Overview
The 4Cs—Cut, Colour, Clarity, and Carat—define a diamond’s character and price. Beyond these, polish, symmetry, fluorescence and exact proportions also shape how a stone looks in real life. Use the guide below to balance beauty and budget for your perfect diamond.
Cut
Cut quality has the biggest impact on brilliance and fire. For round diamonds, prioritise Excellent/Ideal cut grades with strong symmetry and polish. For fancy shapes (oval, pear, cushion, emerald, princess, marquise), focus on well-balanced proportions and minimal bow‑tie.
Round recommendations
- Table: 54%–58%
- Total depth: 60%–62.5%
- Crown angle: ~34°–35°
- Pavilion angle: ~40.6°–40.9°
- Girdle: Thin–Medium to Slightly Thick
Tip: A well‑cut H–I colour can face up whiter and brighter than a poorly cut higher colour.
Colour
Colour grades run from D (colourless) to Z (tinted). Most buyers find excellent value between G and I for white diamonds; K and below show warmer tones. Metal choice affects perception: yellow/rose gold tolerates slightly lower colour than white metals.
- D–F: Colourless, premium pricing
- G–H: Near colourless, strong value
- I–J: Faint warmth, often great budget pick
Fancy coloured diamonds (yellow, pink, blue, etc.) are graded differently, by hue, tone and saturation rather than the D–Z scale.
Clarity
Clarity reflects the number, size, and visibility of inclusions. “Eye‑clean” (no visible inclusions to the naked eye at normal viewing distance) is the goal for most buyers.
- VS2–SI1: Often eye‑clean depending on stone and shape
- VVS–IF: Extremely clean, premium pricing
- Beware inclusions under the table or black crystals in step‑cuts
Carat
Carat is weight, not size, though face‑up dimensions scale with carat. Prices jump at “magic sizes” (0.90ct, 1.00ct, 1.50ct, 2.00ct). Consider 0.90ct or 1.90ct for better value with similar look to the next threshold.
Polish & Symmetry
These finishing grades affect how cleanly light travels. Aim for Very Good to Excellent for both. Slight variances here can be acceptable if the empirical light return is strong.
Fluorescence
Medium to strong blue fluorescence can make lower colours (I–K) appear slightly whiter. In higher colours (D–F), strong fluorescence may occasionally cause a milky look—evaluate on a case‑by‑case basis.
Proportions
Table, depth, crown and pavilion angles work together to determine brightness, fire and scintillation. Well‑balanced proportions concentrate light back to the viewer rather than leaking it through the sides or bottom.
Certification
Independent grading protects your purchase. We recommend leading laboratories with consistent standards.
- GIA: Considered the industry benchmark for consistency
- IGI: Widely used, strong option especially for lab‑grown diamonds
Verify reports directly with the lab:
Learn more: How to Read a Diamond Certificate
Lab‑grown vs Natural
Lab‑grown
- Chemically and optically identical to natural diamonds
- Exceptional value—larger sizes at a given budget
- Ideal for modern, budget‑savvy buyers
Natural
- Geologically rare, formed over billions of years
- Often stronger long‑term value retention
- Highly regarded for their natural origin
FAQs
What matters most: Cut, Colour, Clarity or Carat?
What is an “eye‑clean” diamond?
Should I avoid fluorescence?
Need Personal Advice?
Speak with our gemologist for tailored recommendations—by message or video.