Cut — the one that matters most
Cut is how well a diamond's facets are angled and proportioned. It decides how much light comes back to your eye as brilliance (white light), fire (flashes of colour) and scintillation (sparkle as it moves).
- Grades for round diamonds run Excellent, Very Good, Good, Fair, Poor (GIA) — IGI uses Ideal and Excellent at the top.
- A well-cut diamond looks brighter and often larger than a poorly cut one of the same weight.
- Polish and symmetry, also on the report, describe finishing quality. Very Good or better is ideal.
Our adviceNever compromise on cut. Choose Excellent or Ideal for round diamonds.
Colour
- DColourless
- FColourless
- HNear colourless
- JNear colourless
- MFaint
- ZLight yellow
Colour grading measures the absence of colour in white diamonds, on a scale from D (colourless) to Z (light yellow or brown).
| Grade | Description | Looks like |
|---|---|---|
| D–F | Colourless | Icy white, even side by side with others |
| G–H | Near colourless | White to the eye once set |
| I–J | Near colourless | Slight warmth, mainly visible from the side |
| K–M | Faint colour | Visible warmth |
D–F
DescriptionColourless
Looks likeIcy white, even side by side with others
G–H
DescriptionNear colourless
Looks likeWhite to the eye once set
I–J
DescriptionNear colourless
Looks likeSlight warmth, mainly visible from the side
K–M
DescriptionFaint colour
Looks likeVisible warmth
Our adviceG–H is the sweet spot in white gold. In yellow or rose gold, the metal warms the stone anyway, so I–J can look just as good for less.
Clarity
- FL / IFNothing at 10×
- VVSPinpoint, very hard to find
- VSMinor, eye-clean
- SINoticeable at 10×
- I1–I3Visible to the eye
Almost every diamond has tiny internal features (inclusions) or surface marks (blemishes). Clarity grades how visible they are under 10× magnification.
| Grade | Meaning |
|---|---|
| FL / IF | Flawless / Internally flawless |
| VVS1 / VVS2 | Very, very slightly included — extremely hard to see even at 10× |
| VS1 / VS2 | Very slightly included — minor, usually invisible to the eye |
| SI1 / SI2 | Slightly included — sometimes visible to the naked eye |
| I1–I3 | Included — visible to the eye |
FL / IF
MeaningFlawless / Internally flawless
VVS1 / VVS2
MeaningVery, very slightly included — extremely hard to see even at 10×
VS1 / VS2
MeaningVery slightly included — minor, usually invisible to the eye
SI1 / SI2
MeaningSlightly included — sometimes visible to the naked eye
I1–I3
MeaningIncluded — visible to the eye
Our adviceYou want an "eye-clean" diamond — no inclusions visible from normal viewing distance. VS2 and many SI1 stones are eye-clean. Step shapes (emerald, Asscher) show more, so choose VS2 or higher for those.
Carat
- 0.50 ct5.1 mm
- 0.75 ct5.8 mm
- 1.00 ct6.4 mm
- 1.50 ct7.3 mm
- 2.00 ct8.1 mm
Carat is weight, not size: 1 carat = 0.2 grams. Two diamonds of the same carat can look different in size depending on cut and shape. Elongated shapes like oval, pear and marquise look larger than a round of the same weight.
Prices jump at "magic" weights — 0.50, 0.75, 1.00, 1.50, 2.00 ct. A 0.95 ct diamond looks the same as a 1.00 ct but can cost noticeably less.
Try our Diamond Size Visualizer to see sizes on a hand.
How to balance the 4Cs
- Cut first — Excellent or Ideal.
- Then carat — the size you want, just under a magic weight if you can.
- Then colour — G–H in white metal, I–J in yellow or rose.
- Then clarity — eye-clean is enough; VS2–SI1 gives the best value.
Beyond the 4Cs: certification
The 4Cs only mean something if an independent lab graded them. Every Candor diamond comes with a GIA or IGI report you can verify online.