Diamond Cut vs. Shape – The Facts You Need to Know

Feb 24 2025 Lior Elgrissy 0 comments

Diamond Cut and Diamond Shape

When buying a diamond you may hear the terms diamond cut and diamond shape used interchangeably. But they are two very different things. Understanding the difference is key to making an informed decision when buying an engagement ring or fine jewelry.

A diamond’s shape determines its outside appearance, while the cut quality determines its brilliance and sparkle. Knowing how these affect a diamond’s beauty and value will help you choose the right diamond for you.

What Is Diamond Shape?

The shape of a diamond is its physical form and outline. Diamonds come in many shapes, each with its own style. The choice of shape is mainly down to personal preference and style.

Diamond Shapes:

Round: The classic and most popular diamond shape, maximum brilliance.
Princess: A modern square shape with sharp edges, high brilliance.
Cushion: A square or rectangular shape with rounded corners, a pillow.
Oval: An elongated round diamond, looks bigger.
Emerald: A rectangular shape with step-cut facets, clarity over brilliance.
Pear: A teardrop shape, round and marquise combined.
Marquise: A long, pointed oval shape, makes the diamond look bigger.
Heart: A romantic heart shape, often chosen for sentimental value.

Choose a shape that suits you and your lifestyle. Some shapes like round or princess are more durable, others like marquise or pear require more care due to their pointed edges.

What Is Diamond Cut?

Diamond cut refers to the precision of the diamond’s facets, angles and proportions which directly affect its ability to reflect light. A well cut diamond maximizes brilliance, fire and scintillation.

How Cut Affects Sparkle:

Brilliance: The white light reflection that makes a diamond look bright.
Fire: The dispersion of light into different colours, a rainbow effect.
Scintillation: The sparkle effect caused by light moving across the diamond’s surface.A diamond’s cut is graded by certification bodies like GIA (Gemological Institute of America) on the following scale:

Excellent: Maximum sparkle and light performance.
Very Good: High sparkle with slight light variation.
Good: Moderate sparkle, good for budget conscious buyers.
Fair: Less sparkle due to proportions allowing light to escape.
Poor: Lacks sparkle, significant light leakage.

Why Choose the Right Cut

A poorly cut diamond, regardless of shape or carat weight will not sparkle as much as a well cut stone. Even a flawless diamond with perfect clarity and color can look dull if the cut is not right. That’s why cut quality is often considered the most important factor when evaluating a diamond’s beauty.

If you want the best cut diamond a round brilliant cut with an "Excellent" or "Very Good" grade will give you the most sparkle and light return.

Diamond Cut vs Diamond Shape

To clarify the difference between these two terms here’s a simple summary:

Diamond Shape:

Refers to the outside appearance of the diamond.
Examples: Round, Princess, Cushion, Oval, Pear etc.
Based on personal style and preference.

Diamond Cut:

Refers to the quality of the diamond’s proportions and facets.
Affects sparkle, fire and brilliance.
Graded by certification bodies (GIA, AGS etc.).

How to Choose the Right Diamond for You

When buying a diamond you need to consider both the shape and cut quality. Follow these steps to choose the best:

Choose a Shape: Select a shape that fits your style and preference.
Prioritize Cut Quality: Go for an "Excellent" or "Very Good" cut grade for maximum sparkle.
Consider Carat Weight: Balance size and cut quality within your budget.
Check Certification: Ensure the diamond is certified by a reputable lab like GIA or AGS.
Set a Budget: Allocate more for a well cut diamond as it enhances the overall appearance.It’s key to understand the difference between diamond cut and diamond shape when buying a diamond. While shape is the outside appearance, cut quality is the sparkle. Always choose a well cut over size or shape alone, as cut quality is what makes a diamond beautiful and valuable.