What are the 4Cs of a diamond and why do they matter?
Colour
Diamonds are colour graded D-Z (alphabetically but with no A, B or C).
The highest grade is ‘D’ which is a colourless Diamond.
Diamond colour is important because the lower grades often look an unpleasant yellowy-brown colour & barely look like a Diamond.
Low colour Diamonds are also worth much less.
Note: Low colour grades are not to be confused with ‘Fancy’ yellow Diamonds. These are very desirable & are a more vivid ‘Canary yellow’ colour.
Clarity
The clarity of a Diamond refers to how obvious the imperfections or ‘inclusions’ are.
Clarity is graded from the perfect ‘Flawless’ or IF (internally flawless). This is where no inclusions are visible through a x10 magnification of a jeweller’s loupe, right down to I3 inclusions which are obvious to the naked eye.
Clarity is important because the more the inclusions there are, the more the light refraction of the Diamond is hindered making it sparkle less.
Low clarity Diamonds are also worth far less than higher clarity grades.
Carat
The carat of a Diamond is simply a weight measurement. 1.00ct = 0.2gms.
For context a 0.50ct round Diamond should measure around 5mm & a 1.00ct more like 6.5mm in diameter. Don’t forget it is a weight measurement so other cuts will vary in size.
It is important to know the precise carat weight of the Diamond you are buying because some weights have a big leap in value. For example, a 0.99ct Diamond is worth much less than a 1.00ct even though they look the same. If a jeweller says ‘Approximately 1.00ct’ it can be very misleading & you could overpay a lot for the Diamond.
Cut
Cut can sometimes refer to the shape of a Diamond but when it comes to Diamond grading it refers to how well the Diamond has been cut & polished from rough.
The cut characteristics are graded form Excellent downwards to Very good, good, fair & poor.
On round Diamonds there should be a grade for ‘Cut’, ‘Polish’ & ‘Symmetry.’ On other shapes of Diamond like Princess cut & Oval there is no cut grade.
