Understanding the 4 C’s of Diamonds

At Heller Jewelers, we believe choosing the perfect diamond should be a memorable and informed experience. Whether you’re planning a proposal or selecting a meaningful gift, understanding the 4 C’s of diamonds—Cut, Color, Clarity, and Carat—can help you find the stone that perfectly fits your vision and budget.

Cut refers not to the diamond’s shape (like round, princess, or oval), but to how well it has been cut and faceted. This determines how light reflects off the diamond, which directly impacts its brilliance and sparkle.

• Excellent or Ideal Cut: Maximizes the diamond’s brightness and fire.

• Good Cut: Reflects most light well but may sacrifice a bit of brilliance.

• Poor Cut: Dull appearance due to inadequate light reflection.

The color of a diamond actually refers to its lack of color. Graded on a scale from D (colorless) to Z (light yellow or brown), the less color a diamond has, the higher its grade and value.

• D-F: Colorless (exceptionally rare)

• G-J: Near colorless (excellent value)

• K-Z: Noticeable color

Clarity refers to the presence of inclusions (internal flaws) or blemishes (external marks). Diamonds are graded on a clarity scale from Flawless (FL) to Included (I1, I2, I3).

• FL – IF: Flawless to Internally Flawless

• VVS1 – VVS2: Very, Very Slightly Included

• VS1 – VS2: Very Slightly Included

• SI1 – SI2: Slightly Included

• I1 – I3: Included (visible to the naked eye)

Carat measures the weight of a diamond, not its physical size. One carat equals 200 milligrams. All else equal, the higher the carat weight, the more valuable the diamond—though cut and proportions also affect visual size.

At Heller Jewelers, we’re committed to helping you navigate the diamond-buying journey with confidence. Whether you're choosing an engagement ring or a timeless piece for yourself, our expert team is here to guide you through every sparkle and facet.

Visit our San Ramon showroom or browse our curated diamond selection online. Let us help you find a diamond that tells your story—with brilliance, beauty, and meaning.