LEARN WITH REIKII
Understanding the 4Cs
Cut, color, clarity and carat give us a shared language for describing diamonds. Learn what each grade tells you—and how to use all four together without losing sight of what you genuinely love.
THE BIG PICTURE
The 4Cs Are a Toolkit, Not a Scorecard
A diamond does not need the highest grade in every category to look beautiful. The most satisfying choice usually comes from deciding what you notice first—sparkle, an icy appearance, an eye-clean look, or visual presence—and balancing the remaining grades around that priority.
01 / CUT
The Architecture of Brilliance
Cut describes how effectively a diamond’s proportions, symmetry and polish manage light. A well-cut stone returns more brightness, contrast and flashes of color to the eye. It is different from shape: “round” or “oval” describes the outline, while cut quality describes the craftsmanship of the facets.
- Prioritize balanced proportions and an attractive light pattern over carat weight alone.
- Elongated outlines such as oval, marquise and pear can create a larger face-up impression.
- Step cuts such as emerald and Asscher emphasize broad flashes and clean geometry rather than a splintery sparkle.
02 / COLOR
From Icy White to Warm Character
For white diamonds, color grading describes the absence of visible body color. The commonly used D–Z scale begins with colorless grades and moves toward increasingly warm yellow or brown tones. A difference on paper can be subtle once a stone is viewed face-up in jewelry.
- D–F is considered colorless; G–J is considered near colorless.
- Round brilliants often disguise warmth more readily than elongated or step-cut shapes.
- Yellow and rose gold can make a slightly warmer white diamond feel intentional and harmonious.
- Fancy-color diamonds are judged by hue, tone, saturation and color distribution—not by the D–Z scale.
D–F Near Colorless
G–J Faint
K–M Very Light
N–R Light
S–Z
03 / CLARITY
What You See Matters More Than a Perfect Label
Clarity grades consider internal features called inclusions and surface features called blemishes. Their size, number, position, nature and visibility all contribute to the grade. Many features require magnification to see and have little effect on everyday appearance.
- “Eye-clean” means inclusions are not readily visible without magnification under normal viewing conditions.
- Step cuts have large, open facets and can reveal inclusions more easily than brilliant cuts.
- Inclusions near the edge may be less noticeable once protected by a prong or bezel.
- Review the actual stone whenever possible; two diamonds with the same grade can look different.
Flawless VVS
Very, Very Slight VS
Very Slight SI
Slight I
Included
Illustrative comparison only. Laboratory clarity grading requires controlled conditions and magnification.
04 / CARAT
Weight Is Not the Same as Visible Size
Carat is a measure of weight: one carat equals 200 milligrams. It does not tell you how large a diamond looks from above. Shape, depth and proportions determine how that weight is distributed.
- Compare millimeter dimensions as well as carat weight.
- A deeply cut stone may carry weight below the setting and appear smaller face-up.
- Halo, cluster and three-stone settings can increase overall visual presence.
- Choose the size that feels balanced on your hand and suits how you plan to wear it.
Approximate visual comparison. Face-up dimensions vary by shape and proportions.
THE FIFTH CONSIDERATION
Choose for Character
The 4Cs describe measurable qualities, but they do not describe your taste. Shape, color, setting, metal and the way a stone moves in light all contribute to the feeling of a finished piece.
- Start with your priority. Decide whether sparkle, color, clarity or size matters most to you.
- Set practical ranges. Give yourself flexibility in the qualities you notice less.
- Compare complete pieces. Consider the stone together with its setting and metal.
- Trust your eye. The right choice should feel compelling beyond the certificate.