Emerald Cut Diamonds | In-Depth Guide, Ideal Proportions & L/W Ratios

Sharif Khan
Sharif Khan
Last Updated    EST 
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The cutting of diamonds into an emerald shape dates back to the 13th and 14th centuries when diamonds started gaining popularity in culture. The modern emerald cut diamond has 49 facets or more, with roughly 25 on the crown, 25 on the pavilion, and eight on the girdle, forming three rows of bottom and top steps. These brilliant gems feature a step-cut (or trap-cut) with facets arranged in a rectilinear style parallel to the girdle, creating a staircase-like appearance, hence the name step-cut.

During the Art Deco period, many antique jewelry pieces showcased step-cut styles, which is why diamond enthusiasts today are eager to recapture the aesthetics of that time. If you love classic styles commonly found in antique jewelry, an emerald cut diamond is the perfect choice.

Typically, the corners of diamonds are the weakest points for a regular stone, but emerald cut diamonds beautifully address this concern. The emerald cut diamond also features a keel running through the pavilion terminus, a unique characteristic not found in other diamond cuts.

This guide offers comprehensive insights into cut proportions, clarity, color, fluorescence, and certification-related insights into emerald cut diamonds.

Keep Points to Know

  • Buy an emerald cut diamond with a depth of 61-67%, table 62-70%, and a length-to-width ratio of 1.4-1.5.
  • Avoid fluorescence in colorless diamonds, and make sure the stone comes with a GIA grading report.

While prioritizing the 4Cs, consider an emerald cut diamond like this: example 1, VVS/D-E range for a pure investment-grade diamond in the highest quality range. Consider an emerald cut like this: example 2, VS-F/G range to maximize quality without compromising carat weight. If you do not mind compromising quality slightly to maximize the carat weight, consider an option like this: example 3, VS-SI1/I-J range. Finally, buyers can compromise on color entirely under the fourth scenario to maximize cut, clarity, and carat weight and get a big diamond such as this option: example 4, VVS/VS-K-M range.

emerald cut diamond depth and table

Search & Watch Emerald Diamonds in HD 360 Degrees.

Emerald Cut Key Insights

Before buying emerald cut diamonds, here are the key factors to consider with regard to cut proportions, color, clarity, certification, fluorescence, and settings.

Shape Popularity
Emerald cut diamonds are among the most popular diamond shapes. They are different because of their classic and antique shape and have a step-cut with only as few as 49 facets. If you want elegance, go for an emerald cut diamond. In addition to square emerald cuts, a good square alternative to the emerald cut diamonds is the Asscher cut.
A depth of 59–69% and a table of 58–72% are recommended. See the chart below for precise instructions.
L/W Ratio 
While a length-to-width ratio of 1.3-1.55 is standard, we generally prefer the 1.4-1.5 range. See more below.
D-F are colorless ranges, G offers great value, and H/I are exceptional budget options. See our chart below for comparison.
Since emerald cut diamonds have open facets, prioritize their clarity with VS2/SI1 as the minimum acceptable grade. See more below.
We recommend AGS and GIA as the top grading labs for diamonds. Review the section below on how to read a grading report carefully. 
From our experience, halo settings with round melees complement emerald cut diamonds beautifully. For reference, check our list of the top ten emerald cut engagement rings.
Best Places to Buy
Here is our list of the best places to buy diamonds. Additionally, lab-grown diamonds are a good option for buyers with a tight budget.

Emerald Cut Ideal Proportions

The chart provided below serves as a general guideline for evaluating the cut of an emerald cut diamond. Traditionally, a length-to-width ratio of 1.50 is considered the classic for a rectangular-shaped emerald cut diamond. However, in recent times, there has been a trend towards a more square shape, with a length-to-width ratio of 1.30.

emerald cut diamonds

Using James Allen's 3D Video Technology and comparing emerald cut diamonds with their 360-degree videos can be immensely helpful in determining how the following proportions and different length-to-width ratios affect the visual appearance of a diamond. Compare several options with their search filter to get a good sense of what to prioritize in terms of cut.

Refer to the chart below for precise proportions and the specific length-to-width ratio of these elegant diamonds. 

Depth %

Poor/Fair: <52.5 or > 80 / 74.6 - 80

Good: 57 - 59 / 71- 74.5

Very Good: 58-61/67.4-70.1

Excellent: 61.3 - 67

Table %

Poor/Fair: <50 or >80/50-52.5 or 75.5-80

Good: 53-57/74

Very Good: 58-61/71

Excellent: 62-70


Poor/Fair: Very Large/Large

Good: Slightly large

Very Good: Medium/Very Small

Excellent: None


Poor/Fair: Ex. Thin – Ex. Thick

Good: Very thin - thick

Very Good: Very thin - slightly thick

 Excellent: Very thin - slightly thick

Square L/W Ratio

Poor/Fair: >1.09 /1.07-1.09

Good: 1.05-1.06

Very Good: 1.00-1.04

Excellent: 1.00-1.04

Rectangular L/W Ratio 

Poor/Fair: >1.90 /1.81-1.90

Good: 1.20-1.29/1.63-1.80

Very Good: 1.30-1.38/1.51-1.70

Excellent: 1.39-1.50

Emerald Cut Diamond Shape Pattern

Picking the Best Color for Emerald Cut Diamonds

Like evaluating the color in other diamond shapes, the color in an emerald cut diamond is critical. The higher the color grade, the better. In our experience, many buyers prefer stones with warm colors over colorless ones, given the price difference.

