Lab Diamond 4Cs Guide: Color, Clarity, Cut and Carat Explained
The four grades that decide how a diamond looks and what it is worth, and the order to prioritise them when you buy.
The author is the founder of Draco Diamond. Grading scales described here are the standard gemological scales used on IGI reports. Every Draco piece is IGI certified, E to F color, VS2 clarity or better, and verifiable at IGI.org.
The color scale, D to Z
D is completely colorless; color increases toward Z. Draco stones sit at E to F, inside the colorless range.
Source: standard gemological color scale, graded on IGI reports. The scale runs D to Z.
What is cut, and why does it matter most?
Cut is the grade that measures how well a diamond's facets are proportioned and finished, and it is the one that does the most for how the stone looks. Cut controls brilliance, the white light that returns to the eye, and the fire and sparkle that make a diamond come alive. A diamond is graded on a scale from Excellent to Very Good, Good, Fair, and Poor. An Excellent or Very Good cut returns the most light; a weaker cut leaks light through the bottom and looks dull even at high color and clarity. This is why cut is the first C to protect: it decides whether the other three are working for you.
Cut also drives apparent size. A well cut stone reflects light across its whole face and reads larger and brighter, while a poorly cut stone of the same carat looks smaller and lifeless. The IGI report grades cut on the round brilliant and records the proportions behind that grade, so you can confirm the quality rather than take it on trust.
"Cut is the C you feel before you read the report. It is the difference between a diamond that returns light and one that simply sits there."
Garrett McMartin, Founder, Draco Diamond
What color should you choose?
Color grades how colorless a diamond is, on a scale from D to Z. D is completely colorless and the scale moves toward Z, where a faint to light yellow tint becomes visible. The ranges that matter for buyers are simple: D to F read colorless, and G to J read near colorless, where a faint warmth is hard to detect once the stone is set. Draco stones are graded E to F, inside the colorless range, so the diamond looks white against the metal without paying for the very top of the scale.
| Grade | Range | How it reads |
|---|---|---|
| D, E, F | Colorless | No visible color; Draco is E to F |
| G, H, I, J | Near colorless | Faint warmth, hard to detect when set |
| K to M | Faint tint | Slight yellow visible face-up |
| N to Z | Light tint | Noticeable yellow tone |
What clarity is eye clean?
Clarity grades the tiny natural inclusions inside a diamond and any marks on its surface. The scale runs from Flawless (FL) and Internally Flawless (IF) at the top, through VVS1 and VVS2 (very very slightly included), VS1 and VS2 (very slightly included), SI1 and SI2 (slightly included), down to I1, I2, and I3 (included). The grade that matters most to buyers is eye clean: a stone where inclusions are not visible to the unaided eye, face-up, at a normal viewing distance. From VS2 upward, a diamond is reliably eye clean, which is why Draco stones are graded VS2 or better. You get a clean look without paying for flawless grades the eye cannot tell apart once the stone is set.
| Grade | Meaning | Eye clean? |
|---|---|---|
| FL, IF | Flawless, internally flawless | Yes |
| VVS1, VVS2 | Very very slightly included | Yes |
| VS1, VS2 | Very slightly included | Yes; Draco is VS2 or better |
| SI1, SI2 | Slightly included | Sometimes |
| I1, I2, I3 | Included | Often visible |
What does carat measure?
Carat measures a diamond's weight, not its size. Because a diamond is three dimensional, weight grows faster than the width the eye reads, so doubling the carat does not double the look. Carat is the C to pair with cut: a well cut stone spreads light across its whole face and reads larger than its weight suggests, while a poorly cut heavier stone can look smaller and duller. With lab grown pricing low, carat is usually the C you set to budget last, after cut, clarity, and color are locked. For how each carat reads on the hand, see the carat size comparison.
How should you prioritise the 4Cs?
The four grades interact, so the order you spend in decides the result. Prioritise cut first, because it drives the sparkle that makes a diamond beautiful and reads as size. Next, choose VS2 clarity or better so the stone is eye clean, with no inclusions visible to the unaided eye. Then pick E to F color for a colorless look against the metal. Finally, set carat to your budget, because once cut, clarity, and color are right, weight is the lever you can move without hurting how the stone looks. This is exactly how Draco grades every stone: cut protected, VS2 or better, E to F color, IGI certified.
| Priority | C | Target |
|---|---|---|
| 1 | Cut | Excellent or Very Good |
| 2 | Clarity | VS2 or better, eye clean |
| 3 | Color | E to F, colorless |
| 4 | Carat | Set to budget |
Every grade above is recorded on the IGI report, which you can verify free at IGI.org. To learn how to read each line on the certificate, see the IGI certificate guide. To pair a cut, color, clarity, and carat and see the price before you commit, use the ring builder or browse women's rings.
How to read the 4Cs on a report
An IGI report records all four grades in one place. Read them in priority order. First find the cut grade and confirm it is Excellent or Very Good. Next read the clarity grade and confirm it is VS2 or better for an eye clean stone. Then read the color grade and confirm it sits in E to F. Last, read the carat weight. Finally, take the report number and verify it free at IGI.org to confirm the stone matches the grades printed on the certificate.
Lab diamond 4Cs FAQ
What are the 4Cs of a diamond?
The 4Cs are cut, color, clarity, and carat. Cut grades how well the facets return light and matters most for sparkle. Color grades how colorless the stone is on a D to Z scale. Clarity grades internal inclusions and surface marks. Carat measures weight. All four are recorded on an IGI report and verifiable at IGI.org.
What color lab diamond should I buy?
Choose E to F for a colorless look, or G to J for near colorless where a faint warmth is hard to detect once set. D to F read colorless; G to J read near colorless. Draco grades every stone at E to F, inside the colorless range, so the diamond reads white against the metal.
What clarity is eye clean?
Eye clean means no inclusions are visible to the unaided eye, face-up, at a normal viewing distance. From VS2 upward a diamond is reliably eye clean, which is why Draco stones are graded VS2 or better. Grades above VS2, such as VVS and Flawless, are also eye clean but look the same to the unaided eye once set.
What does VS2 mean?
VS2 stands for very slightly included, grade two. It sits just below VS1 and above SI1 on the clarity scale. A VS2 stone has minor inclusions that are not visible to the unaided eye face-up, so it is eye clean. It is the threshold Draco uses as its minimum, with many stones grading higher.
Which of the 4Cs matters most?
Cut matters most because it drives brilliance, fire, and sparkle, and makes the stone read larger. Prioritise cut first, then VS2 clarity or better for an eye clean stone, then E to F color, and set carat to budget last. A well cut smaller stone outshines a poorly cut larger one.
References
- Standard gemological grading scales for cut, color, and clarity, as graded on IGI reports. Accessed June 2026.
- International Gemological Institute, report verification, IGI.org. Accessed June 2026.
- Draco Diamond grading standard: IGI certified, E to F color, VS2 clarity or better, dracodiamond.com. Accessed June 2026.
Cut first, then the rest
Every Draco piece is IGI certified, E to F color, VS2 clarity or better, in 10K to 18K gold, platinum, or silver. The certificate is included with every order. Free insured worldwide shipping to 25 markets, free resizing, 30 day returns, Lifetime Authenticity Guarantee, signature on delivery.
