrows’. Their full disclosure of images is excellent, you can view a 360 degree video, a normal face-up view, two Ideal Scope Images showing Hearts and Arrows, an Aset Tool image plus the Diamond Report you can view to double check all the angles.
So here it is, the Diamond just evaluated in a normal image, head to WhiteFlash to see the Ideal Scope Images;
1.456 ct F VVS1 A CUT ABOVE® Hearts and Arrows Diamond
Using these images for Symmetry Evaluation;
Symmetry is vital in having an Ideal Cut Diamond, there are thousands of vendors selling , ‘Hearts and Arrows’ branded diamonds. How do you sift through all of this? well it’s nearly impossible. Some retailers say they that their diamond is definately ‘Hearts and Arrows’, but show NO evidence to support this statement.
Using the images supplied, one can visually see slight indiscretions, but I go one step further, see below;
Utilizing Diamond Images to help determine Symmetry
I’ve selected two Round Brilliant Cut Diamonds that are both classed as ‘Ideal Cut’ and the seller states that both are ‘Hearts and Arrows’. On immediate inspection one can see that the Diamond on the right has a couple of symmetry disctretions compared to the one on the left.
I have made up an Angular Grid that I use when looking at buying diamonds online. I call it the , “Angular Grid Overlay Markup” AGOM. It helps me see the actual symmetry of most Diamonds and gemstones. I have overlayed my ‘AGOM’ over the two diamonds. Now it’s even easier to see the symmetry of every Arrow, Star facet or Bezel facet. But this only helps where to look. Looking at an Ideal Scope and even an Aset Tool image gives you even more detail of the facets symmetry without any refractions or reflections in a normal photo.
Here is the Ideal Scope images from both those diamonds with ‘AGOM’. I’ve marked up one of the arrow facets indicated in the ‘possible symmetry discretions’ on both stones. The top arrow on the right Diamond still has some symmetry issues compared to the Diamond on the left. But the bottom arrow pointing at 6 o’clock appears to be quite symmetrical, which is in contrast to what we saw in Image 1. Both Top and Bottom arrows appeared to have issues around the culet point as well as a few others.
So in this instance I would be selecting the one on the left.