ANATOMY OF A MARQUISE DIAMOND
About The Marquise Cut
The name is derived from the Marquise of Pompadour, for whom King Louis XIV of France allegedly had a stone fashioned to resemble what he considered her perfectly shaped mouth.
The marquise diamond tends to create the appearance of a larger carat size compared to round and princess cut diamonds of similar weight, due to it's length and narrowness. This unique shape also tends to make the hand of it's wearer appear longer and slimmer.
Key Anatomy Of A Marquise Diamond
Preferred Proportions
There is no official perfect "length to width" ratio of the marquise diamond - personal preference and diamond availability are likely to dictate the choice of diamond.
However, the classic marquise length to width ratio is considered to be between 1.75 and 2.15.
Symmetry & Setting
Symmetry is very important in marquise diamonds. The two end points should closely align with each other. Any material misalignment in the points can result in an off kilter look in the final setting. For this reason it is advisable to opt for a marquise diamond with at least very good symmetry or better.
A marquise diamond should always be set with prongs to protect the two points to mitigate against chipping. Because these points were once nearest the outer edge of the original uncut rough stone, flaws such as extra facets and other inclusions may be positioned here.
With both points covered by prongs these flaws will be invisible once the diamond is set.
Shape According To Length/Width Ratios
Source: GIA Education
Table %
Excellent 53 - 63
Very Good/Fair 50 - 52 or 64 - 70
Poor < 50 or > 70
Depth %
Excellent 58 - 62
Very Good/Fair 50 - 57.9 or 62.1 - 74
Poor < 50 or > 74
L/W Ratio
Excellent 1.85 - 2.10
Very Good/Fair 1.55 - 1.84 or 2.11 - 2.45
Poor < 1.55 or > 2.45
Culet
Excellent None to Very Small
Very Good/Fair Small to Medium
Poor > Medium
Colour & Clarity
Discerning the colour in a marquise cut diamond is subjective. Most of the price premium associated with a marquise diamond at the top end of the colour scale is dictated by supply and demand, with customers seeking D/E/F colour grades willing to pay a premium to get them.
The actual differences in colour are difficult to perceive in moderate carat sizes such that a hefty premium is not generally warranted.
We suggest a colour grade of G/H below one carat weight and F/G above.
Fluorescence should be non existent or faint.
Classically Proportioned Marquise Diamond 2:1
Like colour, the importance of clarity is a subjective measure and is of greater importance to one person than another. Tiny inclusions within a smaller carat weight diamond will be almost invisible to the naked eye, especially if the chosen diamond is considered 'eye clean'.
We therefore suggest a clarity grade in the range of VS1/VS2/Si1/Si2 for marquise diamonds around one carat or less. Much above this carat weight we recommend clarity in a range of VVS2/VS1/VS2/Si1.