The Kaedesigns Diamond Guide
The 4Cs of Diamonds
A practical guide to diamond quality.
Learn what cut, colour, clarity and carat tell you about a diamond, and how to compare them when choosing a stone.
Explore the 4CsCut
The craft behind the sparkle.
Cut is the quality of a diamond’s proportions and finish. Its facet angles, polish and symmetry influence how light behaves inside the stone.
Cut quality and shape are different. Round, oval and emerald describe a diamond’s outline or cutting style; cut quality describes its craftsmanship and appearance.
Shallow Proportions
Light can escape through the pavilion.
Balanced Proportions
Light returns towards the viewer.
Deep Proportions
Light can escape through the sides.
Brightness
Reflections of white light.
Fire
Flashes of spectral colour.
Scintillation
Sparkle and contrast as the diamond, light or viewer moves.
The GIA Cut Scale
- Excellent
- Very Good
- Good
- Fair
- Poor
GIA’s overall cut grade applies to standard round brilliant diamonds in the D–Z colour range. For other shapes, examine the proportions, finish and visual appearance rather than expecting the same cut grade.
Colour
From colourless to a warmer glow.
For diamonds in the normal colour range, colour grading describes how much body colour is present. The D–Z scale runs from colourless towards increasing yellow or brown tint.
Differences between nearby grades can be subtle. Laboratories compare diamonds with masterstones under controlled lighting; a screen cannot establish a colour grade.
Clarity
Small details. A closer look.
Clarity describes a diamond’s internal inclusions and surface blemishes. Graders assess their size, number, position, nature and visibility under 10× magnification.
Inclusions
Features inside the diamond; some may reach its surface.
Blemishes
Features on the diamond’s surface.
The 11 GIA Clarity Grades
Flawless
No inclusions or blemishes visible to a skilled grader at 10×.
Internally Flawless
No inclusions visible at 10×; surface blemishes may be present.
Very, Very Slightly Included
Inclusions are very difficult for a skilled grader to see at 10×.
Very Slightly Included
Minor inclusions, ranging from difficult to somewhat easy to see at 10×.
Slightly Included
Inclusions are noticeable to a skilled grader at 10×.
Included
Inclusions are obvious at 10× and may affect transparency and brilliance.
Carat
Weight, with a different perspective.
Carat measures weight, not diameter. One metric carat equals 0.2 grams and is divided into 100 points. A 0.50 ct diamond is a 50-point diamond.
Compare Carat Weights
Two diamonds of the same weight can look different in size because of their shape and proportions. Check the measurements on the grading report as well as the carat weight.
This illustration compares how large stones look from above when they have the same shape and proportions. It is not to scale, and individual diamond measurements vary.
Your Diamond
Choose the balance that suits you.
The four grades work together. Use them to build a shortlist, then compare the diamonds themselves.
- 01
Start With The Look You Love
Choose a shape and consider how it works with your setting. Compare movement and light, as well as still photographs.
- 02
Compare Like With Like
Read the grading report and compare weight, measurements and quality together. A higher number or grade in one area does not describe the whole diamond.
- 03
Make Room For Your Priorities
Decide what matters most to you: appearance, a particular size, or a particular grade. Bring your shortlist and budget to our jewellers for a closer look.
Read the report. Then look at the diamond.
Check the issuing laboratory, report number, measurements, weight and grading details. Confirm whether the stone is natural or laboratory-grown, and read any treatment information. Reporting formats and terminology can differ between laboratories and diamond types.
A few things worth knowing.
Is cut the same as shape?
Shape describes the outline, such as round, oval or pear. Cut quality considers how the facets and proportions work together. Two diamonds of the same shape can have very different appearances.
Does a higher carat weight always mean a better diamond?
Carat is a weight measurement. Cut, colour, clarity and proportions also matter, so a heavier diamond is not automatically the better choice for your preferences.
Does a clarity grade guarantee that a diamond is eye-clean?
No. Clarity grades are assessed under magnification. Whether you notice an inclusion without magnification depends on the individual stone and viewing conditions.
Can I choose a diamond from the grading report alone?
A report is an important comparison tool, but it does not show everything about appearance. Check the measurements and review any images or video. Examine the stone in person if possible, and ask a jeweller about anything you are unsure of.
Your Next Chapter
Find a diamond. Make it yours.
Explore the diamond collection, or speak with Kaedesigns about a stone and setting that feel right for you.