Hearts and arrows
From Wikipedia, the free encyclopedia
Hearts and arrows (H&A) is a cutting style for round brilliant diamonds modelled after a pattern popularized by the EightStar Diamond Company. Looking at the pattern is also a way of measuring optical symmetry, while gem labs only measure physical symmetry.
The value of a diamond is determined by four factors known as the "Four Cs": Cut, Colour, Clarity and Carat. Carat refers to the stone's weight, clarity grades the degree of impurities contained in the stone, and colour defines the shade of the stone, from the purest white to a yellowish tone. Cut is the way in which the rough stone has been fashioned into a gem. Most gemologists consider cut the most important diamond characteristic because it has the largest impact on a diamond's brilliance.[1] Even if a diamond has perfect color and clarity, a diamond with a poor cut will have dulled brilliance.[2] A very well cut diamond can mask clarity inclusions and make a diamond appear more colorless as well. [3]
The hearts and arrows pattern appears in brilliant-cut diamonds that have very good parallelism and symmetry. The pattern is a series of eight gray arrowheads when viewed from above the "crown" with one eye and eight heart shapes when viewed from below the "pavilion". H&A viewers eliminate incoming light from certain angles and cause the pattern to appear black or very dark gray. In order to display this pattern flawlessly, the diamond's top facet or "table facet" must be exactly perpendicular to the bottom of the diamond or "pavilion". It must also be cut to have great symmetry of its major facets and have particular lengths of its lower girdle facets.
Diamonds with a H&A cut command a price premium in the US market, reflecting the generally greater time needed to produce them and the greater loss of weight from rough, as well as their generally better overall cut quality.[4] It has also become a popular sales tool in diamond marketing. Although the hearts and arrows property is indicative of a top-tier cut, it does not always mean the diamond will be the most brilliant. Optimal facet placement is the key to brilliance and more important than facet patterning. Some people may dislike the hearts and arrows patterning as well, since they may see dark arrow-shaped shadows in their diamond under certain lighting conditions.
While the major facets must be very symmetrical, there is considerable room for variation in cut quality and appearance from the "minor" facets, and from the angles of the major facets.
[edit] H & A Labelling
Some in the diamond industry disagree on which diamonds should receive the "Hearts and Arrows" label. Because there is no industry standard, one person or company may say a diamond is a "Hearts and Arrows Diamond" while another may say it is not.[5] Most diamonds with an overall cut graded by GIA as "Excellent" (with Excellent symmetry as well) or AGS as "0" (or "Ideal") will have some sort of hearts and arrows pattern when seen through a viewer, although the pattern may not be perfect. Some in the diamond industry believe the hearts and arrows pattern should be graded, and only those with the top grade should be called "Hearts and Arrows."[6] [7] Those people believe just the presence of a hearts and arrows pattern alone is not enough to be considered a hearts and arrows diamond, the pattern must be perfect to within certain guidelines. One company's guidelines for the splits on hearts are as follows: "Check if the hearts are split, measure length of heart then the length of the split. Calculate the % of the length split, if it is greater than 8% and there are more than 2 of then it fails.[8]" The guidelines may vary depending on what benefits which company.
[edit] History
The timeline of the evolution of Hearts and Arrows is:
- 1977-1984 Ken Shigetomi et al perform research to develop the FireScope.
- Kazumi Okuda contracted by Ken Shigetomi develops a tool based upon Shigetomi's research to help examine diamond cut, this device eventually becomes the FireScope.
- 1985 First EightStar diamond cut by Higuchi for Takanori Tamura in Tokyo after research using the Firescope and a worldwide search to find diamonds which gave a perfect result in it found almost none out of tens of thousands examined.
- 1987 First "copy" of EightStar by Ken Shigetomi of Tokyo, called Apollon 8.
Shigetomi's company fails because of quality control problems.
- 1988 Kinsaku Yamashita, A salesman for Apollon 8 buys the remaining Apollon 8 diamonds, develops relationships with the Apollon 8 subcontractors and renames the cuts Hearts and Arrows. Kinsaku Yamashita also patents the Heart and Arrow viewer and copyrights the words Heart and Arrow.
- 1990 EightStar Diamond Company USA founded, initially as offshore cutting operation for the Japanese company
- 1997 Hearts on Fire brands in the US and is the first hearts and arrows diamond to be sold in retail stores.
- 1997 A Cut Above brands in the US and is the first hearts and arrows diamond to be sold exclusively on the internet.
- 2005 The Solasfera diamond in the US, is first to cut a diamond with "10" perfect hearts and arrows.
The different cuts each have somewhat different appearances and balance of features and aren't complete, literal copies of the EightStar cut. Some exhibit much better results.
