How to Grade Fancy Cut Diamonds


Gemologists can generally use the same diamond color and clarity grading standards for both rounds and fancies. However, in terms of cut (proportion and finish), fancy cut diamonds differ significantly from standard rounds.

Although the term “fancy” is also used to describe colored diamonds, fancy cut diamonds can be either colorless or fancy colored.

What are the Differences Between Rounds and Fancy Cut Diamonds?

Lapidaries cut fancy shapes to obtain the maximum yield from oddly shaped diamond rough. Although they occur less frequently than octahedrons, many broken pieces of rough are found. In addition, if lapidaries need to cut inclusions of out regular octahedrons, odd shapes may result. Rather than greatly reducing the weight of a finished diamond just to accommodate a round brilliant design, most lapidaries will cut a fancy shape instead.

Faceting Rounds vs Faceting Fancies

In a round diamond, all the facets in a tier are cut to the same angle and depth. Thus, rounds are easier to cut compared to fancy shapes. Whereas automated machines usually cut rounds, fancies must be cut by hand. Since this takes a lot of time, you’ll usually see fancy cut diamonds in larger sizes than rounds.

How Fancy

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Full Article Details


Content Length 2366 words
Reading time 11 min 50 sec

Here's what you get if you unlock this article:

  • What are the Differences Between Rounds and Fancy Cut Diamonds?
    • Faceting Rounds vs Faceting Fancies
    • How Fancy Cuts Affect Brilliance
  • Proportion Analysis for Fancy Cut Diamonds
    • Getting Started
    • Table Percentage
    • Crown Angle
    • Girdle Thickness
    • Pavilion Depth Percentage
      • Face-Up Appearance
      • Total Depth Percentage
      • Crown Height/Pavilion Depth Relationship
      • Bowties
      • Pavilion Bulge
    • Culet Size
  • Finish Analysis for Fancy Cut Diamonds
    • Symmetry Errors
      • Abbreviations for Symmetry Terms
    • Shape Appeal
      • Abbreviations for Shape Appeal Terms
    • Length-to-Width Ratio
    • Polish
  • Clarity Grading Fancy Cut Diamonds
  • Color Grading Fancy Cut Diamonds
  • Notes on Baguettes

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