Perfect Diamond Cut – for different diamond shapes

The cut is one of the most important aspects when choosing a diamond which is going to look stunning. It is principally the quality of the cut which defines how much sparkle, fire and colour you will get from a diamond.

Even when a jeweller defines the cut of a diamond as ‘Ideal’ it can sometimes be far from it, and for shapes other than a round cut there may be no indication of cut at all, so here is a clear table of what to look for to get the perfect diamond cut for all the most popular diamond shapes.

Depth Percentage – The depth of a stone measured from the table to the culet. It is expressed as a percentage of the stone’s diameter at the girdle.

Table Size – The size of the table of a fashioned diamond is expressed as a percentage of the stone’s narrow-girdle diameter. On a round brilliant, it is measured from corner to opposite corner, rather than from flat side to flat side.

Ratio : Is referred to the overall diamond in LENGTH to WIDTH.

Girdle – The outer edge, or periphery, of a fashioned stone; the portion that is usually grasped by the setting or mounting; the dividing line between the crown and pavilion.

Here’s a few suppliers who provide you with all the necessary information to allow you to fully assess the quality of the diamonds you are considering :-

Blue Nile – USA and UK huge selection     James Allen – High quality site with great graphics

Union Diamond – Large stock and quality site   Diamond Manufacturers – UK site with very keen prices

ROUND BRILLIANT
Excellent Very Good Good Fair / Poor
Depth % 59.0% – 61.0% 58.5% – 58.9% or 61.1% – 62.5% 58.0% – 58.4% or 62.6% – 63.0% Outside the ranges
Table % 52.4% – 57.5 % 57.6% – 59.5% 59.6% – 62.5% Outside the ranges
Ratio 1.00 : 1.00 1.001 – 1.005 : 1.00 1.006 – 1.01 : 1.00 Outside the ranges
Girdle Medium, Facted Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

MARQUISE BRILLIANT
Excellent Very Good Good Fair / Poor
Depth % 56.0% – 72.0% 52.0% – 55.9% or 72.1% – 75.0% 48.0% – 51.9% or 75.1% – 78.0% Outside the ranges
Table % 53.0% – 57.9 % 58.0% – 61.0% 61.1% – 62.5% Outside the ranges
Ratio 1.95 – 2.05 : 1.00 1.80 – 1.94 or 2.06 - 2.10 : 1.00 1.70 – 1.79 or 2.11 - 2.15 :1.00 Outside the ranges
Girdle Medium, Facted Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

OVAL BRILLIANT
Excellent Very Good Good Fair / Poor
Depth % 56.0% – 65.0% 55.0% – 55.9% or 65.1% – 67.5% 54.0% – 54.9% or 67.6% – 70.0% Outside the ranges
Table % 53.0% – 57.9 % 58.0% – 61.0% 61.1% – 62.5% Outside the ranges
Ratio 1.45 – 1.55 : 1.00 1.35 – 1.44 or 1.56 - 1.60 : 1.00 1.30 – 1.34 or 1.61 - 1.65 : 1.00 Outside the ranges
Girdle Medium, Facted Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

PEAR SHAPE
Excellent Very Good Good Fair / Poor
Depth % 56.0% – 65.0% 55.0% – 55.9% or 65.1% – 67.5% 54.0% – 54.9% or 67.6% – 70.0% Outside the ranges
Table % 53.0% – 57.9 % 58.0% – 61.0% 61.1% – 62.5% Outside the ranges
Ratio 1.55 – 1.65 : 1.00 1.45 – 1.54 or 1.66 - 1.70 :1.00 1.35 – 1.44 or 1.71 - 1.75 : 1.00 Outside the ranges
Girdle Medium, Facted Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

HEART SHAPE
Excellent Very Good Good Fair / Poor
Depth % 56.0% – 65.0% 55.0% – 55.9% or 65.1% – 67.5% 54.0% – 54.9% or 67.6% – 70.0% Outside the ranges
Table % 53.0% – 57.9 % 58.0% – 61.0% 61.1% – 62.5% Outside the ranges
Ratio 1.00 – 1.05 : 1.00 1.06 – 1.10 : 1.00 1.11 – 1.20 : 1.00 Outside the ranges
Girdle Medium, Facted Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

RADIANT CUT
Excellent Very Good Good Fair / Poor
Depth % 60.0% – 63.0% 59.0% – 59.9% or 63.1% – 65.0% 58.0% – 58.9% or 65.1% – 70.0% Outside the ranges
Table % 53.0% – 57.9 % 58.0% – 65.0% 65.1% – 75.0% Outside the ranges
Ratio 1.00 – 1.20:1.00 1.21 – 1.25 :1.00 1.26 – 1.35 : 1.00 Outside the ranges
Girdle Medium Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

EMERALD CUT
Excellent Very Good Good Fair / Poor
Depth % 60.0% – 63.0% 59.0% – 59.9% or 63.1% – 65.0% 58.0% – 58.9% or 65.1% – 70.0% Outside the ranges
Table % 53.0% – 57.9 % 58.0% – 65.0% 65.1% – 75.0% Outside the ranges
Ratio 1.35 – 1.55 : 1.00 1.30 – 1.54 or 1.56 - 1.65 : 1.00 1.25 – 1.29 or 1.66 - 1.70 : 1.00 Outside the ranges
Girdle Medium Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

ASSCHER CUT
Excellent Very Good Good Fair / Poor
Depth % 59.0% – 65.0% 58.0% – 58.9% or 65.1% – 67.0% 57.0% – 57.9% or 67.1% – 70.0% Outside the ranges
Table % 53.0% – 57.9 % 58.0% – 65.0% 65.1% – 70.0% Outside the ranges
Ratio 1.00 – 1.05 : 1.00 1.06 – 1.09 : 1.00 1.10 – 1.12 : 1.00 Outside the ranges
Girdle Medium Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

PRINCESS CUT
Excellent Very Good Good Fair / Poor
Depth % 60.0% – 75.0% 59.0% – 59.9% or 75.1% – 77.0% 58.0% – 58.9% or 77.1% – 79.0% Outside the ranges
Table % 53.0% – 57.9 % 58.0% – 65.0% 65.1% – 75.0% Outside the ranges
Ratio 1.00 – 1.05 : 1.00 1.06 – 1.10 : 1.00 1.11 – 1.15 : 1.00 Outside the ranges
Girdle Medium Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

CUSHION SHAPE
Excellent Very Good Good Fair / Poor
Depth % 59.0% – 65.0% 58.0% – 58.9% or 65.1% – 67.0% 57.0% – 57.9% or 67.1% – 70.0% Outside the ranges
Table % 53.0% – 57.9 % 58.0% – 65.0% 65.1% – 75.0% Outside the ranges
Ratio 1.00 – 1.20 : 1.00 1.21 – 1.25 : 1.00 1.26 – 1.35 : 1.00 Outside the ranges
Girdle Medium Thin to Thick, Facted Very Thin to Very Thick, Facted Outside the ranges

 

Visual Representation