Tutorial : Precision
All diamonds look nice under bright lights, but most become noticeably average in normal conditions. Those which continue to sparkle and dance have good cut quality. Cut quality can be separated into two distinct areas:
How do Optical Symmetry and Hearts & Arrows Viewers work?
The diamond is set face-down to see pavilion cut precision. It is turned over, face-up, to see crown cut precision. When the viewer is placed over the diamond light from above is coded white and light from the sides is coded red (other colors may be used).
The Round Brilliant is the only shape with a global nickname for cut precision (“Hearts & Arrows”). The reason for this is obvious when looking through an optical symmetry viewer.
Different Shapes have Different Standards
Fancy cuts are not held to the same standards as Round Brilliants. The crisp uniformity of patterns seen in precisely cut rounds is not possible with more complex facet arrangements. As a result shapes other than round are practically never discussed in terms of cut precision. However, as the benefits of cut precision are studied by research labs and made known to consumers we are confident cut-focused manufacturers will begin to pay attention to their development.
Depending on configuration, a princess cut will have between 24-48 facets on its pavilion and 17-29 cut on the crown. This makes for a wide variety of looks even when the patterns are readable. The princess cut below has a 24 facet pavilion (known as “2-chevron”).
While the colors do not indicate levels of light return (AGS ASET® and Ideal-Scope® can be used for this) they show how well a diamond’s facets align with each other in 3D. Where other viewers focus only on the crown view, the optical symmetry viewer shows both crown (top) and pavilion (bottom) views.
Benefits of Cut Precision
Cut Precision fine-tunes diamonds which already enjoy top performance. The better-defined contrast pattern creates sharper on-off scintillation and more primary colors in dispersion (less pastels and earth tones). Precision cutting maximizes the return of all available light, even in softer lighting conditions. This is a logical result of all of the facets, the tiny mirrors inside the diamond, brought into precise alignment with each other. Face up color is also improved when light gets in and out of a diamond with more intensity. This can be noted in many diamonds with above-average performance. High performance coupled with top cut precision enhances the effect even more.
Why aren’t more diamonds cut like this?
A high level of micro-precision takes modern tools and more time to achieve. It also requires polishing away more carat weight. Assembly-line factories with dated equipment would have to sacrifice more time and produce smaller diamonds to do this, costing millions in time and carat weight.
Cut Performance should be a prerequisite for Cut Precision. Understanding that, diamonds which enjoy high performance and precision are dizzying, dazzling and rare treasures to behold.
Copyright 2010 Continental Diamond