Diamond Education

When people first look at a diamond, what immediately draws them in is its sparkle. And that comes down to one thing: the diamond cut.

Of the Four Cs of diamond cut, color, clarity, and carat, diamond cut is the most important because it gives the diamond life, maximizes sparkle and brilliance. Even a large, high-color diamond will appear dull or lifeless if the cut quality is poor.

Because of this, cut is not only the key to a diamond's visual appeal, it's also one of the most important factors driving its value and price.

This guide will provide you with comprehensive knowledge of what makes an exceptionally cut diamond and why this factor deserves your primary consideration.

What Is Diamond Cut?

Contrary to popular belief, diamond cut doesn't refer to the gem's shape (the external outline of a diamond, like round, pear, cushion, etc). It refers to how well a diamond's facets are shaped and arranged to interact with light to create sparkle and brilliance.

How Are Diamonds Cut?

Unlike carat, color, or clarity—which are determined by nature—a diamond's cut is the result of human artistry. Cutting a diamond is a meticulous process that requires expert knowledge, skilled craftsmanship, and exacting precision.

Rough diamonds are opaque and have little or no sparkle. Expert artisans first assess the rough stone to determine the optimal shape and proportions. Then using specialized tools they carefully cut and polish each diamond, shaping its facets with precision, so it reflects light brilliantly.

When light enters a well-cut diamond, it reflects internally and returns to your eye as white light (brilliance) and colorful flashes (fire). In a poorly cut diamond, light escapes through the bottom or sides, leaving you with a dull or lifeless stone.

Diamond Cut Grade Guide

Once cut, diamonds are graded based on three key quality factors: appearance (brilliance, fire, scintillation), design (proportions), and craftsmanship (polish and symmetry).

GIA's Five-Point Scale

GIA is one of the most respected and widely recognized gemological laboratories in the world. Its grading standards are considered the industry benchmark for evaluating diamonds. The grades are:

• Excellent: This is the highest grade. Diamonds with an excellent cut grade are masterfully crafted and precisely cut to create maximum sparkle and brilliance. Little or no light leakage occurs as light passes through.
• Very Good: Cuts of this grade capture almost all of a diamond's potential. These stones are very brilliant with minimal light leakage. To most viewers, the difference between a Very Good and an Excellent cut is nearly indistinguishable. If you're on a budget, you might choose a Very Good cut so you can prioritize color, clarity, or carat.
• Good: Diamonds of this grade capture light well and possess high degrees of sparkle. Good cut diamonds have some light leakage but still shine bright. Cutters may intentionally cut to Good proportions to achieve a particular look or style. Ideal for budget-conscious buyers seeking a decent-looking stone without the premium price tag.
• Fair and Poor: Diamonds with significant light leakage earn a Fair or Poor grade. These diamonds tend to leak noticeable amounts of light from being too deep or shallow, and they have little brilliance.

NOTE: With Clarity does not sell diamonds of "Fair" and "Poor" cut grades as they don't align with our standards of high-quality jewelry. We also offer Clarity Plus™ Diamonds, a curated selection of stones chosen for exceptional cut precision, optical symmetry, and superior light performance—exceeding traditional grading standards for brilliance, fire, and scintillation.

A Note About IGI Standards

The International Gemological Institute (IGI) is another popular and reputable gemological laboratory you might encounter when purchasing a diamond. If you see an IGI graded diamond, it's important to know that they introduced "Ideal" as their top grade, with "Excellent-Ideal" being the absolute pinnacle for round brilliants. Nevertheless, their standards align closely with GIA's approach.

Diamond Cut Quality Factors: The Science Behind The Sparkle

Understanding the key elements of what makes a diamond cut great helps explain why some diamonds are graded "excellent" whereas some are "good". Experts evaluate cut based on three main factors:

Craftsmanship

• Polish: Refers to the smoothness of a diamond's facets, which affects how well light passes through and reflects back. High-quality polish creates clean, mirror-like surfaces that enhance brilliance, while poor polish can scatter light and diminish sparkle.
• Symmetry: How evenly the facets align with each other and the diamond's overall shape. Perfect symmetry maximizes light reflection and creates the most appealing visual patterns. Meanwhile, poor symmetry creates uneven light return and reduces sparkle.

Appearance

• Fire: Rainbow colors that flash from a diamond as it moves. It's a result of spectral separation or dispersion of white light into primary colors.
• Brilliance: The total white light (both internal and external reflections) returned to the eye.
• Scintillation: The interplay between bright and dark areas within the diamond seen as it moves. This is what creates its mesmerizing "sparkle".

Design

• Proportions: Refers to the relationship between a diamond's angles, facet sizes, and overall dimensions. Well-proportioned diamonds reflect light perfectly, while uneven proportions can cause light to escape, reducing sparkle.

Cut quality comes down to precision, skill, and control – and even the smallest variations can change how a diamond handles light. That's why master cutters spend years refining their craft, ensuring every angle, facet, and polish is executed to perfection.

Diamond Anatomy 101: Know Your Stone

To understand how a diamond's cut is evaluated, it's essential to understand the key structural components of a diamond. Each part influences how light enters, reflects, and exits your stone. When all these characteristics are well balanced, your diamond will deliver exceptional brilliance and sparkle.

• Table: The largest and top-most facet (flat part) of your gem—this is where light enters your diamond.
• Crown: The upper portion of a diamond that starts from the girdle and goes all the way to the table. The crown is crucial for light performance.
• Girdle: The thin perimeter that separates the crown from the pavilion. It provides structural integrity and acts as a reference point for setting.
• Pavilion: The lower portion of a diamond that starts from the girdle and goes all the way to the culet. Get the angles wrong here, and light escapes your diamond instead of bouncing back.
• Culet: The very bottom point or tiny facet. In well-cut diamonds, this should be nearly invisible to the naked eye.
• Depth: This measures the height of your diamond from a diamond's table (top surface) to its culet (bottom point), influencing how well light is reflected within the diamond.

