Princess Cut Diamonds Assessment Chart Guide In-depth Information

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Evaluating Princess Cut Diamonds:

This fancy “French” inspired cut diamond was made popular by Betzalel Amber and Israel Itzkowitz in the 1970s. Princess cut diamond is our most popular non-round diamond because of its brilliance and unique cut which makes it a favorite diamond for unique engagement rings.

Princess cut diamonds have pointed corners and are traditionally square cut. We use the term “traditionally” because many princess cut diamonds are slightly rectangular. The price of the diamond is slightly affected by how precisely the diamond is cut into a square despite the fact that many consumers prefer a rectangular cut; often it’s all about what you prefer in a diamond. As shown in the picture below, rectangular princess cut diamonds have a distinct advantage over square princess cut diamonds - they look larger (both of the following princess cut diamonds are one carat in weight). If you have slim fingers, a rectangular princess cut diamond might be the choice for you.  

square vs rectangular princess cut diamond

Be sure to check out our diamond filter to compare actual prices. 

Key factors to take into consideration while buying a princess cut diamond include the color, clarity and cut.

Analyzing Cut:

Princess cut diamonds don’t have an assigned cut grade in GIA's grading reports. However, AGS does assign a cut grade to princess cut diamonds. There isn’t a constant agreement as to what proportions the princess cut should be. This is a conundrum for many suppliers and consumers of princess cut diamonds.

If you would like our view on it, we think you should look for a diamond whose total depth is about 70% (with a tolerance of 5%). Another rule of thumb would be to check for the diamond’s polish and symmetry grade to be at least Good.

Generally, the diamond’s brilliance is maximized by how nicely it has been cut without making the diamond look too deep or too shallow. Please follow the chart guide below for determining the cut of a princess cut diamond:

Depth %

Excellent: 64-74.9

Very Good: 64-74.9

Good: 59-64/75.5-81

Fair: 56.5-84

Poor: <54 or >84

Table %

Excellent: 62-69

Very Good: 58-61/71.1-73.9

Good: 55-59/75-81

Fair: 55-81/52-85.3

Poor: <52 or >87

Crown Height %

Excellent: 10-16

Very Good: 9-15.5

Good: 6-17.9/8-17

Fair: 5.2-18/4.1-20

Poor: <3.2 or >21

Girdle

Excellent: Very Thin-Slightly Thick/Thin-Thick

Very Good: Very Thin-Slightly Thick/Thin-Thick

Good: Very Thin-Thick

Fair: Very Thin-Very Thick

Poor: Extremely Thin-Extremely Thick

Length/Width Ratio: Square Range

Excellent: 1.00-1.05

Very Good: 1.00-1.05

Good: 1.00-1.05

Fair: 1.059-1.079

Poor: >1.079

Length/Width Ratio: Square Range

Excellent: 1.00-1.05

Very Good: 1.00-1.05

Good: 1.00-1.05

Fair: 1.059-1.079

Poor: >1.079

Cullet

Excellent: None

Very Good: Slight

Good: Small

Fair: Average

Poor: >Average

Length/Width Ratio: Square Range

Excellent: 1.00-1.05

Very Good: 1.00-1.05

Good: 1.00-1.05

Fair: 1.059-1.079

Poor: >1.079

Length/Width Ratio: Rectangular Range

Excellent: 1.49 -1.73

Very Good: 1.49 -1.1.73

Good: 1.49 -1.173

Fair: 1.48 -1.74/2.00

Poor: <1.48 - >2.00

The chart above represents a set of guidelines created for you to use as a rule of thumb when evaluating the cut of a princess cut diamond. We would like to advise you to avoid any princess cut diamonds that have smaller depth percentage than table percentage.

Choosing Color:

H Color or I Color in a princess cut diamond will give you more value for your money. Although, the higher the color, the better the diamond is. One thing to look for when evaluating the color of a princess cut diamond is to look for a diamond that don’t have a visible yellow tint. For that reason, you are better off if you don’t choose a color grade lower than G, H and/or I.

It is not important to spend additional money to buy a Colorless princess cut diamond i.e. ones graded as D, E, and/or F. Any of these colorless grades will not have a conspicuous difference in color with the naked eye as say G or H colors. 

Selecting Clarity:

We like princess cut diamonds because of their proportions, unlike other diamond shapes, exhibit significant brilliance and sparkle. This is a valuable aspect of princess cut diamonds because the brilliant proportion makes a diamond’s inclusion less visible.

Although, princess cut diamonds with clarity lower than SI1 are rare, you may still find your dream princess cut diamond if you focus on buying a diamond with VS1, VS2, SI1, and/or SI2 graded clarity.

One thing to pay attention to when buying these sparkling diamonds is to make sure the diamond you choose doesn't have serious inclusions in its corners. Large inclusions lead to weakened corners which then makes the diamond susceptible to chipping.

Selecting a Setting:

Always make sure to choose a setting that protects the diamond’s corners. When a diamond is set in a mounting that has rough edges, it causes the diamond to become very thin. Not just that, a strong blow can also eventually chip the diamond off.

To provide a safe mounting for your diamond, choose a V-prong setting. 

Suggested carat weight, cut, color and clarity of Princess Cut Diamond for people with budget constraints:

Excellent Choice:

  • At least 1.0 carats in Weight
  • Very Good to Excellent Polish and Symmetry
  • G or above in color
  • SI1 or above in clarity
  • No Florescence
  • Length/width ratios: 1-1.05 for square or 1.5-1.75 for rectangular shape

Very Good Choice:

  • At least 0.90 carats in Weight
  • Good to Excellent Polish and Symmetry
  • H or above in Color
  • SI2 or above in Clarity
  • None, faint or medium blue florescence
  • Length/width ratios: 0.95-1.05 for square or 1.5-1.75 for rectangular shape

Good Choice:

  • At least 0.80 Carats in Weight
  • Good to Very Good Polish and Symmetry
  • I or above in Color
  • SI2 or above in Clarity
  • None, faint or medium blue florescence
  • Length/width ratios: 0.95-1.05 for square or 1.5-1.75 for rectangular shape

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