Diamond Cut
Traditional principles guide the artistry of gem-cutters, including formulas for facet
number/placement/proportions for each standard diamond shape (round, princess, ideal,
marquis, oval, emerald, etc.) These proportions – especially a gemstone’s depth relative
to its diameter – have evolved to maximize brilliance and fire of any given diamond. A
grading standard for diamond cut is founded on measures how effectively the gemstone
reflects the light that enters it, generating a spectrum of colors.
The proportions of a well-
cut diamond permit it evenly to reflect and refract a burst of that
light and color back to the eye. Diamonds carry grades from Excellent down to Poor:
Excellent: (
Top 1%), reflecting virtually all light that enters the gemstone
Ideal: (
Top 3%), reflecting almost all the light that enters the gemstone
Very Good: (
Top 15%), reflects almost as much light as “Ideal” stones at lower price
Good: (
Top 15%), reflects most of the light that enters the gemstone, at cost considerably
lower than “Very Good”
Fair: (
Top 35%), less brilliant (also less expensive) than gemstones graded “Good”
Poor: All other diamonds below the “Fair” grade.
Shapes
The most important criterion for many diamond clients, however, is shape. No one shape
is “best,” or better than any other. It’s purely a matter of personal preference. Here are
the most popular shapes available in the diamond market today:
