The Essential 4C's
Hearts & Arrows Diamonds
During the 1980s in Japan, it was discovered that when a round brilliant diamond with exceptional symmetry was viewed from the bottom through a special viewer a pattern of hearts could be seen, and when viewed from the top showed eight gray arrowheads. Diamonds displaying such exceptional symmetry account for less than 1 % of all diamonds cut. The highest grades of polish, symmetry and perfect cutting angles allow it to reflect more light than a standard cut diamond.
Following the discovery, a special viewer was developed to display the Hearts & Arrows effect. The viewer is useful in determining the optical symmetry of a diamond, through the internal movement of light and reflection, depending on the size, shape and arrangement of facets. This optical symmetry is different from the Symmetry Grading on a laboratory grading report that assesses the ‘tidiness’ of facet intersections and placement. Diamonds with Hearts and Arrows patterns became very popular in Japan and spread as a trend in the USA during the mid 1990s.
The hearts and arrows pattern is now so popular that many diamond manufactures cut to a specification that will yield this particular pattern, even at the expense of overall cut quality.
The intrinsic appeal of the hearts and arrows pattern, with its association to Cupid, is obvious; even if the heart pattern is invisible once the diamond is set. Often the presence of the hearts and arrows pattern is taken as confirmation that the diamond is well cut. This is not necessarily true. In a round diamond, a clearly defined set of 8 hearts and 8 arrows is a sign of excellent optical symmetry, an important component of cut. As such, its appearance is very likely a sign of superior cut, but not a guarantee.
Consumers are often misled regarding the quality of a hearts and arrows pattern. While a diamond may display what appears to be a pronounced hearts and arrows effect, several subtle details in the shape, spacing, and positioning of the pattern can have a significant impact on desirability and therefore value. These variations are often not detectable by any except experienced graders or jewelers.
Even so, the marketing impact of the hearts and arrows campaign has been profound. Because well cut diamonds are rare to begin with, and diamonds with the particular hearts and arrow pattern rarer still, H&A diamonds carry a premium price. This is due not only to effective marketing, but because all well cut diamonds (including H&A) require more time to cut, and generate about 15% more waste than lower quality cuts.
For consumers, the greatest benefit of the popularity of hearts and arrows is actually the increased attention brought to the grading of cut. In the late 90s, major labs (including GIA) quickly perceived the demand for a cut grade by customers newly educated to the importance of cut and symmetry in the overall appearance of a diamond. Today, independent laboratory cut grades are the single biggest factor in helping customers to distinguish quality (beyond colour and clarity) in diamonds.