Intermediate Hearts and Arrows

Do they cost more to produce?

Yes, primarily due to weight loss incurred in refinement. Achieving strong hearts and arrows optical precision is an exacting process. All facets must be aligned in both angle and orientation in a three-dimensional way.

The three examples below are hypothetically polished from the same starting rough crystal (the dark blue outline). They would all receive the “Excellent” cut grade. The specimen which meets PriceScope’s definition of Super Ideal cost more to produce because it required more hours, better tools and, most notably, more weight loss from the original diamond crystal.

PriceScope Round Diamond Subsets

The payoff is the potential to optimize light performance through cut-consistency: Top brightness can be achieved by cutting to angles which promote optimum light return. Optimizing the size of the diamond’s internal reflections, or compound mirrors, promotes wider bands of dispersion, which our eyes see as fire.

What laboratories grade H&A diamonds?

The top-tier laboratories which apply grading standards for the hearts and arrows diamond are IGI and GCAL.

• • IGI is highly regarded for their hearts and arrows diamond grading across China and India.
  • GCAL is best known for high-quality, standardized images and videography.

Beware hearts and arrows laser inscriptions

When submitting a diamond, the producer can request for anything to be inscribed on that diamond. For example, the producer could ask for “D-Flawless” to be inscribed on a J-SI1 diamond and that inscription would then become listed in the comments section. Therefore, when you see the notation that a diamond has “Hearts and Arrows” or “H&A” inscribed on its girdle issued by a laboratory that does not grade hearts and arrows, be cautious. Such an inscription does not mean a hearts and arrows standard was passed. It only means the producer requested for those characters to be inscribed when the diamond was submitted to the lab.

Hearts and Arrows Doesn’t mean Top Light Performance

Because of a diamond’s refractive index, the pavilion and crown need to be cut at angles that complement each other and return light to the viewers’ eyes. No matter how crisp the hearts and arrows optical precision maybe, if the primary angles don’t compliment each other the diamond begins to leak light, which affects light return. Hearts and arrows diamonds need separate assessment for light return. A hearts and arrows viewer doesn’t give any indication of light performance.

AGS Ideal does not mean Hearts and Arrows

Just because a diamond is cut to have AGS ideal performance does not mean that it will exhibit a crisp hearts and arrows pattern. Here is an example of a diamond that has AGS Ideal Light Performance, but would be completely unacceptable by any meaningful hearts and arrows standard:

Symmetry is not H&A Optical Precision

Be advised that the symmetry grade, found on every diamond grading report, is not an assessment of optical precision. It is completely blind to how internal facet reflections may or may not overlap to form H&A patterns.

• Both diamonds were photographed using a hearts & arrows viewer.
• Both received the top lab grade (Excellent/Ideal) in symmetry.

The difference in facet relationships is obvious, but on paper the symmetry grade is the same. This is how H&A patterning – resulting from optical precision – is not the same thing as lab graded symmetry.

A laboratory symmetry grade largely involves 2D surface judgments about uniform facet shape, clean meet points and overall geometry. The formation of hearts and arrows involves polishing on the X,Y, and Z-axes, which is not assessed as any part of laboratory symmetry grading.

GIA has concluded that there is negligible visible difference between VG and EX in symmetry and polish. They did find naked eyed experts who could sometimes detect lower symmetry in diamonds receiving Good or lower.

GIA and AGS do not grade Hearts and Arrows

Since GIA and AGS do not currently grade hearts and arrows, the assessment of hearts and arrows quality in a GIA or AGS graded diamond requires separate analysis of that diamond’s 3D optical precision.

Analyzing H&A diamonds

If you can’t examine the diamond in a hearts and arrows viewer yourself, then hearts and arrows photos made with a camera looking into the viewer are the best way to judge the degree of precision and accuracy to which the optical precision was executed.

Hearts and Arrows Photos

PriceScope vendors specializing in hearts and arrows diamond reliably provide actual hearts and arrows photos for diamonds they sell.

Computer Generated Images (CGI)

Some diamond industry software applications such as DiamCalc and the AGS light performance software are capable of generating photorealistic diamond images and videos. These computer generated renderings include performance scope (i.e. Ideal-Scope, ASET) simulations and optical precision scope (i.e. Hearts and Arrows) simulations.

The easiest way to produce computer-generated images (CGI) is to manually enter data from a grading report into the software. This is not useful and is misleading. When only broad average numbers are entered the software draws perfect 3D optical precision (which doesn’t exist in nature) and will produce images based on a theoretically perfect, unrealistic diamond wireframe.

The perfect optical patterns circled below are misrepresentations. It’s impossible to know how close or far away from the actual diamond’s hearts and arrows patterns these CGI may be. The data on laboratory reports is also averaged and rounded, adding a further margin of error.

Images rendered from a 3D Scan (an actual mechanical scan of the diamond)

The only representative CGI are those made from a mechanical 3D scan of the actual diamond, executed with a non-contact diamond scanner such as Sarine or OGI. The hearts and arrows images generated by the software may be very close to actual hearts and arrows photos, depending on whether the scan was well-executed or not. They are still not as decisive as actual photos or in-person viewing for nuanced analysis.

Because computer-generated images have the appearance of actual photos, it is important to verify with the seller if the imagery they are providing is actual photography of the diamond, or CGI. If the images are CGI, verify that the seller secured a mechanical 3D scan of the actual diamond.