Warmer colors refer to the near colorless range of G-I color diamonds in the color spectrum, while the colorless ones refer to D-F color diamonds. The price premium for a warmer color grade emerald cut diamond is be significantly lower. However, since the body of emerald cut diamonds is large and contains open facets, choosing a higher color grade is recommended.

Diamond Color Chart

For more detailed information selecting the best color for an emerald cut diamond, use the chart below based on carat weight while buying one:

< 0.50 Carat

Poor/Far: >M/ L-M

Good: I

Very Good: G-H

Excellent: D-G

0.51 – 1.0 Carat

Poor/Fair: J-K / >L

Good: I

Very Good: H

Excellent: D-G

1.0 – 2.0 Carat

Poor/Fair: H-I / >I

Good: J/I

Very Good: G-H

Excellent: D-F

>2.0 Carat

Poor/Fair: H-I / >I

Good: H-I

Very Good: F-G

Excellent: D-E


Poor/Fair: Very Strong/Strong

Good: Medium 

Very Good: Faint

Excellent: None

Selecting the Best Clarity for Emerald Cut Diamonds

Since emerald cut diamonds have open facets, we recommend buying a slightly higher clarity stone. However, each of our customers has a unique standard for clarity and color. Some want flawless diamonds, while others are perfectly comfortable with inclusions if they are not noticeable to the naked eye.

GIA's clarity grading system is highly helpful in selecting the best clarity grade that will meet a buyer's particular requirements.

Diamond Clarity Chart

On the clarity scale, the VS2 range would be an outstanding balance of price and appearance in an emerald cut diamond. Review the chart below carefully for our recommended clarity grade for an emerald cut diamond based on its carat weight:  

< 0.50 Carat

Poor/Far: >I1/ I1

Good: SI1-SI2

Very Good: SI1-SI2

Excellent: FL-VS1

0.51 – 1.0 Carat

Poor/Fair: I1-I3

Good: SI1-SI2

Very Good: VS2-SI1

Excellent: FL-VS1

1.0 – 2.0 Carat

Poor/Fair: I1 / >I1

Good: SI2

Very Good: SI1/ VS2

Excellent: FL-VS1

>2.0 Carat

Poor/Fair: I3/II1

Good: SI2

Very Good: SI1/VS2

Excellent: FL-VS1

Evaluating Emerald Cut Diamond Grading Reports

In addition to the well-known 4Cs, it is imperative for buyers to be familiar with the following key aspects of an emerald cut diamond grading report or certificate, as highlighted in the image below.

emerald cut grading report

Watch HD Video of this Diamond.

Measurements: This is significant as it provides the buyer with information about the surface size of the diamond, indicating how large the diamond will appear in millimeters. Additionally, it will offer you the length-to-width ratio by dividing the length by the width (in the above case, it is 8.07 / 5.88 = 1.38).

Fluorescence: This should be regarded as the fifth C. Considering that the color is G, avoiding fluorescence is the optimal choice in this specific example. However, medium blue fluorescence is not as concerning as strong blue fluorescence.

Proportions: This chart is the most crucial for assessing the cut of a diamond. Specifically, pay attention to the table percentage (62.6% in the example - excellent), depth percentage (67% - excellent), girdle (medium - excellent), and culet (none - excellent).

Clarity Characteristics: This section will indicate the types of inclusions and their respective locations. It can help buyers avoid diamonds with visible inclusions at the center. These details are also useful for correlating the report with the diamond, as these inclusions serve as the diamond's unique birthmarks.

Inscriptions/Comments: This section will present factors related to clarity and will also indicate whether a diamond has undergone clarity enhancement, using methods like laser drilling or color enhancement, among others. Additionally, pay attention to comments such as "clarity grade based on clouds," which is a concerning indicator within clarity grades of VS2 and below. The laser inscription of the report number on the girdle is positioned above the comments section, offering an optional service for added verification.

Considering Budget Options

The following options regarding carat weight, cut, color, and clarity are suggested for people with budget constraints.

emerald diamond engagement ring

Emerald Shaped Halo Engagement Ring Custom Designed by Petra Gems

Excellent Choice

  • At Least 1.2 Carats in Weight
  • Very Good to Excellent Polish and Symmetry
  • G or above in Color
  • SI1 or above in Clarity
  • No Fluorescence
  • Length/width ratios: 0.95 - 1.05 for a square or 1.5 to 1.60 for a rectangular shape

Very Good Choice

  • At Least 1.00 Carat in Weight
  • Good to Excellent Polish and Symmetry
  • H or above in Color
  • SI1 or above in Clarity
  • None, faint or medium blue Fluorescence
  • Length/width ratios: 0.95-1.05 for a square or 1.45 to 1.65 for a rectangular shape

Good Choice

  • At least 0.90 Carats in Weight
  • Good to Very Good Polish and Symmetry
  • I or above in Color
  • SI1 or above in Clarity
  • None, faint or medium blue Fluorescence
  • Length/width ratios: 0.95-1.05 for a square or 1.4-to 1.68 for a rectangular shape