The 4 C's
The 4 C’s of Gemstones: Cut, Color, Clarity & Carat
Understanding What Makes a Gemstone Truly Valuable
When buying a gemstone, you’ll often hear about "The 4 C’s"—Cut, Color, Clarity, and Carat. These four factors determine the beauty, brilliance, and value of a gemstone. Whether you're shopping for diamonds, moissanite, sapphires, rubies, or emeralds, understanding the 4 C’s will help you make a more informed purchase.
1. Cut – The Sparkle Factor
Cut is the most important factor in how a gemstone sparkles. A well-cut stone reflects light beautifully, while a poorly cut one may appear dull.
Types of Cuts:
- Ideal / Excellent Cut – Maximum brilliance, best light performance
- Very Good Cut – Slightly less sparkle but still high quality
- Good Cut – Less light return, more affordable
- Fair / Poor Cut – Duller appearance, often too deep or too shallow
Key Takeaway: A well-cut stone outshines a bigger stone with a poor cut. Prioritize cut for maximum brilliance.
2. Color – From Colorless to Vibrant Hues
Color grading applies mostly to diamonds but is also important for colored gemstones.
Diamond Color Grading (D-Z Scale):
- D-F: Colorless (most valuable, pure white appearance)
- G-J: Near-colorless (good balance of value and whiteness)
- K-M: Faint yellow (slightly warm tone)
- N-Z: Noticeable yellow tint (less expensive)
For colored gemstones, richer and more intense colors tend to be more valuable.
Key Takeaway: If choosing a diamond, D-F offers the purest white, but G-J is a great balance of price and beauty.
3. Clarity – Flaws vs. Flawless
Clarity refers to the inclusions (internal flaws) and blemishes (surface flaws) within a gemstone.
Clarity Grading Scale (Diamonds & Moissanite)
- FL-IF (Flawless / Internally Flawless) – No visible inclusions, rarest & most expensive
- VVS1-VVS2 (Very, Very Slightly Included) – Nearly flawless, microscopic inclusions
- VS1-VS2 (Very Slightly Included) – Small inclusions, not visible to the naked eye
- SI1-SI2 (Slightly Included) – Visible inclusions under magnification, some visible to the naked eye
- I1-I3 (Included) – Noticeable inclusions, may affect durability
For colored gemstones, clarity grading varies by type. Some gems, like emeralds, naturally have inclusions and are valued differently.
Key Takeaway: VS or higher is ideal for eye-clean diamonds. For colored stones, prioritize color over clarity.
4. Carat – Size & Weight
Carat weight measures the mass of a gemstone, but size perception varies by cut and shape.
Check out our size guide for more information about carat weight and sizes for various gemstone shapes.
Key Takeaway: Carat doesn't equal size–a well-cut smaller stone can look bigger than a deep-cut larger stone.
How to Choose the Right Gemstone
Now that you understand the 4 C’s, here are a few quick tips:
- For Maximum Sparkle: Choose the best cut you can afford.
- For Best Value: Consider near-colorless diamonds (G-H) instead of D-F.
- For Eye-Clean Stones: VS1-VS2 or SI1 clarity offers a great balance.
- For Size Impact: Fancy shapes (ovals, emeralds) appear larger than round stones.
Shop High-Quality Gemstones
Now that you know how to choose the perfect gemstone, explore our hand-selected collection of diamonds, moissanite, sapphires, rubies, emeralds, and more.