AGS Light Performance Maps

AGS Platinum Reports may have diamond specific renderings of ASET maps. When these are printed on “dual light map” or “triple light map” certificates, as seen below, an ASET image is rendered for the bottom of the diamond. The only purpose of that rendering is to simulate the hearts pattern in order to communicate 3D optical precision. Because these images are made from an actual 3D scan they can be very representative. They are not as decisive as actual photos or in-person viewing.

Advanced Hearts and Arrows Diamond

History and Symbolism

In the 1980s, Japanese diamond cutters were first to produce round brilliant diamonds cut so precisely that their facet reflections overlapped in 3D space, creating consistently-shaped patterns when seen through reflecting viewers.

Those polishers used “secret recipes” to create the pattern of hearts – a combination of reflections circled in red below – when looking down on the pavilion and arrows – reflections of the eight pavilion-main facets seen through table and bezels – in the crown, when viewed in the table-up position.

The precision and crispness of the patterns relies on precise angles in combination with specific facet length, width and azimuth. The techniques of the first producers spread to other cutting houses and hearts and arrows diamonds began appearing on several continents by the mid-1990s.

Symbolism

The eight uniform patterns seen in the top and bottom of hearts and arrows diamonds have a historical association with good fortune and spiritualism. The number eight is considered lucky in Asian culture. The arrow pattern has been compared to the Octagram of the I Ching, the Rinbo of Buddhist law and the eight-spoked wheel of Dharma, associated with spiritual perfection in the Buddhist faith.

Regardless of spiritual belief, the achievement of the perfect hearts and arrows pattern, painstakingly cut into the world’s hardest substance, can be appreciated by any admirer. In its most fundamental form, it symbolizes the diamond cutter’s quest for perfection and the ultimate beauty of a diamond.

H&A Cutting Process

Our thanks to Whiteflash for providing the graphics and images below.

Sawing

The rough diamond is prepared and sawed. Depending on the grain of the rough, this can happen in different ways. The flat, sawed surface will ultimately become the diamond’s table. The stone is then “bruted” or girdled (made round).

Blocking

Next, the stone is “blocked:” first in four, then in eight.  Four facets are polished on the top, forming the first crown main facets, next to the flat table facet.

Four main facets are also polished on the bottom, forming the first pavilion main facets. These ideally come to an exact point. The stone is now blocked in four.

The remaining facets are then polished on the top, for a total of eight main crown facets adjacent to the table, as well as the bottom, for a total of eight main pavilion facets. With these primary 17 facets in place (1 table facet, 8 crown facets and 8 pavilion facets) the diamond is now blocked in eight.

Brillianteering

With the main facets in place, the upper and lower halves and stars are polished on the stone.

How the Hearts and Arrows are Formed

Here is a view of how the hearts and arrows are formed during the cutting process, seen through a hearts and arrows diamond viewer.

Hearts Formation

1. The main pavilion facets are outlined and one heart is highlighted in red.
2. The main pavilion facet reflects on the opposite side.
3. It takes a total of six facets to create one heart: Four facets create the main body (and one arrowhead on the pavilion) and an additional two upper half facets finish up and square off the tips of the “rabbit ears” of the heart.
4. Figure A shows the heart formed only by the four main facets, without the upper half facets in place. Figure B shows the complete heart, with the two upper girdle facets in place. Note the squared-off heart shape.

Arrows Formation

Just as the main pavilion facets are responsible for the formation of the hearts, they are also key in forming the arrows pattern: The shaft of the arrow is formed when one main pavilion facet reflects on the opposite main pavilion facet. The main crown facet allows a different view of the reflected main pavilion facet thereby forming the arrowhead.

Grading Guidelines

There are different approaches to the assessment of hearts and arrows optical precision. The long-standing guidelines below were developed and carried forward by hearts and arrows subject-matter experts and have proven popular among enthusiasts in the PriceScope community.

Grading hearts and arrows requires in-person viewing. Confirmation of quality is practical with high quality photos made in a hearts and arrows viewer. CGI cannot be used for meaningful hearts and arrows assessment.

Grading the Hearts

• Eight equal uniformed symmetrical hearts.
• Eight distinct symmetrical hearts separate from the arrowheads above. If this is correct, check the following.
• Check if the hearts are split and measure the length of the heart, then the length of the split.
• Calculate the % of the length split – if it is greater than 8% and there are more than two of them, it’s not a classic heart shape.

Detail

First: Check to have eight equal hearts and arrow heads. They must be equal in size and shape, as seen in the “Acceptable” picture below. In the “Fails” picture, you can see the hearts are not equal in size and there is an unacceptable split length in the cleft.

In A1, A2, and A3 the heart is well-defined; the gaps between the arrowheads are distinct and clear, and the split at A3 is minimal versus F1, F2, and especially F3.

Next: Calculating whether cleft splits are acceptable, you can measure heart-length as shown X to Y in figure 1a. Any splits in the cleft can be no longer than 8% of that calculated heart-length. In addition, the point of the heart must separate from the chevron above, as seen near the Xs.

Unacceptable Examples

Here are examples of hearts that are not acceptable, simply because they are not equal and homogenous, and the arrowhead and hearts blend together in some cases.

Grading The Arrows

• Each arrow must be clearly visible with a shaft and an arrowhead.
• The eight arrows shafts, as well as heads, have to be straight and in the right position.
• The eight arrow points must meet the girdle.
• There must be total uniformity and balance.

At a casual glance, the poorly-formed arrows are not immediately seen as unacceptable. Look closely: not all the arrowheads reach the girdle and the shafts do not line up straight with the arrowhead.