The 4 Cs of Diamonds: What to Know Before Buying an Engagement Ring

At Jahan Diamond Imports, we understand that choosing an engagement ring is one of life’s most meaningful decisions. Every diamond tells a story — and knowing how to choose yours starts with understanding the Four Cs: Carat, Cut, Color, and Clarity.

This simple yet essential framework helps you discover a diamond that reflects not just brilliance, but your love story.

Carat – The Diamond’s Weight

Carat refers to the weight of a diamond — a detail many shoppers focus on first. While carat often influences size and price, it’s just one piece of the puzzle. One carat equals 200 milligrams. While it’s easy to think of carat as a direct indicator of size, it's important to note that two diamonds of the same carat weight can look very different depending on their cut and shape.

A beautifully cut diamond of a slightly lower carat weight can often appear just as stunning as a larger one — sometimes even more so.

Jahan Tip: Look just below key milestones (like 0.90 ct instead of 1.00 ct) for exceptional value without sacrificing visual impact.

Cut – The Sparkle Factor

Cut is arguably the most important of the Four Cs. It doesn’t refer to the shape (like round, oval, or emerald), but rather how well the diamond has been cut and proportioned to reflect light. A diamond with an excellent cut radiates with brilliance and fire, no matter the carat weight.

A diamond with an excellent cut will sparkle brilliantly, while a poorly cut diamond — even if it's high in carat, color, and clarity — may look dull or lifeless. At Jahan, we believe cut is very important, and we hand-select diamonds that reflect light beautifully from every angle.

Jahan Tip: If you want a diamond that truly shines, go for Excellent or Very Good cut grades.

Color – The Diamond’s Hue

Diamonds come in a range of natural tones, graded from D (colorless) to Z (light yellow). Most of what we carry at Jahan falls within the colorless to near-colorless range (D–H).  The closer a diamond is to D, the more “colorless” it is — and the more expensive it tends to be.

That said, many diamonds in the G–J range appear nearly colorless to the naked eye, especially once set in a ring. Still, the best color for you depends on the ring’s setting and your personal preference. Warmer tones can look stunning in yellow or rose gold.

Jahan Tip: Don’t overpay for perfection — sometimes a near-colorless diamond offers a more balanced beauty for your setting and budget.

Clarity – Natural Characteristics

Clarity speaks to the natural inclusions formed within a diamond over millions of years. These tiny characteristics make every stone one of a kind. The GIA clarity scale runs from Flawless (FL) to Included (I1–I3). While flawless diamonds are extremely rare, many inclusions are so small they can’t be seen without magnification.

Most diamonds appear perfectly clean to the naked eye, even if they aren’t technically “flawless.” At Jahan, we carefully inspect each stone to ensure it meets our high standards for visual purity and sparkle.

Jahan Tip: Focus on how the diamond looks to you, not just under a microscope. Eye-clean diamonds offer incredible beauty and lasting value.

Your Story, Set in Stone

The Four Cs work together to help you find a diamond that speaks to your style, values, and vision. At Jahan Diamond Imports, we’ve guided generations of couples through this process with unmatched expertise and a personal touch.

Whether you’re celebrating a timeless romance or just beginning your journey, we’re honored to help you find the perfect diamond for your engagement ring.

Make an Appointment

Explore our curated collection or begin the journey toward a one-of-a-kind custom engagement ring.

We welcome you to schedule a private appointment at our San Francisco showroom at your convenience.

Contact us or call us at (415) 956-6391.