Hearts and Arrows Diamond Education and Information

Before we begin, let us use the following definition: A diamond is a crystal, a prism that reflects light and disperses it. In other words this prism's facets are two way mirrors that: 1. Reflect light or 2. Allow light to pass through them.
True Hearts found in A CUT ABOVE hearts and arrow diamonds photgraphed in 1999 by Brian Gavin True Hearts found in A CUT ABOVE hearts and arrow diamonds photgraphed in 1999 by Brian Gavin

Because of diamond's refractive index, the pavilion (bottom of the diamond that comes to a point) needs to be cut at an exacting angle. If there is some slight deviation from this angle, the diamond begins to leak light and this affects the light return. The relationship between the crown and pavilion is also very important. We will see this in detail later. The Heart and Arrow pattern is analogous to all round stones, but if the diamonds have not been polished with super symmetry and well within the ideal parameters according to AGS standards, they will not be correctly defined. In addition, they take on a different form, shape and size. Just because a diamond is cut to ideal proportions with an AGS0 does not mean that it will exhibit a crisp and true hearts and arrows pattern. In addition to being ideal, the diamond has to have super symmetry – where all the angles and facets have to be perfect. Stones that do not conform to these standards cannot be called TRUE Hearts and Arrows. There should be no variation in both the hearts and the arrow patterns. Quality A, B, C or 1, 2, 3 do not exist. They are either TRUE Hearts and Arrows diamonds or they are NOT. These standards need to be maintained just as they have in Japan where the standard was set and I believe all should maintain. Today Sarin, Helium and Ogi instruments are used to read and analyze measurements, angles and percentages. This is not a method to indicate the perfection of cutting. These machines show the perfection of the engineering in the equipment and the maintenance of the equipment. Today's cutting equipment is a lot more exacting. What is more important is that the equipment is in good condition and that the cutting plate skyf (pronounced skife like knife) and tang (tool to hold the diamond) are true and level (Fig.1b) with each other so that there is very little deviation in the measurements when the stone is completed. The larger the stone the more visible this deviation can possibly be. Note in (Fig's.1a 1c) that the cutter can dial in the angle for the main pavilion or crown angles for the process of blocking out the stone in 8 cut. As you can see this is not entirely up to the cutter but also the engineers from the maintenance dept.
The precision of the cutter is really seen in the brillanteering (polishing on the lower and upper girdle facets as well as the stars) of the stone. This is where the craft comes into today's diamond cutting world, the finishing of the stone the upper and lower girdle facets (half's) and the stars. It is here where we have to rely entirely on the cutter for his mastery. The Sarin,Helium and Megascopes do measure all these other angles the precision an consistency of these angles reveal how great the cutter is. One method which reveals this all is by looking through the H&A scope at the hearts, one can see the precision and consistency of the cutting. The antithesis of this is when a master diamond cutter swindles a stone, meaning he recovers the maximum possible weight and makes a lively stone. The angles; measurements and percentages will deviate by much on this stone, compared to a superideal. The Sarin,Helium and Megascope machines will not show this mastery in the cutting but deviation yes. This machinery dose not prove how perfectly the stone has been cut. There is still one simple method above all the sophisticated MACHINERY and that’s the heart and arrow scope. If the machinery were to measure no deviation in other words if each angle was exactly the same one would view a diamond that would look dull to the eye much like a tympani drum, if one plays it in the center the sound is not good at all compared to when it is beat off to the side. We found a careful balance must be maintained between
  • Angles (balance between Crown and Pavilion)
  • Consistency of Heart pattern (super symmetry also known as optical symmetry)
  • Symmetry (external meet point symmetry)
  • Excellent or Ideal polish with very good luster
I believe this is what I set out to achieve when we produced the first A CUT ABOVE diamond in late 1997.