Why Cut Beats Everything Else (Yes, Even Carat Weight)

Among the 4Cs, cut has the greatest influence on a diamond's overall beauty. Here's why it deserves to be your top priority:

• Appearance: Cut dictates how effectively a diamond reflects light, impacting its beauty and brilliance. The better the cut, the more your diamond will sparkle.
• Perceived size: A well-cut diamond with ideal proportions can appear bigger than a poorly cut stone of the same carat weight because light is optimally reflected, making the stone appear fuller and more vibrant.

Gemologists recommend prioritizing cut over all other factors, even diamond size, because it has the greatest impact on brilliance and beauty. Whether you're intending to get a natural or lab-grown diamond for your engagement ring or jewelry, it's always best to select the highest cut grade you can afford.

The Price Reality: How Does Diamond Cut Quality Impact Cost?

The higher the cut quality, the higher the diamond's price. Here's how it significantly affects your wallet:

• Ideal / Excellent grades: Ideal grades are the most expensive, followed by excellent grades as they maximize light performance and sparkle. Expect to pay 15–25% more than what you would for Very Good, but the visual payoff is worth it.
• Very Good cuts: Offer excellent light performance at a slightly lower price point. While they don't achieve the same level of precision and sparkle as Ideal or Excellent cuts, they still reflect most light beautifully and often appear nearly indistinguishable to the untrained eye. This grade is a popular budget-friendly choice for buyers who want to prioritize carat size or higher color and clarity grades without sacrificing too much on sparkle.
• Good cuts: Good cut diamonds are proportioned well enough to reflect a fair amount of light, but their brilliance is noticeably lower than higher grades when viewed side by side. They're more affordable, allowing buyers to allocate more of their budget toward size or other quality factors.
• Fair and Poor cuts: Diamonds in these categories generally have significant proportion and symmetry issues, causing light to escape rather than reflect back to the viewer. As a result, they often look dull or flat, even if they score well in color or clarity. We don't recommend purchasing these.

The jump from a Very Good stone to an Excellent one can make a meaningful difference in a diamond's brilliance and fire, making the investment worthwhile.

Types of Diamond Cuts

Diamonds are typically cut in two ways: step cuts and brilliant cuts.

Brilliant Cut

Diamonds are faceted to maximize the fire and scintillation. They possess more facets than step cut diamonds and the facets are triangular and kite-shaped. Round cut diamonds and Princess cut diamonds are typically cut in this fashion.

Step Cut

Step cut diamonds, such as Emerald cut diamonds and Asscher cut diamonds, have angular facets that highlight the diamond's scintillation. These cuts are elegant but because they have fewer facets do not reflect light as much as brilliant cut diamonds.

Both types of diamond cuts have unique beauty. It's important to consider which type of diamond sparkle you want while picking a diamond cut.

Finding Your Perfect Cut

If you're looking for your perfect diamond cut for an engagement ring or other diamond jewelry, consider these factors to get the best value:

• If you want maximum sparkle: Prioritize Excellent cut and adjust other factors like carat weight.
• If you want great sparkle while not breaking the bank: Cuts with a grade of 'Very Good' can offer 90% of the performance of higher cuts but at better prices.
• If budget is top priority: Consider a 'Good' grade, or potentially a 'Very Good' but in a fancy shape, as they typically cost 20–30% less than round brilliants.

Pro Shopping Tips

• See before you buy: If you're shopping in person, examine diamonds under different lighting conditions – fluorescent, LED, and natural light all reveal different aspects.
• Always choose certified diamonds: It doesn't matter whether you're choosing natural diamonds or lab-grown gems; we recommend you choose only certified diamonds to ensure you're getting exactly what you pay for. Reputable certifications from organizations like GIA or IGI provide an unbiased assessment of quality and authenticity, protecting you from misrepresentation and helping maintain the stone's long-term value.
• Don't chase absolute perfection: The difference between Excellent and Very Good cut grades is often nearly impossible to spot with the naked eye. In everyday wear, both will sparkle beautifully, so it often comes down to personal preference and budget.

A Cut Above the Rest

Now you know how to shop for a diamond that sparkles as much as your priorities and budget allow. By understanding how cut affects beauty, value, and performance, you can choose a stone that truly dazzles – whether it's a timeless round brilliant or a unique fancy shape. Remember, it's always better to go a little smaller in carat size but with exceptional cut than opt for a bigger diamond with a lower grade cut.

Diamond Cut FAQs

What's the real difference between diamond cut and diamond shape?

Shape is the outline you see from above (round, oval, princess), while cut refers to how well the diamond has been faceted and polished within that shape.

Is spending extra for an Excellent cut actually worth it?

Spending extra for an Excellent cut gives you maximum sparkle and brilliance, visible under close inspection. But in everyday wear, a Very Good cut often looks just as stunning, making it a smart budget-friendly choice.

Can I really see the difference between Excellent and Very Good?

Side-by-side, most people can spot the difference. In isolation, Very Good cuts still look stunning. But if your budget is tight, Very Good offers excellent value without major visual compromise.

Which diamond cut gives me the most sparkle for my money?

Round brilliant cuts are scientifically optimized for maximum light return. If sparkle is of top priority, stick with rounds in Excellent or Very Good grades.

Do lab-grown diamonds get the same cut grades?

Absolutely. Lab-grown diamonds are graded using the same cut standards as natural diamonds. Organizations like GIA and IGI evaluate lab-grown stones for cut, color, clarity, and carat weight just like natural diamonds.